Today while driving home from work my 88 RS Camaro (305 Auto) shut off while driving. I had driven it to work and home for lunch with no issues whatsoever. On my way home I was coming out of a turn at a light and I had been accelerating up to 40mph and as soon as I hit about 35 the engine quit on me. I checked all the fuses under the dash first to make sure nothing had blown. I have since put in a new fuel filter and double checked that the fuel pump is pushing fuel out of the tank. I know that my fuel pump is running and I am pretty sure I have spark since if I put a little ether into the throttle body the engine fires once or twice. What could be going on here? I know there are some collision sensors that can cause the engine to not run but dont those stop the fuel filter? My check engine light has been on since I got the car and has never cause me any issues. I am going to check what codes it is throwing tomorrow to see if that can shed any light on this issue. I have the battery on a trickle charger since it was showing very low on the voltmeter on the dash. Anyone ever had an issue like this?

 

To answer one of your questions this happened to me one time while driving. Loose power cable to battery post. So my recommendation which you are checking already is battery and it’s connections. Need more info on start up though. Is it atleast turning over?

 

Yes sorry it is turning over. Everything inside looks normal except for I did notice that the parking brake light is coming on now when I turn the key. It is turning over as it should and priming the fuel system as it should. I will double check battery terminals but since it is turning over normally I would think that it is at least delivering power correctly. I am running the trickle charger to make sure it isnt too low voltage since it has always cranked a little slowly but it always started before. Is there any way to check if the fuel injectors are actually pushing fuel? Is there a relay or fuse that can fail and stop fuel from being delivered to the throttle body?

 

you can atleast ohm fuel injectors to see what resistance is there. Fuses would be under dash which you checked. Since it’s starting with fuel sprayed you’d have to start there.

 

Well it isnt like "running" when I am putting some gas in its just firing one or two times. I am going to pull a couple of the spark plugs to confirm I actually do have good spark and it isnt just autoigniting because Im putting in enough fuel. I will read the codes tonight and see if they can tell me anything more. Is there anything connected to the CEL that would cause the car to just shut off like mine did? I thought on OBD1 cars the CEL was mostly connected to nonessential sensors and emissions stuff.

 

The CEL is connected to the ECM (computer), which RUNS THE ENGINE. With TBI it is in total control. Most importantly, the ECM is what tells the injectors to inject, by pulsing them.

Sounds to me like you don't have a good reference pulse from the distributor. The behavior you describe is typical for that failure. Pretty common failure mode on TBI motors in general.

Best thing to do is probably to replace the distributor. The whole thing. Don't try to futz around with modules, pickup coils, etc. even though it's likely that some one part is bad, and you could in theory find that one part and "fix" it. Problem is, the dist has however many million miles on it, and is mechanically wore out, as well as whatever electric part has failed; even if you find and replace just the "failed" part, you still have a wore-out old sloppy dist that has a million miles on it.

Get one of the better quality rebuilds, at the least; not the cheeeeeeeeeepest "new" chinesium POS you can find on ebay. Should cost in the $75 - 100 neighborhood. Your local parts store or places like rockauto or maybe Summit etc. would be good places to look. NOT ebay. Likewise, you don't need a MSD or other high-$$$ "racing" one, it will make NO DIFFERENCE WHATSOEVER to how your car runs.

 

Ok Is there any way to diagnose if it is the distributor or not for sure? I found a few on rockauto in the $70 range. Is replacing the distributor a pull and plug replacement or do I need to do any timing or relearning after it is replaced?

EDIT: would it be worth it to try to just replace cap and rotor first? I am swapping an LT1 into this car at the beginning of next year so I just need to have it driveable until I get the LT1 ready to go in.

 

Also update: Trickle charger was on the car all night. Went to try to see if it would start up this morning. Still no start but definitely cranked better. Going to get codes today after work.

 

Just replace the ICM and get on with it.
Most likely the problem.

 

I talked to a SBC expert co-worker and he suggested replacing the fuel pressure regulator. That could explain my fuel flow but not having injection if the fuel is not pressurizing enough for the injectors to push it out. As far as I know the FPR has never been replaced. I suppose it could also be the Cam/Crank sensors but I would think the engine would still at least run without those just not very efficiently. I wouldnt think it is the ICM since I do have spark but I suppose I could have weak or misstimed spark. Again I am 100% certain that the fuel pump IS running I am just not sure if the pressure is building. At this point the plan is to pressure check the inlet into the throttle body to see if the fuel pump is building pressure and if it is not I am going to replace or rebuild the FPR. Luckily for me it is really easy to get to on TBI engines.

Underneath circled in red, that vaccum line was disconnected, not sure if it was part of the problem but I reconnected it to be sure, no change after reconnecting it.



FPR location for those interested, its the bronzeish part right behind the injectors:

 

Problem is not the regulator, if it won't run normally by pouring some gas in it.

Might be the ICM. As said however, you can replace that, which might or might not fix it; but even if it does, you still have a distributor with about a million miles on it. Just replace it and be done with it.

 

Good call

 

I would think a failing distributor would cause symptoms before failing entirely. I can troubleshoot if the fuel pressure regulator is the issue just by checking if it is building pressure or by plugging off the return line and seeing if it builds pressure that way. I would think that is WAY easier than "just replacing the distributor". I'm not a fan of just throwing parts and money at something until it fixes the issue, I have the time and access to the knowledge to troubleshoot the issue and find and fix the root cause. I would rather buy a $20 pressure regulator rebuild kit than a $70 distributor and then a $20 regulator rebuild kit after "just" replacing the distributor doesn't fix the issue...

 

Any way to troubleshoot the ICM?

 

Just went and checked the car out. It is throwing code 23 (intake air temp reading low) and code 32 (egr/map sensor malfunction) neither of which should cause the issue I am experiencing or the engine to not run at all. I did notice now that it does one single spritz of fuel after cranking for about 5-8 seconds as soon as I stop cranking but does not spray at all while cranking only once let off. I unhooked the fuel-in hose on the throttle body to verify fuel was being pushed to that point and it was, I also unhooked the fuel-out hose as well to see if any fuel sprayed out of the throttle body while cranking and I did not have any come out however it did seem that the gas tank was pushing fuel up that return line which I am not sure is supposed to happen. So as of right now to me it seems something that is supposed to be telling the injectors to pulse during cranking is malfunctioning until I can verify what my fuel pressure actually is and rule out a weak fuel pump. But I would think that even a weak fuel pump would allow the engine to start and idle.

 

Buy a noid light, and fuel pressure gauge.

 

Listen closely. Repeat after me.

If you can pour gas into the intake and it still doesn't fire, your problem IS NOT the fuel system. NOT NOT NOT NOT NOT NOT.

Are we clear on this point yet? THIS IS HOW WE SEPARATE A FUEL PROBLEM FROM A SPARK PROBLEM. It's so eeeeeeezy it hurts to even try to imagine how it is not possible for some people to grasp it.

Odds at this point are about 99.999% that your problem is within the distributor. Without the pulses it provides to the ECM, you will have neither spark, NOR fuel injector action. The ECM will never have the faintest vaguest dimmest foggiest hint of a whiff of a glimpse of a clue that the engine is TURNING and consequently it will behave EXACTLY as if the engine is SITTING STILL.. IOW it will do ABSOLUTELY NOTHING WHATSOEVER, including pulsing the injectors.

You can change out the ICM (aka ignition module, which is part of & inside of the distributor) if you want. I'd guess, if I were the guessing kind, that it's about 60% odds that that's what's broke. HOWEVER: replacement ICMs are not widely respected for reliability; and inadequate use of the heat sink compound GUARANTEES future failures. And even if you surmount those obstacles, you will STILL be left with an old wore out wobbly floppy dist with about a million miles on it, which even if it "works", will NOT give you "like new" performance.

Bust out the parts cannon. Shoot a distributor at your car.

 

^agreed not pointing at fuel now, however atleast with tpi, I’m pretty sure when the map sensor is disconnected the car will not start. Any tbi knowledge to share since he’s getting map and iat errors?

 

After further investigation last night I have determined that in addition to not pumping fuel while cranking I am also not getting spark. What I thought was "firing" must have just been the intake huffing the ether in. When I poured some fuel onto the throttle plates I had absolutely no firing or running so after that I checked for spark. I will be replacing distributor cap and rotor as well as coil and if those do not fix this issue I will look into replacing the ICM.

 

If you're going to throw parts at it....
ICM first then the rest if you want. It's the least cost.

 

Is the ICM underneath the cap and rotor on this engine? If so I will just go ahead and order one and do all of it at the same time I guess. Cap and rotor with distributor pickup and coil all together were only $50 so I can shell out another $40-50 for a new ICM

 

Yes it is.and don't forget the paste under it, it won't live if you do.

 

Its just thermal paste right? Like for a computer CPU? Should I be able to get some at autozone?

 

Nevermind it looks like the one I ordered comes with thermal paste

 

Every time I've seen a it shut off like I turned off the key it has been the ICM, fuel delivery usually hesitates some before it dies. One "free" check to do is with the cap off crank over the engine and make sure the rotor is turning to make sure there isn't a mechanical issue with the distributor. Everything else for me at least has had some sort of hiccup/hesitation before the car completely dies

 

If the bushings & cam gear are worn in distrubutor then...

 

Yes, I did see one that sheered the pin but that is rare.
9 out of 10 will be the ICM

It did happen to me recently and to my neightor last week.(ICM that is)

 

Well I found out what my issue was... I think the magnet at the top of the pickup pole disintegrated. A bunch of magnetic chunks fell out when I pulled the distributor cap off and the pickup coil is destroyed and the cover that is supposed to be over the pickup coil rotor is also all messed up. Can I just replace the pickup pole? how does that come out? Or should I just replace the whole distributor at this point? I will have to do timing and if I replace the distributor wont I?

 

Ok I did some research and it looks like at this point I might as well just get a new distributor. Is there a difference between a distributor that says its 'electronic' and one that is listed as 'pick up coil'? Will either work in my car? Are they both the same?

 

Oh my... yes, you need a new distributor. That thing look terrible. I recommend the Cardone or the Spectra Premium from Rockauto. They are cheap and both work fine in my cars.

 

*shaking my head*

 

If you never went to the dizzy you wouldn't have found the problem.
I too, had one like that and it still ran.
When I remove the dizzy it fell apart too.

 

Forgot to mention, I don’t think I’ve ever had a scenario where sofa was incorrect. Thanks for the knowledge and Info!

 

Ok so when I replace the whole thing I know I have to put the new one in the same position the old one comes out. What is the best way to make sure it goes in correctly? Should I put the rotor back on and put something straight on it and make a mark somewhere in the engine bay to line up with? Do I absolutely need to turn the engine until #1 is at TDC or do I just need to put it back in the same position?

I have a timing light I can borrow from a buddy and I have a good idea of how to do the timing as it isn't super difficult to do. But when I do the timing should I have the air cleaner installed so my airflow is correct or can I do it without the air cleaner?

 

You were 100% right my man. If I wasn't new I would have known to listen. Now I know!

 

Just put it back in the same position. Note the bottom of the dist gear the notch and turn it the same way - its for the oil pump and the dist wont seat without that being right, too.

Once its ballparked fire it up and time it.

 

Yup, put it in where it sits.

Be aware that the shaft turns about 30 degrees or so, CCW, as you pull it out. Do the whole job with the rotor on, and note where it turns itself to as you pull it.

The good thing about the Interwebz is, you get to profit from everybody else's mistakes and school of hard knocks, without having to make them yourself.