Intermittent start fail
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Intermittent start fail Just rebuilt my 5.3 in my 2002 Tahoe, it’s stock other than an Elgin E-1256-P torque cam. I’m having a problem with it intermittently not starting on the first try. It doesn’t matter if it’s a hot or cold start. You can release the key and it’ll start up every time on the second try and run great. It’s not throwing any codes at all. I replaced all sensors during the build, I did however purchase aftermarket cam and crank (Echlin) sensors from Napa, might’ve been a mistake. I thought it was probably fuel related so I installed a new Delphi fuel pump and replaced the fuel pressure regulator as well, still doing it. I thought it might be the evap purge valve so I replaced it, still doing it. I thought it might just need to be tuned because of the cam swap so I had it custom tuned on a wheel dyno, still doing it. They put a fuel pressure gauge on it and it’s not losing fuel pressure so the fuel pump, regulator and injectors are not leaking. This thing runs strong, it put down 310hp and 342lbs of torque at the wheels even though it’s still got stock manifolds and single exhaust. The tuner said the cam and crank sensors appear to be working as they should. I pulled a spark plug wire and it’s getting fire during the start fail. I’m running out of ideas, need help. I thought about putting my old crank and cam sensors back in just to see if one of my aftermarket sensors might be bad. It’s got over 5000 miles on it, you would think it would’ve thrown a code by now. Any suggestions would be greatly appreciated!!
Thread Starter
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Joined: Oct 2021
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I was told that if the VATS was malfunctioning it would initially start up and then immediately go dead. Mine will either start right up first try or just spin over. If it doesn’t crank within a couple of revolutions you can release the key, I don’t mean turn the ignition off and back on, just release the key and hit it again and it’ll start right up every time without hesitation. 🤷♂️
Thread Starter
Registered User
Joined: Oct 2021
Posts: 3
Likes: 0
Just rebuilt my 5.3 in my 2002 Tahoe, it’s stock other than an Elgin E-1256-P torque cam. I’m having a problem with it intermittently not starting on the first try. It doesn’t matter if it’s a hot or cold start. You can release the key and it’ll start up every time on the second try and run great. It’s not throwing any codes at all. I replaced all sensors during the build, I did however purchase aftermarket cam and crank (Echlin) sensors from Napa, might’ve been a mistake. I thought it was probably fuel related so I installed a new Delphi fuel pump and replaced the fuel pressure regulator as well, still doing it. I thought it might be the evap purge valve so I replaced it, still doing it. I thought it might just need to be tuned because of the cam swap so I had it custom tuned on a wheel dyno, still doing it. They put a fuel pressure gauge on it and it’s not losing fuel pressure so the fuel pump, regulator and injectors are not leaking. This thing runs strong, it put down 310hp and 342lbs of torque at the wheels even though it’s still got stock manifolds and single exhaust. The tuner said the cam and crank sensors appear to be working as they should. I pulled a spark plug wire and it’s getting fire during the start fail. I’m running out of ideas, need help. I thought about putting my old crank and cam sensors back in just to see if one of my aftermarket sensors might be bad. It’s got over 5000 miles on it, you would think it would’ve thrown a code by now. Any suggestions would be greatly appreciated!!
