Remanufactured ECM
Administrator
Joined: Apr 2010
Posts: 87,396
Likes: 4,213
From: Clayton MI
I would wonder if it actually IS running lean, and the PCM is interpreting a lean-burn miss, as a failing coil....... It's a stretch, but, a possibility.
How old are the O2 sensors, if they have been replaced, what brand were the replacements?
I suppose an easy test would be to unplug the O2 sensor, clear all codes, and drive it for a while, and see what happens. If the problem doesn't come back, replace the sensors.
How old are the O2 sensors, if they have been replaced, what brand were the replacements?
I suppose an easy test would be to unplug the O2 sensor, clear all codes, and drive it for a while, and see what happens. If the problem doesn't come back, replace the sensors.
Professional
Joined: Jul 2019
Posts: 139
Likes: 5
From: Los Angeles
Just looked in my service manual and the coil packs run right from the PCM
the only vehicle that had a separate modual for spark was the early vipers. They had a VIC, viper ignition controller , it ran the coil packs and the last two fuel injectors. Funny thing is, the separate box used was a A604 trans controller box!! Lol. Engineers were saving money!!
well, code 43. Start with changing the coils packs, then start looking at wiring
the only vehicle that had a separate modual for spark was the early vipers. They had a VIC, viper ignition controller , it ran the coil packs and the last two fuel injectors. Funny thing is, the separate box used was a A604 trans controller box!! Lol. Engineers were saving money!!
well, code 43. Start with changing the coils packs, then start looking at wiring
Amateur
Joined: Nov 2019
Posts: 26
Likes: 0
Coil packs and wires were the first thing I did. I'm going to try the o2 sensors and see were that goes. The biggest problem with that particular truck is parts available. All the main parts are either salvage or rebuilt. I'm almost to the point of a cummins swap. The truck barley has a hundred thousand miles on it
Professional
Joined: Jul 2019
Posts: 139
Likes: 5
From: Los Angeles
40 is too low, should be 47 psi, I had the same problem and I was tossing ideas and heyyou mentioned my comp was trying to richen up the fuel injectors. Can your mechanic check long term idle adaptive memory??, I think you will find it’s way in the positive range
fuel pressure just too low
o2 sensor reading lean
miss interpreted by ECM as a coil pack problem
factory manual says 42-45 psi, every fuel pump Chrysler used in multipoint fuel injection uses 47 psi, I know, I’ve checked hundreds of them
at 40, just a small decrease in pressure will make it run lean and on a 1995 it won’t throw a lean code,
fuel pressure just too low
o2 sensor reading lean
miss interpreted by ECM as a coil pack problem
factory manual says 42-45 psi, every fuel pump Chrysler used in multipoint fuel injection uses 47 psi, I know, I’ve checked hundreds of them
at 40, just a small decrease in pressure will make it run lean and on a 1995 it won’t throw a lean code,
Administrator
Joined: Apr 2010
Posts: 87,396
Likes: 4,213
From: Clayton MI
Coil packs and wires were the first thing I did. I'm going to try the o2 sensors and see were that goes. The biggest problem with that particular truck is parts available. All the main parts are either salvage or rebuilt. I'm almost to the point of a cummins swap. The truck barley has a hundred thousand miles on it
40 is too low, should be 47 psi, I had the same problem and I was tossing ideas and heyyou mentioned my comp was trying to richen up the fuel injectors. Can your mechanic check long term idle adaptive memory??, I think you will find it’s way in the positive range
fuel pressure just too low
o2 sensor reading lean
miss interpreted by ECM as a coil pack problem
factory manual says 42-45 psi, every fuel pump Chrysler used in multipoint fuel injection uses 47 psi, I know, I’ve checked hundreds of them
at 40, just a small decrease in pressure will make it run lean and on a 1995 it won’t throw a lean code,
fuel pressure just too low
o2 sensor reading lean
miss interpreted by ECM as a coil pack problem
factory manual says 42-45 psi, every fuel pump Chrysler used in multipoint fuel injection uses 47 psi, I know, I’ve checked hundreds of them
at 40, just a small decrease in pressure will make it run lean and on a 1995 it won’t throw a lean code,