Ok been wrestling with this for a few months now. Hopefully get some guidance before throwing in the towel. I like doing things myself. But I’m not afraid to ask for help.
I have a 97 TJ 4.0 manual that was running good all last summer. Starting have intermittent driving issues, mainly hesitation/bucking around 2000 rpm.
Replaced all sensors, cam, crank, temp. Map, you name it. I probably replaced it. Want to do some up keep so I replaced the fuel pump, regulator, fuel rail , injectors, exhaust, coil, plugs, cap, rotor plugs, after all that it still running rough and getting worse. Every one asks “ did you use mopar sensor. No! So against my better judgement, I Replaced with Mopar pa. No difference. Before it got really bad I ran a scan tool. What I am seeing is the timing is not advancing properly (compared to when it running good) when the engine rpm’s go up when it’s running bad. At 2k it was lower that 1.5k. The flywheel looks good. Distributer was replaced a year ago, nothing abnormal there. Either I’m missing something or the computer is bad? Any help would be greatly appreciated. Before I take it to a mechanic and they just start throwing parts at it until it’s fixed or I run out of money!
I have a 97 TJ 4.0 manual that was running good all last summer. Starting have intermittent driving issues, mainly hesitation/bucking around 2000 rpm.
Replaced all sensors, cam, crank, temp. Map, you name it. I probably replaced it. Want to do some up keep so I replaced the fuel pump, regulator, fuel rail , injectors, exhaust, coil, plugs, cap, rotor plugs, after all that it still running rough and getting worse. Every one asks “ did you use mopar sensor. No! So against my better judgement, I Replaced with Mopar pa. No difference. Before it got really bad I ran a scan tool. What I am seeing is the timing is not advancing properly (compared to when it running good) when the engine rpm’s go up when it’s running bad. At 2k it was lower that 1.5k. The flywheel looks good. Distributer was replaced a year ago, nothing abnormal there. Either I’m missing something or the computer is bad? Any help would be greatly appreciated. Before I take it to a mechanic and they just start throwing parts at it until it’s fixed or I run out of money!
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