C3 LS1 Swap - problems
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Teching In
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C3 LS1 Swap - problems Aloha everyone!
My setup:
Gen III LS1 from an ‘01 Camaro Z28 with 4L60E
Holley Terminator Max X
BTR Stage 2 cam
We just completed the swap into my ‘82 Corvette. Everything seemed to be going well. Nothing was leaking and fuel pressure was upwards of 50 psi; however, there was a once in a while backfire as throttle increased.
I was going through the learning process as Holley recommends. I took the car for a short two block drive: maybe 2/10 of a mile. I doubt I ever got the tac above 2,500. I did this for several days and on the second day of similar driving, just as I was pulling the car into my garage, I noticed the fuel pressure start to drop until the point where it was going to die, so I turned off the ignition and let it sit overnight,
The next day, the car either wouldn’t start or would start but really struggle to idle for a few seconds before it died. Again it did backfire from what sounded like the engine and the rear exhaust. Also, the last time I tried to start it, white smoke came from the exhaust and also the air intake. It wasn’t smoking prior.
I know white smoke is usually a sign of a head gasket, but I’m hoping for better news.
Does anyone have any ideas? Thanks I’m advance,.
My setup:
Gen III LS1 from an ‘01 Camaro Z28 with 4L60E
Holley Terminator Max X
BTR Stage 2 cam
We just completed the swap into my ‘82 Corvette. Everything seemed to be going well. Nothing was leaking and fuel pressure was upwards of 50 psi; however, there was a once in a while backfire as throttle increased.
I was going through the learning process as Holley recommends. I took the car for a short two block drive: maybe 2/10 of a mile. I doubt I ever got the tac above 2,500. I did this for several days and on the second day of similar driving, just as I was pulling the car into my garage, I noticed the fuel pressure start to drop until the point where it was going to die, so I turned off the ignition and let it sit overnight,
The next day, the car either wouldn’t start or would start but really struggle to idle for a few seconds before it died. Again it did backfire from what sounded like the engine and the rear exhaust. Also, the last time I tried to start it, white smoke came from the exhaust and also the air intake. It wasn’t smoking prior.
I know white smoke is usually a sign of a head gasket, but I’m hoping for better news.
Does anyone have any ideas? Thanks I’m advance,.
Thread Starter
Teching In
Joined: Jun 2022
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I can get it over 50psi with several primes so I don’t think that’s it. I’m curious why it’d smoke from the rear exhaust and intake. It feels like it has to be a problem in or around the intake but I think I’m over my head
TECH Apprentice
Joined: Aug 2018
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Do you know any history on the engine?
Make sure you don't have a leaky injector if the fuel pressure drops. A leaky injector can cause excess fuel after vehicle is shut down and hard starts on start-up the next day because it's partially flooded.
Diagnose FPR too.
Make sure you don't have a leaky injector if the fuel pressure drops. A leaky injector can cause excess fuel after vehicle is shut down and hard starts on start-up the next day because it's partially flooded.
Diagnose FPR too.
Thread Starter
Teching In
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Thanks for the responses.
I don't know the exact history of the engine. I know the car it came from, and there were no issues with the engine that I'm aware of.
Yes, I'll check if my injectors are leaking. I'm hoping it's the issue.
My FPR is in my tank. I'm using the Holley EFI Fuel pump (12-313), which also regulates the fuel. I have a new exhaust, so it won't be easy to drop the tank to remove my FPR. Any ideas how I can troubleshoot it in the tank?
I don't know the exact history of the engine. I know the car it came from, and there were no issues with the engine that I'm aware of.
Yes, I'll check if my injectors are leaking. I'm hoping it's the issue.
My FPR is in my tank. I'm using the Holley EFI Fuel pump (12-313), which also regulates the fuel. I have a new exhaust, so it won't be easy to drop the tank to remove my FPR. Any ideas how I can troubleshoot it in the tank?
Thread Starter
Teching In
Joined: Jun 2022
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Update:
I installed the new regulator and everything worked fine. I drove around for about a half mile and pulled it back into the garage. When I parked it, I noticed the fuel pressure dropping again. It wasn't like the last time when it smoked from both ends and backfired; it was only the fuel pressure. I'm guessing the regulator is going out again. Any ideas on what it could be or if it is the regulator, what would cause it to go out for a second time?
I installed the new regulator and everything worked fine. I drove around for about a half mile and pulled it back into the garage. When I parked it, I noticed the fuel pressure dropping again. It wasn't like the last time when it smoked from both ends and backfired; it was only the fuel pressure. I'm guessing the regulator is going out again. Any ideas on what it could be or if it is the regulator, what would cause it to go out for a second time?
