Won't stay running
Thread Starter
Teching In
Joined: Sep 2012
Posts: 29
Likes: 0
Won't stay running 2004 LQ4 with a flashed PCM and stand alone harness. The engine cranks, and fires off quickly. It will run for a few seconds, and die. My tuner says VATS has been shut off.
We've confirmed the following:
-Fuel pressure at rail 58psi
-Scangauge reads voltage, air intake temp, water temp, engine RPM, ignition timing during crank and the first few seconds until it dies
-No codes found
-Engine will not continue to run even when carb start is used
-Getting spark at the plug during crank and first few seconds until it dies
-CEL is working during run/crank key positions
The factory oil pressure sensor is NOT plugged in or being used. I was told the PCM does not care about this signal.
Engine still dies with one of the following disconnected (one at a time)
-O2
-MAF
-Coolant Temp
-MAP
What do you guys think? I really feel like the PCM is shutting it down for some reason.
We've confirmed the following:
-Fuel pressure at rail 58psi
-Scangauge reads voltage, air intake temp, water temp, engine RPM, ignition timing during crank and the first few seconds until it dies
-No codes found
-Engine will not continue to run even when carb start is used
-Getting spark at the plug during crank and first few seconds until it dies
-CEL is working during run/crank key positions
The factory oil pressure sensor is NOT plugged in or being used. I was told the PCM does not care about this signal.
Engine still dies with one of the following disconnected (one at a time)
-O2
-MAF
-Coolant Temp
-MAP
What do you guys think? I really feel like the PCM is shutting it down for some reason.
Here's a good reference thread ...
https://ls1tech.com/forums/conversio...mediately.html
You can skip to post #44, if you want.
Post #10
https://ls1tech.com/forums/conversio...tup-issue.html
https://ls1tech.com/forums/conversio...mediately.html
You can skip to post #44, if you want.
Post #10
https://ls1tech.com/forums/conversio...tup-issue.html
Last edited by gMAG; Oct 14, 2012 at 10:12 PM.
Thread Starter
Teching In
Joined: Sep 2012
Posts: 29
Likes: 0
Here's a good reference thread ...
https://ls1tech.com/forums/conversio...mediately.html
You can skip to post #44, if you want.
https://ls1tech.com/forums/conversio...mediately.html
You can skip to post #44, if you want.
Trending Topics
Sounds like the vats delete did not take, and the oil pressure switch has nothing to do with your problem, the PCM does not need to see anything from the oil pressure switch. If you can find someone local with HP Tuners they can verify or try the vats delete.
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Teching In
Joined: Jan 2008
Posts: 1
Likes: 0
I wish I could give you definite info, but sometimes these issues will run you around in circles until it's resolved.
It may be as simple as turning VATS on & off once again.
Thread Starter
Teching In
Joined: Sep 2012
Posts: 29
Likes: 0
We got it running tonight! Not sure why, but it took some carb start into the intake to get it running, but it eventually found an idle and ran unassisted. The MAF is still suspect, but at least it runs.
2004 LQ4 with a flashed PCM and stand alone harness. The engine cranks, and fires off quickly. It will run for a few seconds, and die. My tuner says VATS has been shut off.
We've confirmed the following:
-Fuel pressure at rail 58psi
-Scangauge reads voltage, air intake temp, water temp, engine RPM, ignition timing during crank and the first few seconds until it dies
-No codes found
-Engine will not continue to run even when carb start is used-Getting spark at the plug during crank and first few seconds until it dies
-CEL is working during run/crank key positions
The factory oil pressure sensor is NOT plugged in or being used. I was told the PCM does not care about this signal.
Engine still dies with one of the following disconnected (one at a time)
-O2
-MAF
-Coolant Temp
-MAP
What do you guys think? I really feel like the PCM is shutting it down for some reason.
We've confirmed the following:
-Fuel pressure at rail 58psi
-Scangauge reads voltage, air intake temp, water temp, engine RPM, ignition timing during crank and the first few seconds until it dies
-No codes found
-Engine will not continue to run even when carb start is used-Getting spark at the plug during crank and first few seconds until it dies
-CEL is working during run/crank key positions
The factory oil pressure sensor is NOT plugged in or being used. I was told the PCM does not care about this signal.
Engine still dies with one of the following disconnected (one at a time)
-O2
-MAF
-Coolant Temp
-MAP
What do you guys think? I really feel like the PCM is shutting it down for some reason.
