94 keeps shutting off??
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From: Richfield Ohio
94 keeps shutting off??
94 LT1 has 37k miles, was running perfect, then after running 20 - 30 minutes it would start bucking popping under any throttle but very light, was able to get home, 2 weeks ago, it just shut off like I turned the key off, if I let it sit for 20 - 30 minutes it would run for about 20 seconds or so and shut off again. I checked fuel pressure, (car not running) just key on, 42 lb, after 10 minutes off it was still 40.5 lb. Wanted to do some tune up stuff, plugs wires done recently, changed O2 sensors, Knock sensors, EGR valve, flushed coolant, cleaned radiator, installed new thermostat, started ran for 20 minutes in the drive way, so I took it down the road just cruising 40 mph maybe, got less than 1/2 mile from home, shut off, towed it home, let sit for a couple of hours, hooked up fuel pressure gauge, turn on key right to 42 lb, started car, gauge dropped to somewhere between 35 - 38 lb while backing into garage car shut off again, when it shut off fuel pressure went right back to 42 lb, I'm kind of at a loss, can it be a fuel filter, fuel pump, or regulator, or do you think it's not fuel related? The OptiSpark is original, had a new cap installed in 2010, but only maybe 4k miles since then. Appreciate anyone's help.
Mark
Mark
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I would have you coil and icm tested. And hope it is not the opti. Have you washed the engine? And put a pressure gauge on it and tape it to the windshield and see what it does running. Be careful closing the hood not to crack your windshield. Also test for spark as soon as it dies.
Last edited by antfarmer2; Jun 10, 2016 at 09:10 PM.
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From: Richfield Ohio
Have not washed engine, and was exceptionally careful not to get any liquid around it. Even used a vacuum pump to suck all liquid out of thermostat housing before removing it. I did have the fuel gauge laying on windshield when backing into garage tonight, when it shut of the pressure raised back to 42 lb, while running it was between 35 - 38 lb. Not sure how to check Coil or ICM?
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Have not washed engine, and was exceptionally careful not to get any liquid around it. Even used a vacuum pump to suck all liquid out of thermostat housing before removing it. I did have the fuel gauge laying on windshield when backing into garage tonight, when it shut of the pressure raised back to 42 lb, while running it was between 35 - 38 lb. Not sure how to check Coil or ICM?
Last edited by antfarmer2; Jun 10, 2016 at 09:43 PM.
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From: Richfield Ohio
Installed the ICM tonight, yes I used thermal paste. Started right up, drove less than 1/2 mile shut off, let it sit 5 minutes or so, it started and I got it home, as I was pulling into the garage, it missed once and shut off. It's not turning on the check engine light, nor showing any codes, it turns off like you shut the key off. I'm kind of getting tired of it, I can't drive it anywhere. I am very good mechanically, but when I go through the service manual and it starts asking to check items, to me it's not clear what they want you to check or how to check it, I do have a Fluke meter that I've used a lot mostly on machines trouble shooting, not so much on cars.
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From: Richfield Ohio
Both of the parts store around me, couldn't check the coil, only one was able to check the ICM. I'm also hoping it's not the Opti.
The car only ran for maybe 1 - 2 minutes each time, don't think the coil could have even heated up that quick.
There is one thing I noticed today, last Saturday it ran in my driveway for almost 20 minutes, then when I started down the road to check it driving it shut off almost the exact same place on the road, as it shut off today, only today I just started it and pulled out right away and started down the road, like I said it was only running for between 1 - 2 minutes this time.
Is there something that operates only while driving and not while in park sitting in the driveway, that could shut the car off?
The car only ran for maybe 1 - 2 minutes each time, don't think the coil could have even heated up that quick.
There is one thing I noticed today, last Saturday it ran in my driveway for almost 20 minutes, then when I started down the road to check it driving it shut off almost the exact same place on the road, as it shut off today, only today I just started it and pulled out right away and started down the road, like I said it was only running for between 1 - 2 minutes this time.
Is there something that operates only while driving and not while in park sitting in the driveway, that could shut the car off?
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Try taping the fuel gauge to the windshield and see what it does when it dies. Careful closing the hood do not want to crack the windshield. Watch the digital volt meter too. Also try smacking the ECM while idling and see what it does. And strap a cold pack on it and see if it does better.
Last edited by antfarmer2; Jun 18, 2016 at 07:55 PM.
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From: Richfield Ohio
I've already done the fuel gauge on the windshield, no difference there it shut off with 35 - 38 pounds of fuel pressure.
Just came back in house, started it let it run in the garage for 20 minutes, digital temp was at 198° still running, got in a did some stepping on the throttle to see how it acted, if you give it gas slowly no issues, fast it would stumble a few times under 2k rpm's and then go right up. I'll have to try the ECM suggestions, that is it right above the battery correct?
Just came back in house, started it let it run in the garage for 20 minutes, digital temp was at 198° still running, got in a did some stepping on the throttle to see how it acted, if you give it gas slowly no issues, fast it would stumble a few times under 2k rpm's and then go right up. I'll have to try the ECM suggestions, that is it right above the battery correct?
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I've already done the fuel gauge on the windshield, no difference there it shut off with 35 - 38 pounds of fuel pressure.
Just came back in house, started it let it run in the garage for 20 minutes, digital temp was at 198° still running, got in a did some stepping on the throttle to see how it acted, if you give it gas slowly no issues, fast it would stumble a few times under 2k rpm's and then go right up. I'll have to try the ECM suggestions, that is it right above the battery correct?
Just came back in house, started it let it run in the garage for 20 minutes, digital temp was at 198° still running, got in a did some stepping on the throttle to see how it acted, if you give it gas slowly no issues, fast it would stumble a few times under 2k rpm's and then go right up. I'll have to try the ECM suggestions, that is it right above the battery correct?
Thread Starter
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Joined: Dec 2015
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From: Richfield Ohio
Just for a test I used a jumper to see if there were any stored codes in the computer, (my check engine light is not on) it does work comes on when you turn the key, goes right off when it starts. There are 5 codes and the first 2 really suck, 16 & 36 distributor low and hi pulse, 42 ignition control shorted, I changed this already, 62 oil temp sensor low voltage, 64 bank 2 O2 sensor circuit lean. The one thing I noticed today when I was getting codes, there is an air pump in front of LF tire, that keeps cycling on and off, does that mean anything? Never noticed that before.
Obviously I'm now in need of an Optispark, is there a way to test if I just need a cap and rotor before I spend $ on a new distributor? I believe the Opti in my car is original 1994 37k miles.
I unhooked the battery so all the codes will be erased, will it set codes quickly, if I get it to start tomorrow, only ran today for about 1 minute, chugged a couple of times and off it went.
Mark
Mark.
Obviously I'm now in need of an Optispark, is there a way to test if I just need a cap and rotor before I spend $ on a new distributor? I believe the Opti in my car is original 1994 37k miles.
I unhooked the battery so all the codes will be erased, will it set codes quickly, if I get it to start tomorrow, only ran today for about 1 minute, chugged a couple of times and off it went.
Mark
Mark.
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From: Richfield Ohio
posted pictures of Opti. I think it's the Opti.
https://www.corvetteforum.com/forums...i-removed.html
https://www.corvetteforum.com/forums...i-removed.html
Last edited by mat1227; Jun 28, 2016 at 11:58 AM.
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posted pictures of Opti. I think it's the Opti.
https://www.corvetteforum.com/forums...i-removed.html
https://www.corvetteforum.com/forums...i-removed.html
Thread Starter
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Joined: Dec 2015
Posts: 116
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From: Richfield Ohio
New Petris Opti installed, started instantly running perfect so far, only about 10 miles. I do like the idea that it's vented like the 95 - 96 original Opti's.
Through this experience it showed me just how bad of work the Chevy dealer did when they changed the Opti cap about 5 years ago. They didnot use any waterpump gaskets, only silicone, and it was smeared everywhere. They routed the plug wires horribly, some were against the studs of the exhaust manifolds, did not have any of the wire protectors on them any longer. Overall they do crap work. This is why I never let anyone work on my car if possible.
I replaced the plugs and wires, fuel filter, O2 sensors, knock sensors, EGR valve, oil change, flushed coolant, lower temp thermostat.
Mark
Through this experience it showed me just how bad of work the Chevy dealer did when they changed the Opti cap about 5 years ago. They didnot use any waterpump gaskets, only silicone, and it was smeared everywhere. They routed the plug wires horribly, some were against the studs of the exhaust manifolds, did not have any of the wire protectors on them any longer. Overall they do crap work. This is why I never let anyone work on my car if possible.
I replaced the plugs and wires, fuel filter, O2 sensors, knock sensors, EGR valve, oil change, flushed coolant, lower temp thermostat.
Mark