Need help! Shutting off while driving...
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Need help! Shutting off while driving...
I'm almost tearing my hair out now... I've been without a car for a week, and Canadian winters spent waiting for hours at bus stops are killing me
I started having issues with my car (1986 Camaro SC 2.8 MPFI) last summer - it was running beautifully, no problems of any kind... and all of a sudden, the engine just shuts down when accelerating from traffic lights. RPM gauge drops down to 0 and there's no power. As i stopped, I heard the engine still puffing irregularily ("puff... puff... .... kapuff... puff..."). Shut it down, tried to start again - it just cranked and wouldn't fire up.
My mechanic narrowed the problem down to a blown ignition coil, replaced it (also, we installed a new distributor cap, spark plugs and spark plug cables) - and the car ran beautifully for about 4 months, when it crapped out in a very similar way again - just entered the highway, started picking up speed - the engine paused for a moment, picked up again, then shut off for good.
This time the problem was a rusted distributor - we've replaced the whole thing with a brand new one, and "Cammy" ran beautifully again for another 3 months. A bit later I noticed a lack of power, which I later tracked down to a vacuum leak (with the help of this forum ). Anyway, we drove about 100 miles (200 there and back) to my father in law for a New Years party, and I had to use the block heater to start her up in the morning of january 1st (mountain cabin in Canada... you get the picture). That's when I noticed the vacuum hoses coming out from the big rubber plug on top of the intake were both snapped... so the car was running with no FPR (driver side hose) and God knows what else (passenger side hose), but other than lacking in power, it all was good. My mechanic ordered a full set of hoses, but they're still in the mail somewhere (for a bloody month!) - you just can't get those anywhere around here and they were snapped in such a place you can't just fix them with tape .
And just last week, she shut off once more as I was leaving work. Started again - the engine would pause and pick up many times (to visualize: "brrmbmbmbmbmbm-pause-bmbmbm...etc"), sometimes pause long enough to stall, it would still restart but die again soon after, eventually refusing to start at all.
Another dead ignition coil. Perhaps it was just a faulty replacement part? Perhaps it got worn by having to work with a dying distributor? Well, we replaced it again, and all was good... two days later I felt the engine pause for a fraction of a second. A few minutes later it paused again and the "check engine soon" light went on (for the first time!). I made it safely to work, but i wouldn't dare drive back home... if she crapped out on Montreal's highway 40 west during rush hour, I'd jam half the bloody island. When we were unloading her from the platform, she started up (very rough, but I'm sure it was just the cold weather) but only for a couple of seconds. Shut off before the engine could warm up enough for smooth running, and wouldn't start again. It did start again the next day, but for even shorter - maybe two seconds at most.
The code I can get using the paperclip technique is "32", meaning EGR failure. Doubt it... must have been triggered by that "misfire", when the engine paused while driving - the cyllinder getting a squirt of gas, but then no spark, another squirt at the next cycle and when that fired, the ECM may have registered that as a rich mix and triggered the code... or am I wrong?
The fuel pump is working for sure - I can hear it, and I can even smell the fuel being injected, but not ignited. I doubt it has anything to do with injectors, either... by now, I'm sure another ignition coil went bad.
But what can be causing this?? It seems to me like it's frying ignition coils one after another. Could it have anything to do with the broken vacuum hoses? The mechanic checked the harness and all cables are good, so it might be the ECM itself that's gone bonkers. But could there be anything else? Remember my vacuum hoses are down, too... I'm worried sick here and I'd be very grateful for some useful advice
I started having issues with my car (1986 Camaro SC 2.8 MPFI) last summer - it was running beautifully, no problems of any kind... and all of a sudden, the engine just shuts down when accelerating from traffic lights. RPM gauge drops down to 0 and there's no power. As i stopped, I heard the engine still puffing irregularily ("puff... puff... .... kapuff... puff..."). Shut it down, tried to start again - it just cranked and wouldn't fire up.
My mechanic narrowed the problem down to a blown ignition coil, replaced it (also, we installed a new distributor cap, spark plugs and spark plug cables) - and the car ran beautifully for about 4 months, when it crapped out in a very similar way again - just entered the highway, started picking up speed - the engine paused for a moment, picked up again, then shut off for good.
This time the problem was a rusted distributor - we've replaced the whole thing with a brand new one, and "Cammy" ran beautifully again for another 3 months. A bit later I noticed a lack of power, which I later tracked down to a vacuum leak (with the help of this forum ). Anyway, we drove about 100 miles (200 there and back) to my father in law for a New Years party, and I had to use the block heater to start her up in the morning of january 1st (mountain cabin in Canada... you get the picture). That's when I noticed the vacuum hoses coming out from the big rubber plug on top of the intake were both snapped... so the car was running with no FPR (driver side hose) and God knows what else (passenger side hose), but other than lacking in power, it all was good. My mechanic ordered a full set of hoses, but they're still in the mail somewhere (for a bloody month!) - you just can't get those anywhere around here and they were snapped in such a place you can't just fix them with tape .
And just last week, she shut off once more as I was leaving work. Started again - the engine would pause and pick up many times (to visualize: "brrmbmbmbmbmbm-pause-bmbmbm...etc"), sometimes pause long enough to stall, it would still restart but die again soon after, eventually refusing to start at all.
Another dead ignition coil. Perhaps it was just a faulty replacement part? Perhaps it got worn by having to work with a dying distributor? Well, we replaced it again, and all was good... two days later I felt the engine pause for a fraction of a second. A few minutes later it paused again and the "check engine soon" light went on (for the first time!). I made it safely to work, but i wouldn't dare drive back home... if she crapped out on Montreal's highway 40 west during rush hour, I'd jam half the bloody island. When we were unloading her from the platform, she started up (very rough, but I'm sure it was just the cold weather) but only for a couple of seconds. Shut off before the engine could warm up enough for smooth running, and wouldn't start again. It did start again the next day, but for even shorter - maybe two seconds at most.
The code I can get using the paperclip technique is "32", meaning EGR failure. Doubt it... must have been triggered by that "misfire", when the engine paused while driving - the cyllinder getting a squirt of gas, but then no spark, another squirt at the next cycle and when that fired, the ECM may have registered that as a rich mix and triggered the code... or am I wrong?
The fuel pump is working for sure - I can hear it, and I can even smell the fuel being injected, but not ignited. I doubt it has anything to do with injectors, either... by now, I'm sure another ignition coil went bad.
But what can be causing this?? It seems to me like it's frying ignition coils one after another. Could it have anything to do with the broken vacuum hoses? The mechanic checked the harness and all cables are good, so it might be the ECM itself that's gone bonkers. But could there be anything else? Remember my vacuum hoses are down, too... I'm worried sick here and I'd be very grateful for some useful advice
Last edited by Jonboy2312; 03-07-2009 at 07:29 PM.
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Re: Need help! Blowing ignition coils etc
Anyone?
Please, any, even the vaguest ideas might be helpful
Please, any, even the vaguest ideas might be helpful
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It has nothing to do with hoses.
If coils keep going: simultaneously replace the coil and ignition module.
Happy Racing!
If People Drove Any Slower They’d Be Going Backwards
How bout those dorks too scared to drive without headlights in the day time!
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Re: Need help! Blowing ignition coils etc
check your igntion module like stated above, check your engine to chassis grounds, i no that can cause problems if the engine is not getting a good ground or intermittently looseing ground, it will actually melt them by trying to ground the coil through the ground wire in the harnnes, instead of the engine.
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Re: Need help! Blowing ignition coils etc
I think it's the ECM itself...
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
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Re: Need help! Blowing ignition coils etc
I think it's the ECM itself...
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
when u say the wiring seems to be fine, does that meen u ohmned the pcm ign output to the ign coil input? or just looked for obvious melted wires, smoke, or severed wires.
try shaking the main harness down, all the way to the passenger side harnness. has the vehicle been wrecked? is there obvious body work done?
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Re: Need help! Blowing ignition coils etc
The car was never wrecked - what it did have, however, was obvious weather damage...
Anyway, the diagnosing and testing is complete and the verdict says it's the ECM. We're getting a brand new one, with part of the harness, too. Hopefully this will fix the problem once and for all. We should have that, plus the vacuum lines, on sunday (yes, the shop is open then... usually till about 11PM, too )
Anyway, the diagnosing and testing is complete and the verdict says it's the ECM. We're getting a brand new one, with part of the harness, too. Hopefully this will fix the problem once and for all. We should have that, plus the vacuum lines, on sunday (yes, the shop is open then... usually till about 11PM, too )
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Re: Need help! Blowing ignition coils etc
Okay, it seems the problem has been solved, and it was indeed a faulty computer. So, at long last, everything works as it should.
It was so frustrating... the engine has been nearly fully rebuilt last summer (stripped down, cleaned up and reassembled with new gaskets all over, new cables, new water pump, etc). All the ignition components are new, too... That's not to mention non-engine related things, like new brakes, tranny, rebuilt diff... And after all that, this persistent problem was driving me nuts like nothing else in this world.
Now with that out of the way, it's back to bodywork!
The left quarter panel is now done, the right one will have to be fixed too (the wheel wells were rebuilt last year), the rocker panels are done... I'm getting a pair of nice doors this week and I'll still need to get two brand new fenders later on. Whew... lots of work but I'll try my best to finish by summer. I might even get a new floor if all goes well
It was so frustrating... the engine has been nearly fully rebuilt last summer (stripped down, cleaned up and reassembled with new gaskets all over, new cables, new water pump, etc). All the ignition components are new, too... That's not to mention non-engine related things, like new brakes, tranny, rebuilt diff... And after all that, this persistent problem was driving me nuts like nothing else in this world.
Now with that out of the way, it's back to bodywork!
The left quarter panel is now done, the right one will have to be fixed too (the wheel wells were rebuilt last year), the rocker panels are done... I'm getting a pair of nice doors this week and I'll still need to get two brand new fenders later on. Whew... lots of work but I'll try my best to finish by summer. I might even get a new floor if all goes well
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Re: Need help! Shutting off while driving...
Okay... replacing the computer seemed to help at first, but then my car shut off twice while warming up in the morning (suddenly, as if by a kill switch), and once while driving (engine stopped for a second then resumed right after). It was working perfectly on the way back, however, and on the next day.
Then I realize what it was that was different whenever it was fine... THE HEATER. It seems like those problems only occur when the heater is on. If I leave the heater at 0, nothing weird happens. Oh, and doesn't the heater have a lot to do with EGR? I did get the EGR fault code before, afterall... so maybe that's it?
Then I realize what it was that was different whenever it was fine... THE HEATER. It seems like those problems only occur when the heater is on. If I leave the heater at 0, nothing weird happens. Oh, and doesn't the heater have a lot to do with EGR? I did get the EGR fault code before, afterall... so maybe that's it?
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Re: Need help! Shutting off while driving...
erg has nothing to do with the heater, sounds like you hvac control circuits are itermittintly shorting your ign circuit. id pull the radio out and inspect for damaged/melted wires.
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Re: Need help! Shutting off while driving...
Picked up my wife at her university, drove almost all the way home, stopped at a garage to get an appointment for alignment, went back to the car, started it... and called a tow truck after the car shut off after about 3 seconds and wouldn't start again.
It seemed like the engine was trying to catch on the moment the key was turned, but then the ignition shut off right after and it would just crank with no results. It's like... you turn the key, and the moment there's contact one or two cylinders fire, then there's no more spark and it just keeps cranking. Eventually it got flooded so any further attempts would have been useless...
Any ideas?
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Re: Need help! Blowing ignition coils etc
I think it's the ECM itself...
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
All the symptoms suggest that the coil is dead. But when you unplug it, and plug it in again - all of a sudden it runs! We tried the old coil we thought was bad - it started on that one, too.
This is so frustrating! Vacuum hoses are now patched up, all the wiring seems to be just fine, sensors are okay - it's gotta be the ECM, it's gotta be.
The two wire connection between the coil and distributor is known to go bad. This is the one that is two wires with a connector on each end. I would just replace it.
Also check the wiring going to the coil around the brackets. Sometimes they will chaff through and short to ground.
RBob.
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Re: Need help! Blowing ignition coils etc
We'll check that again, then. All the cables tested fine, though...
Another idea I just had is the crankshaft position sensor. The symptoms I googled up sound almost exactly like my problem - engine suddenly stops while driving, then starts back up the next second... and it happens a couple of times over a couple of weeks until it shuts off for good and won't restart. In my case, it gets flooded after a few attempts, has to be towed home and has to sit till the next day, which is today - and it started, but then it shut off after about half a minute (halfway through the garage gate), restarted again, drove into the garage, I turned it off for the duration of the diagnostic hookup... but it wouldn't start again afterwards (it's sitting in the garage now).
The diagnostic tool reads no trouble codes. The codes we got the last few times were 32 and 54. 54 doesn't show up with the new ECM installed (and the fuel pump works perfectly, always has), 32 didn't come up again either, but when we get the diagnostic computer to test the EGR directly, it comes up red - no response / dead. Well, that will have to be replaced, but surely it wouldn't cause the ignition to just shut off like that?
We're so desperate at this point that we've started to look for a carburated 305 motor and a matching tranny (daily driver, so no 350s...). It would be a shame to go that way, though, because this 2.8 is in great shape and has very low mileage on it... and is a really sweet, smooth little engine when it works. A lot of work went into it already, too... new gaskets, seals, cables, entire distributor assembly, coil, water pump...
Then again, a carburated 305 doesn't rely on any wonky electronics to run... right? And the MPG should stay about the same, as a 305 wouldn't have to put so much effort to move this car (which seems just-just-borderline too heavy for the 2.8)
I'm absolutely torn here :/
Another idea I just had is the crankshaft position sensor. The symptoms I googled up sound almost exactly like my problem - engine suddenly stops while driving, then starts back up the next second... and it happens a couple of times over a couple of weeks until it shuts off for good and won't restart. In my case, it gets flooded after a few attempts, has to be towed home and has to sit till the next day, which is today - and it started, but then it shut off after about half a minute (halfway through the garage gate), restarted again, drove into the garage, I turned it off for the duration of the diagnostic hookup... but it wouldn't start again afterwards (it's sitting in the garage now).
The diagnostic tool reads no trouble codes. The codes we got the last few times were 32 and 54. 54 doesn't show up with the new ECM installed (and the fuel pump works perfectly, always has), 32 didn't come up again either, but when we get the diagnostic computer to test the EGR directly, it comes up red - no response / dead. Well, that will have to be replaced, but surely it wouldn't cause the ignition to just shut off like that?
We're so desperate at this point that we've started to look for a carburated 305 motor and a matching tranny (daily driver, so no 350s...). It would be a shame to go that way, though, because this 2.8 is in great shape and has very low mileage on it... and is a really sweet, smooth little engine when it works. A lot of work went into it already, too... new gaskets, seals, cables, entire distributor assembly, coil, water pump...
Then again, a carburated 305 doesn't rely on any wonky electronics to run... right? And the MPG should stay about the same, as a 305 wouldn't have to put so much effort to move this car (which seems just-just-borderline too heavy for the 2.8)
I'm absolutely torn here :/
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Re: Need help! Blowing ignition coils etc
A carb'd 305 won't come near the fuel mileage the 2.8 MPFI set is providing.
When the engine floods hold the go-pedal on the floor while cranking. That invokes a clear flood mode (greatly reduced injector PW).
Anyway, the crank sensor is actually built into the distributor. It is the star wheel on the upper part of the shaft, the reluctor assembly, and the pickup coil.
If the engine is usually hot when this happens I would also go after the pickup coil and the ignition module. The pickup coil may be intermittent which is common and will cause the exact issues you are having.
A bad ignition module usually gives some trouble but then dies. But one never knows.
For 'checking' the two wire set that I mentioned previously. Since the problem is intermittent, you would need to put an ohm meter on the the opposing connectors. See that it reads very low ohms, then flex the wire and gently pull on it.
Then move the DVM to the other wire and do the same.
If the ohm reading starts jumping around then the wire has an internal break. This is the common failure mode of that piece. The wire usually breaks internally where it exits the coil end connector.
RBob.
When the engine floods hold the go-pedal on the floor while cranking. That invokes a clear flood mode (greatly reduced injector PW).
Anyway, the crank sensor is actually built into the distributor. It is the star wheel on the upper part of the shaft, the reluctor assembly, and the pickup coil.
If the engine is usually hot when this happens I would also go after the pickup coil and the ignition module. The pickup coil may be intermittent which is common and will cause the exact issues you are having.
A bad ignition module usually gives some trouble but then dies. But one never knows.
For 'checking' the two wire set that I mentioned previously. Since the problem is intermittent, you would need to put an ohm meter on the the opposing connectors. See that it reads very low ohms, then flex the wire and gently pull on it.
Then move the DVM to the other wire and do the same.
If the ohm reading starts jumping around then the wire has an internal break. This is the common failure mode of that piece. The wire usually breaks internally where it exits the coil end connector.
RBob.
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Re: Need help! Blowing ignition coils etc
When the engine floods hold the go-pedal on the floor while cranking. That invokes a clear flood mode (greatly reduced injector PW).
Anyway, the crank sensor is actually built into the distributor. It is the star wheel on the upper part of the shaft, the reluctor assembly, and the pickup coil.
If the engine is usually hot when this happens I would also go after the pickup coil and the ignition module. The pickup coil may be intermittent which is common and will cause the exact issues you are having.
A bad ignition module usually gives some trouble but then dies. But one never knows.
For 'checking' the two wire set that I mentioned previously. Since the problem is intermittent, you would need to put an ohm meter on the the opposing connectors. See that it reads very low ohms, then flex the wire and gently pull on it.
his is the common failure mode of that piece. The wire usually breaks internally where it exits the coil end connector.
Another bit of info that might help, although this was with the previous ECM. The ignition coil was powered with the key out of the ignition, out of the car itself for that matter... and would no longer be powered with the ignition on.
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Re: Need help! Blowing ignition coils etc
Having replaced the whole distributor eliminates the ignition module and pickup coil. I read through the thread but have forgotten some of what has already been done.
No cam sensor in the 2.8l system either.
It almost sounds like the power to the coil is being lost. However, that would also mean that power to the ignition module will also be lost. If that happens then the ECM shouldn't get DRP's and it will stop firing the injectors. Which of course means that the engine wouldn't be flooding.
Does the car have a tachometer? If so, unplug the wire for it at the coil. IIRC there is a white wire off of the coil with a fast-on type of connector. The tach lead goes to it. Just unplug it to take the tach out of the equation.
At this point because it is so intermittent I would be start by putting some wires to the coil + feed and block and running them into the car. Then connect a DVM on DC volts scale. Then when the engine dies you can see if the coil power is lost.
I think it is going to take checking/eliminating one thing at a time until the issue is found.
Unplugging the BYPASS/EST connector takes the ECM out of the EST control. The spark timing will run from the base setting plus some add-in timing at RPM.
RBob.
No cam sensor in the 2.8l system either.
It almost sounds like the power to the coil is being lost. However, that would also mean that power to the ignition module will also be lost. If that happens then the ECM shouldn't get DRP's and it will stop firing the injectors. Which of course means that the engine wouldn't be flooding.
Does the car have a tachometer? If so, unplug the wire for it at the coil. IIRC there is a white wire off of the coil with a fast-on type of connector. The tach lead goes to it. Just unplug it to take the tach out of the equation.
At this point because it is so intermittent I would be start by putting some wires to the coil + feed and block and running them into the car. Then connect a DVM on DC volts scale. Then when the engine dies you can see if the coil power is lost.
I think it is going to take checking/eliminating one thing at a time until the issue is found.
Unplugging the BYPASS/EST connector takes the ECM out of the EST control. The spark timing will run from the base setting plus some add-in timing at RPM.
RBob.
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Re: Need help! Blowing ignition coils etc
Thanks for all the advice... I'll try every little bit of it.
So the part that's equivalent to a crankshaft position sensor is inside the distributor itself - would that be this 6-tipped star element in the overhead view?
Well, that's what my mechanic found out - no power to the coil when the symptoms actually occur. It's like this - the coil had no power when we cranked (of course not counting the periods when everything worked fine), but it WAS powered when the key was out of the car. Is this normal??? I can't imagine this to be normal... Please, do you have any ideas what such behavior indicates?
Anyway, that's when we replaced the ECM. Everything seemed fine for a few days, then the car shut off when warming up and had a brief cut-out while driving... then no problems at all over the next few days... and then it died after a brief parking on a shopping run - so it's back to square 1.
I just feel like banging my head against the wall until I draw blood... this has been going on for months and months now, and everything logically related has been replaced already I had arrangements for bodywork and painting already, after saving up for it for a whole year... I'm pretty much in deep, deep despair now
Okay, so now about following your advice... does the tach communicate with the ECM? Maybe it's the tach that's faulty? If it suddenly indicated 0 while being connected to the whole system, what would the ECM do? I know for sure some previous owner tampered with the instrumentation. It's a fully optioned car that has been stripped of AC at some point (the control panel was replaced with a non-AC one, but the buildsheet says there's AC and there's still an AC bracket on the engine) and stripped of the cruise control switches (has a basic wiper lever, but the cruise control unit is still in the car).
And finally... You suggest unplugging the "BYPASS/EST" connector. Does that mean that with the ECM no longer having anything to do with spark control, the engine will run anyway?
This could be a life-saver... the repeated towings (after everything seems "perfect, for sure this time"), over and over again, killed most of the humble savings I had I'll have to try this.
Thanks again!
So the part that's equivalent to a crankshaft position sensor is inside the distributor itself - would that be this 6-tipped star element in the overhead view?
Then when the engine dies you can see if the coil power is lost.
Anyway, that's when we replaced the ECM. Everything seemed fine for a few days, then the car shut off when warming up and had a brief cut-out while driving... then no problems at all over the next few days... and then it died after a brief parking on a shopping run - so it's back to square 1.
I just feel like banging my head against the wall until I draw blood... this has been going on for months and months now, and everything logically related has been replaced already I had arrangements for bodywork and painting already, after saving up for it for a whole year... I'm pretty much in deep, deep despair now
Okay, so now about following your advice... does the tach communicate with the ECM? Maybe it's the tach that's faulty? If it suddenly indicated 0 while being connected to the whole system, what would the ECM do? I know for sure some previous owner tampered with the instrumentation. It's a fully optioned car that has been stripped of AC at some point (the control panel was replaced with a non-AC one, but the buildsheet says there's AC and there's still an AC bracket on the engine) and stripped of the cruise control switches (has a basic wiper lever, but the cruise control unit is still in the car).
And finally... You suggest unplugging the "BYPASS/EST" connector. Does that mean that with the ECM no longer having anything to do with spark control, the engine will run anyway?
This could be a life-saver... the repeated towings (after everything seems "perfect, for sure this time"), over and over again, killed most of the humble savings I had I'll have to try this.
Thanks again!
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Re: Need help! Blowing ignition coils etc
It would be more correct to state that these pieces of the distributor provide the crank position signal.
The tach is not connected to the ECM. It is attached to the coil - (negative terminal). Which is why I suggested unplugging it. If the tach goes bad they can prevent the engine from running.
You said no power to coil when engine wouldn't start, and then power with the key out. Stryder's suggestion is on the right track. Note that the ECM doesn't have anything to do with the power to the coil. It is all in the ignition switch and related wiring and fuses.
There should not be power to the coil when the ignition switch is off. And power to the coil at anytime the ignition switch is on or cranking.
The ignition switch is activated by a rack and gear from the key/tumblers. The switch is located further down the column. I would start by trying to verify that something in that area is bad. Pull the power plug from the coil and connect a DVM to the terminal of the heavy pink wire. That is the power feed to the coil. DVM grounded to engine block and on a DC volts scale.
Then while observing the DVM turn the key on and off, maybe even a little cranking. See if the voltage is on while the key is on or cranking, and off when the key is off. Jiggle the tumbler assembly and see if the voltage comes & goes. Tap on the column, if a tilt column move it while observing the coil voltage.
If it doesn't work as it is supposed to then it is time to dig into the column. I know that there have been posts here of the column breakdown. Try a search on column while using 'Vader' as the author. That may bring up a post with a picture.
RBob.
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Re: Need help! Blowing ignition coils etc
Whew... okay, SITREP:
The car is now in 'dead' mode, it won't fire up no matter what. Perfect for testing.
Unplugging the tach made no difference. Got a slight puff from one cylinder but that was probably coincidence (also, when the ignition failed completely on friday, I was getting the same 'puff' the moment I turned the key, and then just cranking and no fire).
My mechanic already tried it way before with the EST cable unplugged - no go. And as I showed up today, he was well underway to get into the column and the ignition switch already. Stryder, I think you're on to something... let's hope you're right!
I had a good look at it with the underside of the dashboard taken off - the wiring is a fugly hack job - at some point my car had some funky alarm system, which was removed (much like the AC and the cruise control). There's a switch next to the light under the driver side dashboard which seemingly doesn't do anything, there are motion sensors under the dashpad overhang, and some tangled thin cables taped together sloppily... whoever did this to her was a butcher I don't think any of that does anything anymore, but.. who knows? Anyway, there should be some more progress tomorrow - please keep your fingers crossed!
My new fenders arrived this morning, it was a welcome morale boost...
The car is now in 'dead' mode, it won't fire up no matter what. Perfect for testing.
Unplugging the tach made no difference. Got a slight puff from one cylinder but that was probably coincidence (also, when the ignition failed completely on friday, I was getting the same 'puff' the moment I turned the key, and then just cranking and no fire).
My mechanic already tried it way before with the EST cable unplugged - no go. And as I showed up today, he was well underway to get into the column and the ignition switch already. Stryder, I think you're on to something... let's hope you're right!
I had a good look at it with the underside of the dashboard taken off - the wiring is a fugly hack job - at some point my car had some funky alarm system, which was removed (much like the AC and the cruise control). There's a switch next to the light under the driver side dashboard which seemingly doesn't do anything, there are motion sensors under the dashpad overhang, and some tangled thin cables taped together sloppily... whoever did this to her was a butcher I don't think any of that does anything anymore, but.. who knows? Anyway, there should be some more progress tomorrow - please keep your fingers crossed!
My new fenders arrived this morning, it was a welcome morale boost...
Last edited by Jonboy2312; 03-09-2009 at 09:09 PM.
#22
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Re: Need help! Blowing ignition coils etc
I would do my best to remove all foreign wiring, as this could be your problem. Different alarms (And their installers!) work in many different ways. I have seen installers hook the disable to fuel pump, ignition wire, starter, switch power(Main) etc. Years ago, I worked on a friends car, who was having multiple problems with his fuel pump and while under the dash, I removed about 4 pounds of "Extra" wiring! Even I was amazed! His problems were gone. Worth a try. A lot of times, when people go to sell their car they just shortcut the wiring when they remove their aftermarket accessories, leaving live wires and who knows what else under the dash.
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Car: 86 berlinetta 92rs gfx
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Re: Need help! Blowing ignition coils etc
I would do my best to remove all foreign wiring, as this could be your problem. Different alarms (And their installers!) work in many different ways. I have seen installers hook the disable to fuel pump, ignition wire, starter, switch power(Main) etc. Years ago, I worked on a friends car, who was having multiple problems with his fuel pump and while under the dash, I removed about 4 pounds of "Extra" wiring! Even I was amazed! His problems were gone. Worth a try. A lot of times, when people go to sell their car they just shortcut the wiring when they remove their aftermarket accessories, leaving live wires and who knows what else under the dash.
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