Ram From Hell
Full Access Member
I'm hoping to get some further ideas on where to look for a solution to this issue:
Truck was running fine after having the tune checked and tweaked where it had originally been built and tuned. It started to run a bit rough out of the blue one day, and stayed that way. I noticed at the time that an issue that the former owner had said was intermittent was now pretty much constant:
One bank was a point or more (sometimes as much as 2.5 more) lean that the other at idle and low RPM under load or not (i.e. operating on closed loop). Going into open loop, the AFRs are nearly identical.
On inspection, three plugs were found to have missing ground electrodes, presumably through detonation (All were replaced, of course.)
Since this was found:
Replaced all four O2 sensors (It had been run at high altitude where the tune was pig rich due to the low air density, and they were all badly sooted.) to ensure proper readings.
Had the injectors (Injector Dynamics 1000cc) rebuilt and flow-matched. All are now within 1.5%.
Pulled the intake, carefully examined for leaks, cleaned and resealed it with new gaskets, and personally torqued every bolt to spec in the proper order.
The truck is actually running a bit better, however this (presumed) closed loop lean bank issue persists. About all that I can think of now is that there is an issue with the ECU (AEM) or that somehow that tune has become corrupted.
Any other thoughts or suggestions?
Truck was running fine after having the tune checked and tweaked where it had originally been built and tuned. It started to run a bit rough out of the blue one day, and stayed that way. I noticed at the time that an issue that the former owner had said was intermittent was now pretty much constant:
One bank was a point or more (sometimes as much as 2.5 more) lean that the other at idle and low RPM under load or not (i.e. operating on closed loop). Going into open loop, the AFRs are nearly identical.
On inspection, three plugs were found to have missing ground electrodes, presumably through detonation (All were replaced, of course.)
Since this was found:
Replaced all four O2 sensors (It had been run at high altitude where the tune was pig rich due to the low air density, and they were all badly sooted.) to ensure proper readings.
Had the injectors (Injector Dynamics 1000cc) rebuilt and flow-matched. All are now within 1.5%.
Pulled the intake, carefully examined for leaks, cleaned and resealed it with new gaskets, and personally torqued every bolt to spec in the proper order.
The truck is actually running a bit better, however this (presumed) closed loop lean bank issue persists. About all that I can think of now is that there is an issue with the ECU (AEM) or that somehow that tune has become corrupted.
Any other thoughts or suggestions?
