10.5Vette

Yesterday my 93 died on me and left me stranded. It stalled on me once while driving steady state, so I turned off the road and it fired right up. Drove it a little further, started hard, but started, drove it about 3 miles and it happened again. So I called my firend to go get my trailer and trailered it home. Did some checking while waiting for trailer to show up and had fuel, so I figured it was the opti.
Went to check codes today and the only thing it's throwing is code 32 EGR failure. I'm going to check more into the EGR when I get home from work, but it doesn't seem like the EGR failing would cause the car to die like that. I am still suspecting the opti (car has 85K on it, but PO put a new cap/rotor on it last summer).
Any thoughts? Could the EGR failing make the car die like that?
BY the way it starts and runs fine today, drove it in my driveway, don't dare take it on the road until I check a few things out.

NEVRL8T

jmrl98

When I had EGR problems, mine would almost die coming to a stop light, but then idle back up again. I have an L98, so it may be different.

bczee

The valve should remain closed while the engine is cold and at idle. It should only open once the engine has warmed up and is running at part-throttle. If the valve sticks shut (or is disconnected), NOX emissions will soar and detonation will often result. If it sticks in the open position or fails to close all the way, it acts like a vacuum leak resulting in a rough idle, hesitation and possible stalling.

Check to make sure it is functioing by using a hand vacuum pump. Should change the idle RPM as you operate it.

10.5Vette

I tried this and I cannot make the valve move with the pump. Won't build any pressure. Pump is okay, checked to make sure that wasn't the problem.
Still thinking there's another problem though, I don't think the EGR would kill the car while driving along.

bczee

Is the EGR valve stuck open ? can you operate the valve my sticking (wait till it is cold) your finger in through the bottom and lift the valve or even move it.. You should be able to.

If it is stuck in the open position. that will make your engine die like a giant vacuum leak.

10.5Vette

I'll go try that as soon as the motor cools. I just fired it up and it idles fine. As soon as I revved it say 35-4K it died, now it's back to not starting at all. Fuel pressure was perfect the whole time. I still have an inkling it may be the opti, or maybe the coils. Still searching....

BobRR3

You don't need a vacuum pump. Just hook a piece of hose on the EGR and suck on it. You should see the bladder move in and out. Also, If It's working, The engine will spudder when you pull the vacuum.

If the EGR has a leak it will affect the idle

10.5Vette

After it started and died (see earlier post) It will no longer start. But earlier today it idled fine, it was higher up rpm band when it would stall. However I checked egr valve and it will not move with finger pressure. So the valve is probably bad, but I don't think that's my stalling, not starting problem. Because when it does start it idles like normal. I'm kind of leaning towards opti or coil now. Wish it would show some codes though.

david350

The OPTI wont generate any codes. I had mine (1993 LT1 also) die in mid-ride @120k mi without warning, it was dead as a door nail though, never started back up. Way before the BS with the OPTI my odb was also throwing EGR codes, I drove it for 1+ years like that before I got around to R&R ing it, never stalled on me.

jngizzi

I just replaced the Opti on my '92 with 26K original miles. Correct: No codes were thrown.

My car didnt totally die. She ran a bit rough when cold. As soon as she heated up it sounded like it was going to die. As soon as the RPM's passed the 1650-1800 range she backfired like crazy, raw fuel smell, etc. etc.

After replacing opti, water pump, and wires she is running perfectly.

Cashmo

Original cat?

Jeff

10.5Vette

No Cat.

L71Maynard

My 92 has been dying the past couple of weeks after about 20 minutes of driving on warm days. I only get a code 62 in the 9.1 which is tach data error. Sometimes it starts back up in about 15-20 seconds and other times it takes up to 2 minutes. It really sucks when it happens at highway speeds because I never know if I'll coast fast enough to keep up with traffic and then pop the clutch and start it again. A couple of times it didn't fire back up and there was no break down lane so I screwed up the flow of traffic on the freeway because I had no where to go.

Last summer I was getting EGR codes but after I cleaned the EGR they went away.

Since there are occasions when the opti goes bad and doesn't throw a code, is there a way to test and see if the opti is causing this intermittent dying? Also the Service ASR light comes on and the tach will flicker and if you try to rev it the engine will sputter and misfire.


Dave

10.5Vette

No way I know of of testing the opti. Sounds like what my car was doing except with no clutch I couldn't restart it on the roll.
After serching on here and googling for an evening I "think" it's the ignition module, I've got a new one coming and I'm putting a new MSD coil on it as well. I had a 95 Trans Am with LT1 had a similar problem and it was the coil.
If all else fails I also have an MSD opti on it's way. Luckily I have a friend in the performance parts business and I got it at his cost, which was much much cheaper than advertised prices.
I'll keep you updated. Hopefully everything will be here by Saturday and I'll know during the weekend.

L71Maynard

Thanks for the reply. I was wondering about the ICM. I've got a delteq so my problem wouldn't be a coil since I have 4 of them. Hope that fixes your problem. I'll go look for an ICM.


Dave