GAH! Broke down..Cranks but no start.
 

So, yesterday I went to get gas, car ran great, no problems at all. So I proceed to pull in the gas station, went in, paid for my gas and pumped it. Got back in the Bonne... crank crank crank crank...hmm uh oh...crank crank crank crank...SHIT!

So, I pull out my scantool, no codes...hmmm. Fuel pressure, perfect...hmm. So anyways I got it towed home, and this is when I found my grandma (see post in lounge), so today I want to diagnose it. So a few minutes ago, I checked the spark, and guess what? No spark! So guys, what can the problem be? I have no codes, fuel pressure is fine, but no spark whatsoever.

Urgh... :x

EDIT - yes, all fuses are good. I checked. ;)

Id say one of 3 things...

Crank Sensor

Ignition Control Module

Or Possible bad wire to one of the 2 above

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Seeins how you just messed with the frontend of the engine, I would guess your ICM harness.

Got a spare ICM laying around?

Isn't the 92 an adjustable crank sensor? Where the 93 is set it and forget it?

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Wouldn't hurt, you were gonna change it anyways ;-)

Crank sensor is fine, it was just replaced with a new ACDelco one. I have absolutely no codes also except for the normal 58.

I absolutely have no spark, so I am assuming a bad ICM, unfortunately I don't have the money at the time, so if anyone has a spare one, I'd like to borrow it to be absolutely certain it is my problem. I am not too happy because it just HAD to fail right before Sears will end up calling me in for my job training. :roll:

If anyone has one to sell me or borrow, PM me with a total price, or a price for shipping if I can borrow it.

Did you check the fuses on the passenger side? The ICM fuse is over there. If you have a voltmeter it's actually easier to just check for 12 volts (key on) at the pink wire going to the ICM.
If the crank sensor was rubbing on the harmonic balancer it wouldn't last long.

you sure you're getting pressure? Because I've had problems with the fuel pump fuse going out before...

All fuses are fine, never had a fuse blow so far. Fuel pressure is the norm. with the key on. Someone told me that the ICM could have failed due to lack of dielectric grease on the back. True? Just wondering because it's never had any grease on it.

BTW, the crank sensor is fine in terms of adjustment, I have friends in places (got to borrow a crank sensor tool from the dealer) 8)

Well, just to let you know, I've had to replace that fuse twice on that car ;-)

That was before all the grounds were cleaned up. ;)

As I said, I know it's a ICM problem, no spark whatsoever, my Dad even held the sparkplug against a ground, and didn't even give a weak spark off. :(

Hmm... well now I am clueless...

I am not sure how accurate the Wells ignition system tester is at AutoZone, but they tested it 5 times in a row, and passed everytime. SIGH.... :?

I guess I am going out there to check the fuses again, and see if I am getting 12v at the pink wire.

Hmmm......either the harness got pinched, or you lost ground to the ICM. Check to see if you get good ground from the ICM mount. I would also wirebrush it just to clean off some corrosion from it, and coat it with dilectric grease.

And though the fuse associated with it may be good, that doesn't mean the terminals AT the fuse is good. Take the fuse out, and see if you measure battery voltage at one terminal, and continuity with the other terminal and the 12 volt pin at the ICM.

I just went through dumping a bucket of parts for multiple symptoms. In reality, a bunch of it could be blamed on crapped out connectors in the powertrain control circuits.
One similar problem to yours, was caused by the large (black) 32 pin connector on the PCM (computer). It was a wallowed out female pin. I drove for weeks with the PCM laying on the floor so I could unplug/replug the connector or even just jiggle it; until I figured out how to find the loose pin and fix it. So don't rule out connections between the ICM, and PCM, which also are fed through the 8-way connector, physically near the #2 injector. Sometimes, just unplugging and replugging will TEMPORARILY fix the issue. Oh, on the other question of white grease on the back of the ICM. No, I have never seen any that use it... at least not from the factory.

The thing with the grease on the ICM.... I don't know why this has crossed to the 3800 as this is not the case... I have never seen a 3800 use the grease either..

But.... This is done on the Quad 4 Ignition control module and then the Module is bolted to the Cover plate...

But never heard of or seen this on a 3800

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Ok, checked the pink wire going to the ICM, and it has 12.10 volts.

All the PCM connections are good and solid.

Grounds are clean and are not broken.

I'm assuming you already checked the connection at the crank sensor.
Also assuming you checked for spark at more than one coil.

Try unplugging the cam sensor & see if it starts.
I'm 99.9 % sure that the ICM on 92s ground through the ICM mounting bracket. Remove the ICM & mounting plate from the mounting bracket. Clean the top of mounting bracket, both sides of mounting plate & bottom of ICM. I coat all 4 surfaces with a light coat of dielectric grease to help prevent the corrosion from coming back.

If it still won't start your back to the crank sensor or the ICM wiring harness.

Oh yeah - also assuming you have a good & well charged battery.

Out of curiousity, because I thought the early Bonnies would crank but not start but I'm not sure, whats the Security Light doing when you try to start her?

ICM
 

First thing you gotta do is remove the ICM connector and look into the sockets. Most of them will be bent back too far. Get a tiny screwdriver in there and get behind them from side to side and bend them forward. Now put the connector on and off a couple of times, apply dielectric grease, then see if you have spark.

Did you get this resolved?

I got a spare ICM coming from whitecrystal1... I am gonna install it and see if it fixes it. I took the ICM up to Autozone again last night, and it FAILED the tests, yet a few days ago it passed. :roll: :evil:

That's been known to happen.

Yeah, and the funny thing is it was the same guy that tested it the other day. He actually said "Why do you want me to test it again? It passed."

I replied "Because these Wells machines are either unreliable, or are programmed to show pass/fail when it wants to." :lol:

New ICM is in...

















Still no start. :evil:

i am clueless......12.10v at the pink wire, grounds are ok, no codes, I am totally confused.

Check and see if you have injector pulse....

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Just checked all grounds, cleaned them a little bit more, no change.

And just checked injector pulse, and the bulb doesn't even light up at all. :x

Ok.... I believe that no spark and no fuel pulse may be grounds for replacing the Crank sensor..

Thoughts Guys?

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Did you clean the mounting plate, bracket & bottom of ICM?

If so then try unplugging the cam sensor. If that doesn't help then you should swap crank sensors. Do you still have the old sensor?

Mounting plate, bracket, and bottom of the ICM are all clean.

I'll unplug the cam sensor and see what it does... I am hoping it isn't the crank sensor, as it is a new ACDelco one... it was adjusted properly, so I know it didn't get eaten up, it ran for 4 days straight with no problems.

Unbelievable.........





I unplugged the cam sensor, reached in and cranked it.... IT STARTED! :shock:

So... What's the problem then? :?

Here's one more test you can try before changing the crank sensor. Connect the meter to the pink wire again & see how much the voltage is dropping while someone cranks over the engine.

Forget the last post - you sneaked in there with the good news. I think you need a new cam sensor but can't tell you that with 100% certainty.

SHIT... and I just replaced the cam sensor 2 months ago. I guess that's what I get for buying a Non-ACDelco sensor. :x

Ok..... well this is weird.... I let it run for about 10 minutes with the cam sensor unplugged. I turned it off and plugged the cam sensor back in, and it fired right up! No codes! I proceeded to wiggle the plug with my dad watching the dash and scantool, and no codes popped up! I guess I am gonna go drive it around the block and see what it does.

That's an interesting twist & very weird. You might want get an ICM wiring harness from a junkyard. Keep that & any tools needed to change it in the car for a while.

I swapped out my ICM harness a while back. I found 2 ill-fitting pins on the cam sensor connector and a few on the ICM connector. You can straighten out a standard size paper clip to use as a testing tool. Compare its fit in the various female pins. Pay close attention and look for one that fits looser that the others. Usually you will feel resistance almost immediately on a good pin. Just a thought.

Hey Will, when you drive it, keep an eye on your idle. I want to see if it fixed it ;-)

It idles silky smooth at 1000. :lol:

On the other hand, I drove it back and forth to wal-mart earlier, no CEL, no hiccups, started right up both times. I'm thinking it was a flaky connection at the cam sensor, or it was very possible the old ICM had problems that made something screw up. Who knows... :lol: All I know is it seems to idle much smoother with the new ICM... not lower, but smoother.

The cam sensor isn’t supposed to prevent the car from starting. From looking at wiring diagrams I always thought that if the cam sensor were to short out then it could prevent the crank signal from getting to the ICM & result in a no start condition. That’s why I wanted you to try unplugging it. It appears that you just got lucky by wiggling the wires and either fixed a poor connection or a short in the wiring. I’d remove the wiring harness, remove the conduit, clean all the wires & look for any cracks in the insulation. This is in addition to the checks RedSled recommended. Or as previously mentioned – carry a spare.