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I’m new to owning a corvette but I have some experience working on Chevy and ford trucks. I just picked up an 85 corvette with an automatic Trans and I drove it home 45 minutes it seemed to run good enough (a little rough at times) but it got me home. I drove it for 2 days and I noticed it hesitating while giving it throttle while turning the wheel. Then it started stalling out when after making a turn, I got it home and checked the codes the only code was a code 43 which I believe to be a faulty knock sensor. Indeed The knock sensor pigtail connection is burned off, but now the car won’t start. I checked spark at every plug and the fuel rails have fuel pressure I am thinking it could be injectors but am not sure where to start.
Ok let's take a step back, spark seen felt confirmed. Fuel pressure how? Fingernail test Yah it bubbles? Or we have 35psi. Do you have injector pulse (are the injectors being told too, to be fire) a Noid light is need available at loan a tool part of big parts store or owning from Amazon or other sources.
This is a thing that do when I have a Corvette that won't start With pressure With spark With pulse is I pull a Fuel Sample how many times I have found water, enough times to look for it.
Last edited by s carter; Jan 21, 2023 at 11:01 AM.
Ok let's take a step back, spark seen felt confirmed. Fuel pressure how? Fingernail test Yah it bubbles? Or we have 35psi. Do you have injector pulse (are the injectors being told too, to be fire) a Noid light is need available at loan a tool part of big parts store or owning from Amazon or other sources.
This is a thing that do when I have a Corvette that won't start With pressure With spark With pulse is I pull a Fuel Sample how many times I have found water, enough times to look for it.
I took the plugs out and grounded them and saw spark in every one, I did not use a fuel pressure gauge just a finger nail test, and I did not check if the injectors were pulsing but when looking at my spark plugs it looks like fuel was only burnt on one side.
I have an 85 manual trans. After 20 trouble-free years of ownership, it died while idling in the smog-test bay. Had never died ever. It restarted, but wasn't normal. I began to drive it home, and every time I shoved the clutch in to shift it would die, I'd shift and let the clutch out and it would run again. I diverted to the parts house, bought a fuel pump, went home and installed it. That was 17 years ago, and it has never died while idling since. It was the fuel pump, and your symptoms are similar to mine. And both 85s which run lower fuel pressure than later year L98s.
Buy a fuel pressure gauge. You can't diagnose a Port Fuel Injected car without having one available. These engines won't start if the pump may pass the "push the valve, it spurts test" without producing adequate pressure.
it has a new fuel pump and sending unit but I didn’t install it so I don’t know if it was done correctly.
You really need to put your hands on the fuel pressure gauge, they are available for the day from most big parts stores Harbor freight even have them for not too much.
You really need to put your hands on the fuel pressure gauge, they are available for the day from most big parts stores Harbor freight even have them for not too much.
I’m about to go get one I’ll let y’all know when I check the pressure.
I got a fuel pressure tester and the rails read 35 psi. The car starts and drives now but it still wants to sputter out on turns while giving it throttle do y’all think that would be caused by the faulty knock sensor delaying the timing
From: Liliha Bakery stuffing my face with coco puffs!
Yeah, idk why aldldroid displays it in those increments. Haven't played with the program enough to determine if it can be tailored to my needs. Top row is in kPa which is what speed density uses. Not sure what the MAF cars would use...
From: Liliha Bakery stuffing my face with coco puffs!
If the integrity of the existing wire is still good, you could possibly depin the old connector and reinstall into a store replacement or just splice in the replacement. Knock sensor connector
the knock sensor isn't going to cause the engine to cut out the way you describe. How full is the gas tank? It's a known issue for these cars to have fuel starvation with less than a 1/4 tank on hard turns. My car had that issue at a half tank and less. There are things to try, like extra baffles, but what worked for me was either replacing the fuel pump or eliminating the pulsator. (IMO it was the pulsator, as it didn't feel very tight when I replaced the pump) The fuel puimp is easy to swap out, you can do it without removing or draining the tank.
the knock sensor isn't going to cause the engine to cut out the way you describe. How full is the gas tank? It's a known issue for these cars to have fuel starvation with less than a 1/4 tank on hard turns. My car had that issue at a half tank and less. There are things to try, like extra baffles, but what worked for me was either replacing the fuel pump or eliminating the pulsator. (IMO it was the pulsator, as it didn't feel very tight when I replaced the pump) The fuel puimp is easy to swap out, you can do it without removing or draining the tank.
it has a new fuel pump but I’ll fill it up with gas tomorrow and let you know tomorrow
Do y’all think a vacuum leak could be causing this since it seems to only happen when maxing out the steering? I filled it up with fuel and checked the pump and there’s no pulsator on the new pump, so I dont think that could be causing issues.
85 corvette won’t start
