Honestly almost had it
Re: Honestly almost had it
If the wires going to the injectors are no longer good would it be causing this problem, the injectors fire but cut off after a short amount of time. This is obviously a fuel problem, can I test the wires ? And if they are shorting out would that cause the computer to shut them off ?
Joined: Apr 2000
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From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
Anthony, it could be possible to do that. OHM the wires and move them around. Hard to say. The could be internally shorted(the injectors)
Re: Honestly almost had it
How many ohms should I be reading out of the wires & where could I get some new ones ? Mine are pretty burnt I'll take a picture when I get home & they're burnt to the point where you can see the wire inside it burnt through the plastic. I'll test them out but if the injectors are turning on doesn't that mean they're good? I'll still replace them don't want nasty wires.
Joined: Apr 2000
Posts: 3,938
Likes: 99
From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
2.5 OHMS, like Tuned Performance said. Unplug each one and test the injector. As for the wire, you can poke the insulation on each side of the burn mark and wiggle the wire to see if it shorts on the meter
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Joined: Sep 2011
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From: Spring Hill, Fl.
Car: 87 iroc-z
Engine: 454
Transmission: th350
Axle/Gears: 3.73
Re: Honestly almost had it
i think some pictures would really help at this point.
i've seen the injector wires get pinched under the metal air filter spacer, and have seen the wires burnt before, causing issues. you can buy new pigtails if needed.
http://www.autozone.com/fuel-deliver...-ohv/79638_0_0
i've seen the injector wires get pinched under the metal air filter spacer, and have seen the wires burnt before, causing issues. you can buy new pigtails if needed.
http://www.autozone.com/fuel-deliver...-ohv/79638_0_0
Joined: Apr 2000
Posts: 3,938
Likes: 99
From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
i think some pictures would really help at this point.
i've seen the injector wires get pinched under the metal air filter spacer, and have seen the wires burnt before, causing issues. you can buy new pigtails if needed.
http://www.autozone.com/fuel-deliver...-ohv/79638_0_0
i've seen the injector wires get pinched under the metal air filter spacer, and have seen the wires burnt before, causing issues. you can buy new pigtails if needed.
http://www.autozone.com/fuel-deliver...-ohv/79638_0_0
Supreme Member
Joined: Sep 2011
Posts: 2,080
Likes: 34
From: Spring Hill, Fl.
Car: 87 iroc-z
Engine: 454
Transmission: th350
Axle/Gears: 3.73
Re: Honestly almost had it
IF,...you need to change them, cut and splice 1 wire at a time or take a pic with your phone. just match up to your current wiring. it's pretty simple. it only goes on the injector one way IIRC?
Joined: Apr 2000
Posts: 3,938
Likes: 99
From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
Anthony....Is your tack wire hooked up? Does it bounce when trying to start?
There is should be a tach signal wire that goes to the tach on the HEI. This is the only wire that tells the injectors to fire. If there is no tach signal, the computer thinks the engine is not turning over and will not fire the injectors.
There is should be a tach signal wire that goes to the tach on the HEI. This is the only wire that tells the injectors to fire. If there is no tach signal, the computer thinks the engine is not turning over and will not fire the injectors.
Joined: Dec 2004
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From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Honestly almost had it
Anthony....Is your tack wire hooked up? Does it bounce when trying to start?
There is should be a tach signal wire that goes to the tach on the HEI. This is the only wire that tells the injectors to fire. If there is no tach signal, the computer thinks the engine is not turning over and will not fire the injectors.
There is should be a tach signal wire that goes to the tach on the HEI. This is the only wire that tells the injectors to fire. If there is no tach signal, the computer thinks the engine is not turning over and will not fire the injectors.
Joined: Apr 2000
Posts: 3,938
Likes: 99
From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
Another thing to ponder
Injectors are "hot" with key "on". ECM controls the ground for the injectors, causing them to spray fuel. ECM controls ground based on signal from distributor that distributor is turning. You won't have ground to the injectors without cranking the engine, or supplying a cranking signal as if the distributor was turning.
ECM knows the engine is being cranked. It should be supplying pulsed ground to the fuel injectors while cranking. Since you have power to the injectors, pulsed ground should make them spray fuel. Since you have no fuel spray, apparently there's a problem between the ECM and the injector when started..
Injectors are "hot" with key "on". ECM controls the ground for the injectors, causing them to spray fuel. ECM controls ground based on signal from distributor that distributor is turning. You won't have ground to the injectors without cranking the engine, or supplying a cranking signal as if the distributor was turning.
ECM knows the engine is being cranked. It should be supplying pulsed ground to the fuel injectors while cranking. Since you have power to the injectors, pulsed ground should make them spray fuel. Since you have no fuel spray, apparently there's a problem between the ECM and the injector when started..
Joined: Apr 2000
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From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
Sorry for the late reply, but what is the "HEI" ? and what should I be reading on the tach ? And honestly I'll try out anything just give me some time to kinda comprehend all this wiring lol. And what exactly do you want me to test ? I had a shower come in and I couldn't go out to work on the car today but tomorrow for sure I will.
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From: Chasing Electrons
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Re: Honestly almost had it
RBob.
Re: Honestly almost had it
I was reading over a few things and Bob lead me to test out the ground at the module which sends the signal to the computer. I'm going to test it out and see what happens, I remember when putting on my distributor the mechanic sort of bent a prong in the icm but we bent it back and I figured it'd be alright maybe it's not getting a good signal
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From: Chasing Electrons
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Re: Honestly almost had it
Sitting eating lunch and a thought came to mind, maybe the EGR valve is leaking exhaust into the intake. That will definitely cause the engine to stall at lower speeds.
RBob.
RBob.
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From: Chasing Electrons
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Re: Honestly almost had it
One way is to unbolt the valve and check if the pintle is seating closed. Maybe even temporarily block off the EGR ports and see how it runs.
Start up then sputter and die, yes. On a properly running engine opening the EGR valve at idle is an instant stall.
RBob.
And would it cause this problem I'm having?
RBob.
Joined: Apr 2000
Posts: 3,938
Likes: 99
From: Huntsville AL
Car: 88GTA
Engine: 5.7TPI
Transmission: Auto
Axle/Gears: 3.27
Re: Honestly almost had it
"If the wires going to the injectors are no longer good would it be causing this problem, the injectors fire but cut off after a short amount of time. This is obviously a fuel problem, can I test the wires ? And if they are shorting out would that cause the computer to shut them off ?"
"Start up then sputter and die, yes. On a properly running engine opening the EGR valve at idle is an instant stall."
RBob.
EGR issue wouldn't cause the injectors to turn off though, would it??
"Start up then sputter and die, yes. On a properly running engine opening the EGR valve at idle is an instant stall."
RBob.
EGR issue wouldn't cause the injectors to turn off though, would it??
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Joined: Sep 2011
Posts: 2,080
Likes: 34
From: Spring Hill, Fl.
Car: 87 iroc-z
Engine: 454
Transmission: th350
Axle/Gears: 3.73
Re: Honestly almost had it
man, go buy a noid light at harbor freight or somewhere.
if your worried about the EGR, cut a piece of sheetmetal the size of the gasket and bolt it where the gasket goes.
sounds to me like that "bent" module might be your problem? but you'll never know anything til you get a noid light. JS
if your worried about the EGR, cut a piece of sheetmetal the size of the gasket and bolt it where the gasket goes.
sounds to me like that "bent" module might be your problem? but you'll never know anything til you get a noid light. JS
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From: Chasing Electrons
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Re: Honestly almost had it
"If the wires going to the injectors are no longer good would it be causing this problem, the injectors fire but cut off after a short amount of time. This is obviously a fuel problem, can I test the wires ? And if they are shorting out would that cause the computer to shut them off ?"
"Start up then sputter and die, yes. On a properly running engine opening the EGR valve at idle is an instant stall."
RBob.
EGR issue wouldn't cause the injectors to turn off though, would it??
"Start up then sputter and die, yes. On a properly running engine opening the EGR valve at idle is an instant stall."
RBob.
EGR issue wouldn't cause the injectors to turn off though, would it??
RBob.
Re: Honestly almost had it
Cleaned the EGR and it did nothing. It wasn't clogged much but gave it a nice cleaning. Hooked up a computer to check for anything radical and the car seems to be fine. Mechanic decided to call out the ecm so I'm purchasing another one. Could killing the battery and then re-charging it putting it on the car more than once mess up the ecm over time? Just a question I had. And well just waiting on the ecm. I don't see why it would go bad but every thing else is there to keep her running except the start and stall.
Re: Honestly almost had it
Well it don't even stay running long enough to put it into any other gear. Today when the ecm was plugged it would just crank and crank and crank. Of course spray from starting fluid and it'll run I've taken out the ecm of the equation my mechanic has done stuff coming from him but not even be can figure it out. I appreciate everyones help a whole lot it's been great reading everyone's inputs. I hate to rack everyone's brains but thats just how problems go. Once again fuel pressure is there spark compression, but there's something wrong with the fuel and I just can't seem to find out what it is
Re: Honestly almost had it
Replaced: Fuel tank, fuel pump, sending unit, fuel filter, fuel pump relay, fuel pressure reg & I actaully bought a new tbi unit off a member, I told my mechanic to take off the one it had since it was stripped and I just decided to get another one. He said he changed it but there was no change to the car but I saw the part on the driver seat. Anyway i have been reading a lot and I stumbled upon an old thread where a guy literally changed almost everything and in the end a pinched fuel line was causing a start and stall problem. So today I'm going to go look and see if I find any crimps or pinches along the lines. I tested fuel pressure at prime but not when cranking so I'll make sure to do that too maybe try to keep it running with starting fluid and see if the pressure drops or stays when increasing the throttle
Joined: Jul 2003
Posts: 10,532
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From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: Honestly almost had it
This thread has me scratching my head. You say your mechanic really knows what he is doing, but I have a few questions. How did your mechanic set Initial timing with the engine only running off of starter fluid? You mean to tell me he sprayed, then cranked, then sprayed and cranked his way to 0* BTDC with the EST disconnected? Did he really set base timing, or is he full of it? Did you reconnect the EST at least? Also, you're stating you're getting spark, just not fuel. However in the very first few posts I am reading how the engine will start, but die shortly after, yet now I am reading it won't start at all. Well which is it? If it starts then stalls, then either you are losing fuel pressure (when you test for fuel keep the pressure gauge on the schrader valve for longer than a minute or two after shut down and see if pressure remains), or the injectors are causing driver overheating and shutting off on you...
Re: Honestly almost had it
To be very honest with you I have no clue as to how he set the timing. I didn't ask he had just said he set it and when I told him about the est wire & the whole process of disconnecting it and what not he said he knew so I then believed he did time it correctly & stating what you said I will now start questioning even more, and your saying the car had to at least be running maybe roughly but running in order to time it correct?
Supreme Member
Joined: Sep 2011
Posts: 2,080
Likes: 34
From: Spring Hill, Fl.
Car: 87 iroc-z
Engine: 454
Transmission: th350
Axle/Gears: 3.73
Re: Honestly almost had it
i hate to admit it, but i accidentaly pinched a fuel line while changing a fuel pump on a third gen once. it was TPI though. it ran but was down on power. it was fairly obvious to see when i crawled back under there and had a "DUHHO!", moment.
Joined: Jul 2003
Posts: 10,532
Likes: 204
From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: Honestly almost had it
And why would the injectors cause the driver to overheat ? If they were to be doing that
Re: Honestly almost had it
I'm going to do exactly that ! Might take me some time but I'll get it done! And yes it runs on starting fluid and my mechanic might not be the man for the job and since I'm only 18 he looks at me like a kid wanting a car and once I start telling him check this check that he just stares at in awe. I'm young but I know so much about this one car and well hopefully everything youre telling me to check pays off I'll get back to you and everyone else asap thanks a lot I appreciate it.
Re: Honestly almost had it
AND SHE'S UP AND RUNNING !!! THANK YOU ALL SO MUCH FOR ALL THE HEADACHES AND INPUT !! I FINALLY GOT HER RUNNING. So the problem was the ecm but after a new ecm it continued. Well we hooked up a battery booster at least that's what I call it and she turned one faster than ever. The mechanic had not set the timing well he had but like one of you all said how could he without it running well he messed with the dizzy a bit hit the spot and she stayed running. Well we unplugged the jumper and the car died ! He then told me your alternator is out, just replaced it car runs now and just need to set my timing and shes ready to go ! I'm grateful to have this site to help me out and for everyone here who was stumped by this. Thanks all !
Joined: Dec 2004
Posts: 16,752
Likes: 996
From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Honestly almost had it
Congrats!
Reminds me of this thread where injector pulse was only when the battery was low .
https://www.thirdgen.org/forums/tbi/...o-350-tbi.html
Reminds me of this thread where injector pulse was only when the battery was low .
https://www.thirdgen.org/forums/tbi/...o-350-tbi.html
Last edited by Tuned Performance; Mar 16, 2017 at 06:48 PM.
Joined: Aug 2009
Posts: 1,821
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From: Central California
Car: 92 Camaro RS
Engine: LO3
Transmission: T5
Axle/Gears: stock
Re: Honestly almost had it
Hey, great to hear! Knew if you kept at it you were bound to get it going.
I'm sure it was an annoying way to find out lots more about your car and how it works
but lessons like that seem to be remembered longer!
Have fun with your car!
I'm sure it was an annoying way to find out lots more about your car and how it works
but lessons like that seem to be remembered longer!
Have fun with your car!
Last edited by henryd3; Mar 16, 2017 at 06:48 PM.










