engine help!
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
Likes: 0
I may not be following exactly what's happening, but:
"something weird happened. I turned the car on after all this and let it warm up then all of a sudden it just shut off it wouldn't fire but would crank....so I tried starting it again and it ran fine"
switch is normally "open" when engine not running.
When ignition key is in "start" switch is bypassed and power is fed to fuel pump relay.
This explains (at least one possible explanation) why your engine starts and runs with 0 psi
when ignition switch is turned back from "start" to "on", the ignition circuit no longer feeds power to the fuel pump relay.
switch is normally "closed" when engine running. when engine starts and oil pressure builds, switch closes and provides power to fuel pump relay.
If that switch is failing to close intermittently, or visa versa, goes open ...as in bad contacts or a bad diaphragm...it could go a long way in explaining your symptoms. In my experience, switches, especially pressure operated switches, fail intermittently over time, not catastrophically, all at once.
"something weird happened. I turned the car on after all this and let it warm up then all of a sudden it just shut off it wouldn't fire but would crank....so I tried starting it again and it ran fine"
switch is normally "open" when engine not running.
When ignition key is in "start" switch is bypassed and power is fed to fuel pump relay.
This explains (at least one possible explanation) why your engine starts and runs with 0 psi
when ignition switch is turned back from "start" to "on", the ignition circuit no longer feeds power to the fuel pump relay.
switch is normally "closed" when engine running. when engine starts and oil pressure builds, switch closes and provides power to fuel pump relay.
If that switch is failing to close intermittently, or visa versa, goes open ...as in bad contacts or a bad diaphragm...it could go a long way in explaining your symptoms. In my experience, switches, especially pressure operated switches, fail intermittently over time, not catastrophically, all at once.
I did a test and when I can get it running if I tap ontop of the ECM sometimes the fans will shut on and off and if it’s key on power and if I tap on it I can hear the switches turning off and on. And when it’s running if I tap on it sometimes it will shut off sooooo new ECM
Team Owner
Joined: Jul 2004
Posts: 28,426
Likes: 3,277
From: Hartford WI
I did a test and when I can get it running if I tap ontop of the ECM sometimes the fans will shut on and off and if it’s key on power and if I tap on it I can hear the switches turning off and on. And when it’s running if I tap on it sometimes it will shut off sooooo new ECM
Thread Starter
Intermediate
Joined: Jan 2018
Posts: 48
Likes: 0
Iv gone through every ground and what not . I don’t but the company iv been looking at told me if it doesn’t work I can return it. Should I look at a repair place or just go for a new one? It’s half the price for a repair
Team Owner
Joined: Jul 2004
Posts: 28,426
Likes: 3,277
From: Hartford WI
If they have gone through it, it might not be a bad idea to try.
