[stahle]

1995 trooper 4x4 with a 3.5l drivetrain and manual transmission

Hey all, I've searched for hrs online trying to see if there was anything to put me in the right direction. That said, my issue is while driving I will get a random jerk every so often. I can be just slowly driving through town and it will happen, or it can happen on the highway. There are some codes set in the computer.

P0342 camshaft position sensor A circuit Low: I have checked the wiring at the plug itself and they have 5 volts at both the blue and yellow/red wire. So wiring seems fine, I cannot get the sensor out without taking off the intake manifold from what I've read. I don't have time to get into all that right now, but if necessary I will. From what I read, the ECM only uses it to start the car?

P0134 02 Sensor Circuit No Activity Detected Bank 1 sensor 1
P1133 Bank 1 Sensor 1 insufficient switching:
I checked the plug wires on the 02 sensors as well and all seems ok, I know I need to replace those, but I've cars in the past with bad 02 sensors and they never make the car run bad or cause it to jerk.

I checked all the plugs and gapped them if needed.
I checked the fuel injectors to see if one wasn't firing or acting weird, and all seem ok.

If anyone has any thoughts I'd like to hear them and discuss them. Much appreciated!

Here are some pictures of the live data

 

[Eric B]

I had a similar condition… it may be a dead spot on the throttle position sensor. Use an analog multimeter to back probe the sensor. You are supposed to see a voltage sweep between 0 and 5 volts. It will happen too fast for the computer to record. Eric

 

[stahle]

I had a similar condition… it may be a dead spot on the throttle position sensor. Use an analog multimeter to back probe the sensor. You are supposed to see a voltage sweep between 0 and 5 volts. It will happen too fast for the computer to record. Eric

Thanks Eric I will definitely check that out. I never thought about that. I'm sure the bad O2 sensor isn't helping anything either. Have one in the mail right now. I will let you know how the test goes.

 

[Eric B]

Here is the wiring diagram. The part is cheap and easy to replace. Use a magnetic torx bit with and a catch rag under it. You WILL drop the special screws otherwise and never see them again. I like to test things to confirm conditions, but sometimes replacement is quicker. This image is lifted from an original 1995 Isuzu workshop manual

 

[stahle]

Here is the wiring diagram. The part is cheap and easy to replace. Use a magnetic torx bit with and a catch rag under it. You WILL drop the special screws otherwise and never see them again. I like to test things to confirm conditions, but sometimes replacement is quicker. This image is lifted from an original 1995 Isuzu workshop manual View attachment 124544

thanks for this info I tested the TPS with the multimeter on the signal wire. it was steady all the way to full throttle and steady on the way back down tried tapping on it with testing to simulate vibration and it stayed good. So I feel it is not the TPS causing the issues. Even at idle you can feel and here it "miss" or "skip" every so often.

 

[Eric B]

Bad spark plug wire ? Disconnect them one at a time at the coil , see if it makes a difference