Ok, here is the problem. It wont start. Here is a run down of what I change before the problem.

I removed the smog tubes and the rubber hoses from behind the dist. This ended up breaking the ignition module "dont ask how".

I replaced the module, and did a few mods like Msd coil, BBK afpr, removed and ported the plenum, air foil, and K&N cone filter.

Ok, I have timed and retimed the dist. I pulled it completely out and checked everything. New module, cap and rotor button is good. Gear looks good.

I am getting spark at the plugs, and have 48-50 fuel pressure.

Oh yeah, I checked the IAC and the TPS aslo. " cleaned the TB"

I am thinking about squirting some gas in the plenum to see if it will start.

The battery is good, the starter cranks good, the plug wires are in the right sequence on the cap, what can it be.


help! help!

 

Distributor off 180 degrees from the crank?

 

But I put the dist in on the compresson stroke with the #1 piston at TDC. Also the rotor button is pointed at #1 cylinder. Isnt that the right way? If not then it is screwed.

 

Try some fuel in the TB if you think it may be a fuel dedlivery issue. Since you have had some of the intake apart, recheck the injector harness and grounds on the rear of the right head. Might as well take a peek at the INJ fuses, too. You can test for the 12VDC source at any of the injectors. The ECM switches the grounds of the injector ciruit to operate them, so grounding is very important.

This is all presuming that the ignition is correectly timed, of course.

 

I was thinking about trying the fuel in the TB idea. It shouldnt hurt anything. and will rule out the fuel system.

As far as the timing. Like I said I put my finger over the #1 cylinder spark plug hole and had a friend crank the motor. When the pressure blowed my finger back, I checked the timing marks.

I then had to turn the crank to line up the timing mark and tab. Then the dist dropped right into place with the rotor pointing at the #1 cylinder. Also I had marked the cap before I removed it and It lined up also with the rotor and #1 plug wire.

This should be right or very close?

I will check the ground and volts at the injectors. Will it have 12 volts to the injectors at all time as long as the key is on or just when cranking the motor?

 

With the key on you should have 12 volts from each injector pin to ground (test light works good for this). Next hook the light across the pins in the harness and crank the engine, the light should flash on and off. This tells you that the ECM is seeing the tach pulse from the distributor and is firing the injectors.
Since you had the dist out and replaced the module, make sure ALL connections are hooked up properly.

 

Try starting fluid, if it starts and runs fine then your new module is bad. If it dies after starting then like Vader said you may have missed one of those ground straps connected to the smog lines behind the heads.

A better way(for me, at least) to set timing is to remove the #1 plug and actually put something like a thick wire in the hole and jam it into a valve relief so you can feel where the piston is in it's travel, then turn the motor over by hand and you'll feel tdc.

By the way, make sure your new ignition module is connected correctly.

 

Is it possible that when the module broke that the plug or wire may have gotten cracked or broke? It seems fine, and I did test it to see it was getting power.

I will do some checking and let you guys know.

 

Just wondering.....is the car even attempting to start? Or is it just cranking away with no cough at all? That might narrow it down a little

 

If you have spark and fuel and coughing, never mind the check reverse the 180 leads and see if it starts.

 

Just one cough when I first tried to start it after putting the dist back. Then it just cranks and cranks.

 

Well I had the same problem and I was sure I'd got the distributor in OK because I had the valve covers off and I could watch the valves, and I was really carfull. But I still got it 180 out.

I couldn't face taking the distributor out again - it was 100 F in the garage - so i just took off the HT wires and put them all back 180 out - no one else will be able to service the engine - but anyway I did that, turned the key and such a sweet sound it fired up.

The only other thing if you are really really sure the timing is OK, is you might not be sending a signal to the computer to tell it to gave the injectors a squirt. The good thing about the cross fire throttle body is you can enjoy watching the injectors working.

You may get a tiny drop of gas from a drip or an injector opennning momnetarily when you switch on, and that is enough for the cough.

If it is the same as the 83 model, the module connections to the computer via a three wire plug into the distributor and from there to the computer. If you had all that out when you changed the module, it would be easy to not get the connection made, and that would mean no fuel. It might be broken but not easily noticed.

If you were having problems around the back of the distributor, you may have a broken wire, thats the routing to the computor.

 

Ok, I did some more checking.

The ground on the back of the head is OK. I turned the key on and checked the injectors, they had 12v. I checked the wiring harness that goes from the dist to the coil. It was fine, I used a digital volt meter. I re-checked the coil and it has 12v.

Ok, when I checked the 4-wire connector that goes to the module in the dist, It had very low voltage. Like .01 or .05. I checked my chiltons and I will re-check it with a volt meter and a light.

Am I right when I read in the book, that I have to hook the volt meter to one wire and ground it and then hook up the light to another wire and ground it. All being on the 4-wire harness on the back of the dist. Sort of getting a loop. Or am I just reading this wrong.

I have not tried the fuel in the TB yet. I have the afpr set at 48-50. This would not flood the motor right. The plugs seem dry. And I am getting fire to the plugs.


Are there a sure fire way to make sure the dist is not 180* off?

thanks for any help

 

48-50 PSI should be fine. I run my 305TPI at 48.

When I put my engine back together for the first time I did put the dist in 180* off. The car wouldn't start. I turned the top of the dist (like when you adjust the timing) all the way until it stopped. I had it so far back around that the car would actually run. It was running like total crap but it ran. When I checked the timing it turned out to be like 28*retarded. I knew at this point that I must have the dist in backwards. I pulled it up about 2 inches turned it 180* put it back in. Put the top of the dist in a more realistic timing position and it fired right up. I set the timing to 6* and it purred.

It really is quick and easy to turn it 180*
At least if you tried it you could rule that out as a possibility.

My $.02

 

you could always just pull the valve cover off to assure your on the compression stroke!!

i'm pretty sure you can use the valve cover gasket again..

 

This problem is really getting old. I have tried pulling the dist half a dozen time. Each time checking for TDC and even trying to rotate the dist as far as I can while someone cranks it.

If it is 180 out then I need a sure fire way to get it wright. I have tried the thumb over the #1 spark plug hole, I have tried getting it to TDC with the valve cover off while checking the valves.

The sad thing is that I had it running after all the mods. I parked it and then went out to start it a few days later and nothing. It just cranked and cranked. thats why I thing there is something else wrong. But I will try anything at this point.

 

I had a similar problem where my car was running fine one night. Come home park it. Can't get it started the next morning. What I learned from that was

A. Autozone has a machine that checks ign. modules
B. The guy told me that it wasn't 100% accurate.
C. When you buy a new dist. from Autozone it comes with a new module.
D. A new dist and module fixed my problem. Fired right up as soon as I put the new dist. in.
E. It cost about $125.

Hodge

 

I might have to consider a new dist. Sad thing is that I was going to change to carb in the summer so I would be changing dist also.

Im going to try the gas in the TB tonight. And check the timing for the 100th time.

 

I had a similar problem where my car would not turn over fuel pressure readings were within mfg specs and i was getting spark but it would not turn over, but if i sprayed some starting fluid into the throttle body after a few cranks its would fire, turns out the injectors were really dirty and needed to be cleaned.

 

UPDATE!!!

I tried the fuel in the plenum trick, and it tried to start. It did run for a second or two. So I re-check the fuel at the fuel rail, which I had 2 days before, and the pressure went to 50 psi then steadly dropped off to zero.

Ok, In my mods I had put on a BBK afpr, so I found my stock one and swapped as to rule it out. Had the same 50 psi then dropped to zero. I have a fitting I made to hook up directly to the feed fuel line before the afpr. I will check there to see what I have.

What PSI should I have on the main feed line before the afpr?

Also does this mean that the pump is going bad, or maybe an injector stuck open. This is the only thing I can think of.

What fuel pump should I go with if its bad? And should I drop the tank or cut a access panel?

 

Yep, stuck injector or bad checkvalve in the pump. To do the pump right, drop the tank. It is a pain, but it will save you possible future problems.

 

I will drop the tank. I have already dropped it twice before. Once when I changed from tbi to tpi, and then another time the 3 inch hose on the pump cracked and was not pumping to the motor. That ended up costing 300 bucks by the time I found out it was a 30 cent part.

If it is the injectors, What can I do. Besides send them off to be cleaned and balanced.

 

i could probably get ya my old ones... they looked like new when i took them out!!!

and i know there ok

 

Bluegrassz, can't wait till you get this figured out, cause I am having the same problem. I just put headers on, rebuilt heads, coil, plugs, wires, etc. When I cranked it for the first time it fired up right away. I was so happy nothing leaked or blew up in my face. A week later I went to flush the coolant and refill it, and after running for almost 10 minutes, i cut her off, and then went to start it back up. Won't start though. Tried it again the next day, fired right up. Later last night, no start. Gonna try again tonight. I think I am getting air bubbles in the fuel system though. When I press the Schrader valve on the fuel rail, air pisses out, then fuel dribbles. Any ideas??? Please help, getting desperate!!!

 

Replace them is about the only real option. You said you had them cleaned once before? If so and one is sticking now...time for new ones, they don't last forever (unfortunatly)

 

If you are getting air in your fuel rails try filling the tank to the top and see if it still does it. If that "fixes" the air problem then you have a line in the tank leaking and sucking in air. If that doesn't fix it I would check the flex lines in the engine bay and check the regulator.

 

I may have to take you up on that. Either way I would be out 80 bucks, If im lucky. 80 for cleaning and matching, and 80 for a new GM pump.


MORLEY, I hadnt had them cleaned before. But I may need some new ones anyway.


ARDELS91A, you may have a leak in the small fuel line on the pump itself. Do you have a fuel pressure gauge? Check it at the schrader valve. You may also need to check the lines at the fuel rails. They may not be tight, I cant remember if they have o-rings or not on the lines.

 

OK good to hear it wasn't the timing.

Have you checked the pressure control valve which controls the flow of fuel back to the tank? That controls the back pressure in the fuel rail

If it has failed, it might open and stay open loosing the fuel pressure.

I think it is located near the distributor on your year.

 

man everyones car is doing this. ive got mine sputtering but wont fire. it was just cranking and cranking. ive got signs of life comming out now but im not quite there.

 

UPDATE!!!

Ok, I did some more checking last night. I put gas directly down the runners with the plenum off. The car started and reved to about 4 grand and died. I put my fuel pressure gauge directly on the feed line before the fuel rails. It went to 60 psi and then went to 40 and held. Is this enought pressure?

I also checked the injector wires. I am getting 12v with the ignition turned on, but nothing when it is cranked. This means my injectors are not firing right. What do I need to check to get my injectors firing again?

Also when I hooked the fuel line back up and turned the key to the on position I could hear fuel though the runners. Does this mean that the injectors are stuck open?

Thanks for any help. Vader, Hodge, you guys got any suggestions.

 

Yes, that should be enough. If you cycled the key off and on a couple of times it probably would have remained at a higher pressure.
Yep, sounds like the injectors are not firing. To get them firng you need to find the wire that provids the ECM with the ignition pulse and see if it is broken or shorted to ground. You may also have a bad ignition module.
To verify that the injectors are really stuck open you need to pull the fuel rails up with the injectors still in them. Get a container to catch any gas (cat litter pan works good) and put it under the injectors and watch them while someone turns the car on (don't crank it just yet). If the any injectors spray, run or dribble...replace it (or get them repaired/cleaned)
If they aren't leaking, have someone crank the engine and observe the injectors for operation.

 

could one of the wires that goes to the ignition module be the one that pulses the injectors? The 4-wire plug? Also should I have any volts going to the same 4-wire plug? When I checked it, I had very little like 0.1 or 0.5v.

Im pretty positive that the module is good.

Also does that mean the fuel pump is ok?

 

Sounds like your problem is definitely in the dizzy, either a bad pick up coil or a bad module. If the iECM isn't firing the injectors that measn it doesn't think the engine is moving. Or the ECM/wiring is bad. However, since you just replaced the module, and everything worked before you broke the other one, seems to me you got a bad one out of the box. Silly to assume something else randomly failed at the same time. Yes it is possible to get a bad electric part out of tehbox, happens ALL the time. And usually leads to weeks of frustration as you assume it's not the problem.

Maybe badgta can you lend you his while he grinds his rods down and gets his engine together. If not, then i reckon you're going to learn about the 'no returns on electrical parts' policy of every parts store i've seen, and buy a new module.

 

well ed, I bought the accel module new and put it on when I first had the problem. I had the motor started since then. I also took it back off and had advance check it, they said it was good.

I know that they say advance and autozone are not 100% sure, so is there a way to check it my self? And If I do check it, will I be 100% sure?


Also how can I check the 4-wire plug that goes into the module? Should it have any votage with the key on? IF so how much?

 

Like i said, if the injectors are not firing, then the ECM is either dead, the wiring is bad, or the ECM doesn't think the engine is moving (i.e. the dizzy isn't sending reference pulses.)

Reference pulses come from the modukle, which is fired by the pick-up coil. But if you have spark then at least something in the dizzy is working right. Doesn't mean it's sending reference pulses though. Off the top of my head i don't know how you'd verify you were getting refernce pulses without a scope, or at least a scan tool.

Even if the module worked for 5 minutes, it doesn't mean it's still good. And i wouldn;t consider the autozone test definitive either. You either need an oscilloscope or a scan tool, or you need to swap to a known good dizzy, or you need to replace something and cross your fingers, and unless you know something we don't, my first guess would be the new module.

 

I will give it a try. I have a new pick up coil. Cost about 7 bucks. I will put that in also.

 

ooohhh, thats cold dude....... but a good one

but. i'm not doing any grinding!!!!



damn, z... that car just want's to not be drove huh???

i'll go up my friends and get my old ones for ya.......... well get ya back on the road.......


p.s. ed, i got brand new ford racing 30lb for my stealth...... he he he

 

Recap
You have sparks OK
The engine will run if you add fuel directly
There is 12 volts at the injectors
40 psi fuel pressure constantly so that is enough
Wires were broken around the distributor, when the smog pump was worked on

I think on the 92, you get 12V to the injectors from the fuse box. The injectors are fired when the ECU computor earths the injector. This means the computor is not earthing the injectors.

You can check this 2 ways.
Listen to the injectors with a stethoscope or screw driver. Or connect a 12 V light emiting diode in place of the injector and see if it flashes.

There is one most likely reason in your case why the computor is not triggering the injectors. That is one of the four wires between the distributor and the ECU is not conneted properly.

From the wiring diagram it looks like you need to check the tan color wire. The other wires seem to work the ignition, so if the diagram is correct, must be ok for the sparks to work.

These wires were the ones worked on originally so they are most likely the problem. It is much less likely to be the ECU.

 

Andy That was what I had narrowed it down too. The only question I have is " Should any of the 4 wires have voltage to them when the key is on?" If so how much, because I am not getting anything right now.

 

I am not sure of the voltage, but you should get at least pulsed micro volts when you crank the engine, but nothing until the engine cranks.

The 12 V supply comes from the ignition to the distributor, and I am pretty sure the module sends a pulse of low voltage only when the ignition module fires so you wont see any voltage until you crank the engine.

You might try sticking a fine pin through the wires one at a time and seeing if there are microvolts between any of the wires and earth when you crank the engine. You can cover over with insulation tape afterwards.

If you get nothing it looks like the module is not feeding the ECU with a signal.

While the wire is peirced you can also check if it has continuity to the plug on the module and the module treminals.

The only thing though is it seems so unlikely that you actually broke a wire, which keeps leading back to a faulty module or brocken connector at the module.

Will the supplier let you try another unit. Unfortunatly so many spare parts are bad, straight from the store, you always have to suspect they are faulty.

 

Ok... If you have spark then you will also have injector pulse. The circuit carries 12 volts to the injectors and the computer grounds the injector circuit. Take a test light... with the injector unpluged... put a piece of wire in one side of the injector plug and clamp test light on to the wire... Have someone turn over the engine while you touch the test light on to the other side of the injector plug....

The test light should flash.. If it doesn't and all the fuses are good then the pcm is bad.. This is cut and dry....

Recap : 12 volts to one side of the injector connection..
PCM grounds the other side...

Just the same as a light bulb on and off.. If you have voltage, your loosing your ground which is controlled by the computer !!!

 

One other thing... .. If you do have spark and the fuses are good but no injector pulse...

1: Check the ground wires on the back of the heads
2: Verify the voltage reference signal for the computer (Vref)
To do this check the tps wire, Unplug the tps and check wires. does it have a 5 volt signal to one of them ? TPI should be the top one.. IF so get your self a pcm..

 

OK, When I checked the injectors, I used a digital volt meter.

I put the red wire to one side of the injector plug and grounded the black to the exhaust manifold. I got 12v with the ignition to the on position. I then checked the other side the same way. Got 12v. I then tried It with the motor cranking and nothing. I then ran the red to one side of the connector and the black to the other side and cranked it. Nothing.

I am going to check the continuity on the 4-wire plug.

Oh yeah the ground on the back of the head is fine. I had already checked it.

 

I was just having some trouble with my car not starting after doing some mods. I pulled the plenum and runners off and lifted the fuel rails and cranked the engine to make sure the injectors were firing. They weren't.

Did anyone ever notice that the connector that plugs into the IAT in the rear of the plenum is the exact same shape as the connector that goes from the coil into the distributor. Same exact shape and they are so close together. Well, I don't think I have to tell you what was wrong.


I plugged them into the right places and voila it started right up.

Moral... I'm recomending that you pull the plenum and runners and pull up the fuel rails just to make sure your injectors are firing. PITA but it's something you need to rule out.

One other thing to bring up is that if you aren't getting oil pressure then the ECU will turn off the Fuel Pump. Do you get fuel pressure the entire time that you are cranking or is it there and then dies when you start cranking?

Hodge

 

A volt meter will show 12 volts on both sides of the injector plug where a test light won't ... Start there with a test light...
You might wanna copy and print this and take it to the car...

Key On Engine Off
Probe injector connector with test light on both sides....
If it lights only on one side connector go to line A:
If it lights on both sides go to line B:

A: 1) Connect test light one side of injector plug and then probe the other side of harness with test light.. Important step here.. does it flash. If not go to next step.

3) Check TPS voltage with your volt meter. Should be center and bottom terminals together.. WHILE PLUGED IN... It should be
like .5 to 1 volt if its 4 volts PCM is in clear flood mode.. Replace TPS and fix car... if not go to next step

4) Verify VREF at upper TPS connector to ground. Should be 5 Volts with volt meter. If not than look for chaffed or broken wires in harness between the starter area and the coil. ( PinK wire with black tracer I believe ).. If 5 volts is there then Replace the PCM...

or

B: 1) Test light lights up on both sides of Injector harness with that injector unpluged ? Disconnect PCM.. It should now only light up on one side.. If so then Replace the PCM.. If it doesn't tell me and Ill look up to see which wire is shorted to power. thats it, it's not in the distributor if you have spark !!!

 

A volt meter will indicate 12 volts that carries no flow because of it's sensitivity.. a test light will only light up if there is a flow of voltage to ground. Also when you check the injector plug for a light on both sides, make sure the injector is unplugged.. If you follow this it should be the fix...

 

i had the same problem almost i had spark and fuel but it wouldent start and i changed everything. eventually advanced the timing by alot and got it running but later on it died again so i fixed the timing and it barely ran. well i didnt read all of above so dont flame when i say it but if you havent yet give the ecu a try it could be throwing off your timing buy not allowing anything to work together and jacking up the motors cordination thats my guess. my fix action: the bird became a project car (money pit) and i bought a el camino to commute in and haul parts for the bird.

 

I will get a new test light and check the injectors again. My old one bit the dust. Hopefully I can come up with a answer.

 

[Ok... If you have spark then you will also have injector pulse. ]


I hate to contradict another member but that staement is not always true. I had an identical problem with my 350 TPI that got worst when there was high humidity. I had mondo spark but no injector pulse. Unlikely that the computer fried but possible. What is possible would be that there is enough voltage to fire the coil but not enough to signal the ECM to fire the injectors. Before you go nuts make sure that the pickup coil wire is securely connected to the module and add a little ignition grease to the contacts. Also, since you were working back there, triple and quadruple check the 4-pin wires out of the module and establish continuity all the way to the ECM. Make sure you disconnect the battery and unplug the ECM connector before you try. Good luck,` hope this helps.

 

I ordered the 4-wire connector new from Gm. The original got is a little twisted "the plastic plug". So I am going to replace it. I dont think it is seating right in the module. I also have a new pick up coil to put in. It was only 7 bucks so whats the harm.

I am going to check the injector wires with a test light tonight. I will let everyone know how it goes.