occasional problem starting, rough run
Thread Starter
Cruising
Joined: May 2018
Posts: 13
Likes: 0
From: New Braunfels Texas (TX)
occasional problem starting, rough run
I have a 1995 corvette that has all of a sudden come across a starting and running issue.
Just one day it was running fine, took it out for a bit, turned it off, but got back like 10 minutes later and it wouldn't start. After turning it over (more times than i should have) it started but was running extremely rough, sounded worse than a lawn mower.
After checking what i could, i saw there was oil around the valve cover at cylinder 6 and 8.
Since there was nothing i could do i left it to cool off (i guess). After some time, it had trouble starting again, but when it ran, it was fine.
When getting it back, it just died on the road, but started up again after a few minutes.
Then, after further inspection, i removed the valve covers to check the gasket, and there was a small abrasion about 3/4 inch long, enough for a slight oil leak.
im replacing the gasket just because, but i need some help here, dunno what to look into, etc (need to check plugs and wires, but that would cause the car to just die, right???)
Just one day it was running fine, took it out for a bit, turned it off, but got back like 10 minutes later and it wouldn't start. After turning it over (more times than i should have) it started but was running extremely rough, sounded worse than a lawn mower.
After checking what i could, i saw there was oil around the valve cover at cylinder 6 and 8.
Since there was nothing i could do i left it to cool off (i guess). After some time, it had trouble starting again, but when it ran, it was fine.
When getting it back, it just died on the road, but started up again after a few minutes.
Then, after further inspection, i removed the valve covers to check the gasket, and there was a small abrasion about 3/4 inch long, enough for a slight oil leak.
im replacing the gasket just because, but i need some help here, dunno what to look into, etc (need to check plugs and wires, but that would cause the car to just die, right???)
Drifting
Joined: Apr 2014
Posts: 1,699
Likes: 231
From: Hawthorne CA
I have a 1995 corvette that has all of a sudden come across a starting and running issue.
Just one day it was running fine, took it out for a bit, turned it off, but got back like 10 minutes later and it wouldn't start. After turning it over (more times than i should have) it started but was running extremely rough, sounded worse than a lawn mower.
After checking what i could, i saw there was oil around the valve cover at cylinder 6 and 8.
Since there was nothing i could do i left it to cool off (i guess). After some time, it had trouble starting again, but when it ran, it was fine.
When getting it back, it just died on the road, but started up again after a few minutes.
Then, after further inspection, i removed the valve covers to check the gasket, and there was a small abrasion about 3/4 inch long, enough for a slight oil leak.
im replacing the gasket just because, but i need some help here, dunno what to look into, etc (need to check plugs and wires, but that would cause the car to just die, right???)
Just one day it was running fine, took it out for a bit, turned it off, but got back like 10 minutes later and it wouldn't start. After turning it over (more times than i should have) it started but was running extremely rough, sounded worse than a lawn mower.
After checking what i could, i saw there was oil around the valve cover at cylinder 6 and 8.
Since there was nothing i could do i left it to cool off (i guess). After some time, it had trouble starting again, but when it ran, it was fine.
When getting it back, it just died on the road, but started up again after a few minutes.
Then, after further inspection, i removed the valve covers to check the gasket, and there was a small abrasion about 3/4 inch long, enough for a slight oil leak.
im replacing the gasket just because, but i need some help here, dunno what to look into, etc (need to check plugs and wires, but that would cause the car to just die, right???)
Any codes?
Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
Yes, check for codes first!
My thoughts would be to next verify fuel pressure (approx 40-41 psi for the LT1,4s).
From experience, my 95 had similar issues that turned out to be an O2 sensor intermittently failing. I had to put a scanner on it and take it for a drive to catch that one!
Anywayz... See what the codes tell ya first and get back. Don't be an idiot and start tossing parts at it!
My thoughts would be to next verify fuel pressure (approx 40-41 psi for the LT1,4s).
From experience, my 95 had similar issues that turned out to be an O2 sensor intermittently failing. I had to put a scanner on it and take it for a drive to catch that one!
Anywayz... See what the codes tell ya first and get back. Don't be an idiot and start tossing parts at it!
Pro
Joined: Oct 2004
Posts: 551
Likes: 23
From: Wills Point Texas
I hate to bring up the "opti" word up but that is exactly how mine was running. One day it was running just fine and came out one day and ready for a great Sunday drive and she wouldn't start. Just tuned over and over but not a sign of a startup.
Puzzled that just a day before she was running like a top! I went in to the house for a bit and I came back out about a few hours later and she started right up again and drove great.
I came out the next day or so and she wouldn't start again then thinking OK, I'll try the "going back in the house and coming back out later thing.....LOL" (hoping it was just a glitch)
OK, She started up but ran like pure crap. and this continued on and on.
I checked the fuel pressure first and all was good with no CEL at all.
Long story short changed the opti and she's now running like she's brand new and with both of us with a big smile just tooling down the road.
BTW this was a API opti with a two year warranty through Saccity Corvette. I had "0" problems at all with them on the warranty end with only one week left on the two year warranty. They shipped me one right out with no problems at all.
Puzzled that just a day before she was running like a top! I went in to the house for a bit and I came back out about a few hours later and she started right up again and drove great.
I came out the next day or so and she wouldn't start again then thinking OK, I'll try the "going back in the house and coming back out later thing.....LOL" (hoping it was just a glitch)
OK, She started up but ran like pure crap. and this continued on and on.
I checked the fuel pressure first and all was good with no CEL at all.
Long story short changed the opti and she's now running like she's brand new and with both of us with a big smile just tooling down the road.
BTW this was a API opti with a two year warranty through Saccity Corvette. I had "0" problems at all with them on the warranty end with only one week left on the two year warranty. They shipped me one right out with no problems at all.
Thread Starter
Cruising
Joined: May 2018
Posts: 13
Likes: 0
From: New Braunfels Texas (TX)
I hate to bring up the "opti" word up but that is exactly how mine was running. One day it was running just fine and came out one day and ready for a great Sunday drive and she wouldn't start. Just tuned over and over but not a sign of a startup.
Puzzled that just a day before she was running like a top! I went in to the house for a bit and I came back out about a few hours later and she started right up again and drove great.
I came out the next day or so and she wouldn't start again then thinking OK, I'll try the "going back in the house and coming back out later thing.....LOL" (hoping it was just a glitch)
OK, She started up but ran like pure crap. and this continued on and on.
I checked the fuel pressure first and all was good with no CEL at all.
Long story short changed the opti and she's now running like she's brand new and with both of us with a big smile just tooling down the road.
BTW this was a API opti with a two year warranty through Saccity Corvette. I had "0" problems at all with them on the warranty end with only one week left on the two year warranty. They shipped me one right out with no problems at all.
Puzzled that just a day before she was running like a top! I went in to the house for a bit and I came back out about a few hours later and she started right up again and drove great.
I came out the next day or so and she wouldn't start again then thinking OK, I'll try the "going back in the house and coming back out later thing.....LOL" (hoping it was just a glitch)
OK, She started up but ran like pure crap. and this continued on and on.
I checked the fuel pressure first and all was good with no CEL at all.
Long story short changed the opti and she's now running like she's brand new and with both of us with a big smile just tooling down the road.
BTW this was a API opti with a two year warranty through Saccity Corvette. I had "0" problems at all with them on the warranty end with only one week left on the two year warranty. They shipped me one right out with no problems at all.
Flatulent Dwarf
Joined: Nov 2009
Posts: 729
Likes: 84
From: Poverty Holler NC
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Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
My 95 LT1 coupe never gave me any trouble, opti-wise. But, as I read these C4 forums, that part gets a lot of attention.
So, I'm curious... Does anyone have data that shows opti failures by model year? I'd always heard the vented optis was the turning point, far as reliability goes. What say you experts? (I guess when I bought the Z I dodged that bullet, huh?)
.
Thread Starter
Cruising
Joined: May 2018
Posts: 13
Likes: 0
From: New Braunfels Texas (TX)
So, after some assistance from an LT friend, we think we found the problem at the coil and ignition control module. We changed them out with temporary testers, and the car ran fine for a while. Then it started dying again, but we never changed the ICM and coil together. Once we did it ran for a few days with no problems at all, then it started again yesterday when it was like 100 degrees outside. Now its throwing an H42 and H16. someone mentioned that combination is the death code, is that true?
PS- after the death code, i messed with the coil connectors because one is partially torn and im wondering if the problem is all starting with the bad connector. The wire is visible and it looks as if the wire itself is partially torn, thoughts?
Also, before i replaced the ICM and coil, it was only throwing H16, now its both.
PS- after the death code, i messed with the coil connectors because one is partially torn and im wondering if the problem is all starting with the bad connector. The wire is visible and it looks as if the wire itself is partially torn, thoughts?
Also, before i replaced the ICM and coil, it was only throwing H16, now its both.
Last edited by UssIowa; May 30, 2018 at 12:53 PM.
Pro
Joined: Oct 2004
Posts: 551
Likes: 23
From: Wills Point Texas
So, after some assistance from an LT friend, we think we found the problem at the coil and ignition control module. We changed them out with temporary testers, and the car ran fine for a while. Then it started dying again, but we never changed the ICM and coil together. Once we did it ran for a few days with no problems at all, then it started again yesterday when it was like 100 degrees outside. Now its throwing an H42 and H16. someone mentioned that combination is the death code, is that true?
PS- after the death code, i messed with the coil connectors because one is partially torn and im wondering if the problem is all starting with the bad connector. The wire is visible and it looks as if the wire itself is partially torn, thoughts?
Also, before i replaced the ICM and coil, it was only throwing H16, now its both.
PS- after the death code, i messed with the coil connectors because one is partially torn and im wondering if the problem is all starting with the bad connector. The wire is visible and it looks as if the wire itself is partially torn, thoughts?
Also, before i replaced the ICM and coil, it was only throwing H16, now its both.