1985 won’t turn over when hot
Thread Starter
Heel & Toe
Joined: Jul 2020
Posts: 19
Likes: 9
From: Staunton VA
1985 won’t turn over when hot
Hi everybody,
I’m having some trouble with my 85 C4. It won’t turn over when hot. It starts fine cold, but after sitting for a bit heat soak will get the coolant temp sensor up to about 200-220 and it won’t even crank - not until the coolant temperature drops to about 170-180ish.
I just recently replaced my starter and battery. Connections to the battery terminals should be good. I’ve done a lot of work to this car, I’m not sure how much of it is relevant to this problem but if you think of anything I’d be happy to share. Is there some sort of over temp switch that prevents you from starting?
im currently sitting at the Shell station gas pump with my hood open writing this post while the car cools back down, haha. I’d like to be able to get this problem fixed soon - thanks in advance for the help!
I’m having some trouble with my 85 C4. It won’t turn over when hot. It starts fine cold, but after sitting for a bit heat soak will get the coolant temp sensor up to about 200-220 and it won’t even crank - not until the coolant temperature drops to about 170-180ish.
I just recently replaced my starter and battery. Connections to the battery terminals should be good. I’ve done a lot of work to this car, I’m not sure how much of it is relevant to this problem but if you think of anything I’d be happy to share. Is there some sort of over temp switch that prevents you from starting?
im currently sitting at the Shell station gas pump with my hood open writing this post while the car cools back down, haha. I’d like to be able to get this problem fixed soon - thanks in advance for the help!
Thread Starter
Heel & Toe
Joined: Jul 2020
Posts: 19
Likes: 9
From: Staunton VA
I bought an adjustable FPR and set it to factory pressure, and the pump will run once the car starts… I guess I should clarify, when I say “won’t turn over” I mean it won’t even crank. The dash lights dim so I know something is pulling current, but the starter doesn’t turn.
Racer
Joined: Mar 2020
Posts: 387
Likes: 148
From: Langton, Ontario, Canada
2025 C4 of the Year Finalist - Unmodified
I had the same problem last time I overheated my 85. I let it cool down and everything went back to normal. I couldn't explain it and it never happened since. Good to know it's not just my car.
Last edited by LiveWire1; Jul 10, 2021 at 04:49 PM.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
If the dash goes blank, its probably the ground. If you already replaced the batt and starter, and it won't do anything when you turn the key, its the cables.
Thread Starter
Heel & Toe
Joined: Jul 2020
Posts: 19
Likes: 9
From: Staunton VA
It doesn't go blank, it just dims because the starter (I presume) is pulling current when I try to start it. Would the cables be the issue if the car still starts and runs normally at lower temperatures? I don't see that being a heat related issue, I guess...
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
It shouldnt be heat related, but thats all there is. The starter pulls current but if its not enough current or there isn't a good ground, it may not spin up. If its not spinning up at all, it has to be the cables or a bad ground.
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Pro
Joined: Dec 2018
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From: Wisconsin
2023 Corvette of the Year Finalist - Modified
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Is it stock or does it have long tube headers? If it has long tubes and the factory size starter I would suggest changing to a gear reduction starter like the later cars have. You get more clearance and they are more resistant to heat soak.
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Hi everybody,
I’m having some trouble with my 85 C4. It won’t turn over when hot. It starts fine cold, but after sitting for a bit heat soak will get the coolant temp sensor up to about 200-220 and it won’t even crank - not until the coolant temperature drops to about 170-180ish.
I just recently replaced my starter and battery. Connections to the battery terminals should be good. I’ve done a lot of work to this car, I’m not sure how much of it is relevant to this problem but if you think of anything I’d be happy to share. Is there some sort of over temp switch that prevents you from starting?
im currently sitting at the Shell station gas pump with my hood open writing this post while the car cools back down, haha. I’d like to be able to get this problem fixed soon - thanks in advance for the help!
I’m having some trouble with my 85 C4. It won’t turn over when hot. It starts fine cold, but after sitting for a bit heat soak will get the coolant temp sensor up to about 200-220 and it won’t even crank - not until the coolant temperature drops to about 170-180ish.
I just recently replaced my starter and battery. Connections to the battery terminals should be good. I’ve done a lot of work to this car, I’m not sure how much of it is relevant to this problem but if you think of anything I’d be happy to share. Is there some sort of over temp switch that prevents you from starting?
im currently sitting at the Shell station gas pump with my hood open writing this post while the car cools back down, haha. I’d like to be able to get this problem fixed soon - thanks in advance for the help!