Here's the issue from the top. 1998 TJ Sahara has always run strong for the last 2 years zero problems with 135,000 miles. Fix one thing break 2!
I decided to go to the Dakota steering gear "update" and used the motor to bleed the power steering fluid. So lots of cranks with the coil disconnected (pulled the center wire to the dist) and my helper left the key on when we were done. It sat over night that way.
Next morning start the Jeep like normal, rev it up to make sure power steering pump connections weren't leaking, let it run for about 5 minutes, while wiping down the bottom side. Saw a couple things to tiddy up in the motor compartment, shut the motor off, did my cleaning and went to restart. (I know the steering gear has nothing to do with the issues at hand just for reference)
Here where the problems started.
It sounded like the distributor had been pulled and put in 180 degrees out, coughing and backfiring... even sounded like it tried to run backwards a couple times. Cycled the ignition key a few times (thinking I had seen a buddy who lost the pressure regulator in his fuel pump kinda sound like that when starting). And it started but ran really rough. Finally it caught up and I drove it out to the driveway to power wash and hope the issue was a fluke.
Throughout all the following issues and testing I have had no motor codes unless we created them manually to test a for each component monitoring circuit.
Grabbed my fuel line pressure gauge and connected it hit the key once 40 LBS... good. Still a rough start and now the fuel pressure was fluttering at idle. After a few days the pressure regulator gave up the ghost... had lots of issues with crappy fuel pumps (2 Carters from NAPA) went to Bosch and all's good now on fuel pressure and such (still flutters at idle).
Checked the distributor sensor and crank sensor through a buddies Snap-on reader, they're in sync and the timing is great.
Still having starting issues, check map sensor inconsistent voltage with pressure change, replaced and it's better until the PCM re-trains itself.
Next checked TPS 50% of the time no signal with quick pedal movement, fine with slow pedal (I found you!) Mopar TSP, reset the PCM and "calibrated" the TSP by putting the key in the on position and slowly move the pedal to the floor and back per the parts guy suggestion. Yup all good till the PCM re-trained itself.
Here is where I found you guys!
I replaced the PCM based on info STICKY thread on PCMs, went with Flagship One's PCM. All good fired right up with the new PCM, trained it with long idle session, calibrate the TPS, long idle and 20 miles hi-way driving.
Hello my old enemy... punch the throttle and it coughs and stutters (better with the new PCM but still there) smooth throttle movement and no probs...
Ok guys ideas?
Thanx for reading this!
Kevin
Edited: I see I missed a step in the process new cap, rotor and plugs in there as well.
I decided to go to the Dakota steering gear "update" and used the motor to bleed the power steering fluid. So lots of cranks with the coil disconnected (pulled the center wire to the dist) and my helper left the key on when we were done. It sat over night that way.
Next morning start the Jeep like normal, rev it up to make sure power steering pump connections weren't leaking, let it run for about 5 minutes, while wiping down the bottom side. Saw a couple things to tiddy up in the motor compartment, shut the motor off, did my cleaning and went to restart. (I know the steering gear has nothing to do with the issues at hand just for reference)
Here where the problems started.
It sounded like the distributor had been pulled and put in 180 degrees out, coughing and backfiring... even sounded like it tried to run backwards a couple times. Cycled the ignition key a few times (thinking I had seen a buddy who lost the pressure regulator in his fuel pump kinda sound like that when starting). And it started but ran really rough. Finally it caught up and I drove it out to the driveway to power wash and hope the issue was a fluke.
Throughout all the following issues and testing I have had no motor codes unless we created them manually to test a for each component monitoring circuit.
Grabbed my fuel line pressure gauge and connected it hit the key once 40 LBS... good. Still a rough start and now the fuel pressure was fluttering at idle. After a few days the pressure regulator gave up the ghost... had lots of issues with crappy fuel pumps (2 Carters from NAPA) went to Bosch and all's good now on fuel pressure and such (still flutters at idle).
Checked the distributor sensor and crank sensor through a buddies Snap-on reader, they're in sync and the timing is great.
Still having starting issues, check map sensor inconsistent voltage with pressure change, replaced and it's better until the PCM re-trains itself.
Next checked TPS 50% of the time no signal with quick pedal movement, fine with slow pedal (I found you!) Mopar TSP, reset the PCM and "calibrated" the TSP by putting the key in the on position and slowly move the pedal to the floor and back per the parts guy suggestion. Yup all good till the PCM re-trained itself.
Here is where I found you guys!
I replaced the PCM based on info STICKY thread on PCMs, went with Flagship One's PCM. All good fired right up with the new PCM, trained it with long idle session, calibrate the TPS, long idle and 20 miles hi-way driving.
Hello my old enemy... punch the throttle and it coughs and stutters (better with the new PCM but still there) smooth throttle movement and no probs...
Ok guys ideas?
Thanx for reading this!
Kevin
Edited: I see I missed a step in the process new cap, rotor and plugs in there as well.
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