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10 CEL codes Ignition and misfire issues after highway drive


bagpiper22

New Member
Joined
Feb 11, 2020
Messages
24
Location
Norwalk, CT
2001 TJ, 4.0 i6, automatic, 116k miles

Bought the jeep in February and have been working on it on weekends: changing all fluids, oils, etc. I've got a harsh stutter as it shifts from 1st to 2nd that I've been trying to solve. Only driven it around the neighborhood mostly to test various solutions to the stuttering, and no engine problems. Took it on the highway once for a few miles, got a flashing CEL but no change n performance. Checked at home and had a few misfire codes, but cleared them and they didn't come back (with just local driving).

Last weekend took a trip 30 minutes down the highway. CEL started flashing, then solid on, then flashing, but no change in performance. On the way back home took local roads (anticipating the need to stop), and jeep started bucking a little. Pulled into parking lot. Sat for a few minutes with engine off. Started again and ran fine, CEL still flashing then on solid. For a few miles at least, then more bucking, sluggish, no acceleration. Kept pulling over, turning off then on again. Would buy me a few miles, then get so bad I couldn't keep up with even local traffic (30mph).

Finally pulled into gas station and had AAA tow me home. Pulled these 10 codes:

P0300
P0301
P0302
P0303
P0304
P0305
P0306
P1391
P0351
P0352

Recently changed the plugs to AutoLite iridium XP, properly gapped. Previous owner told me the coil pack had been replaced.

Questions:
  1. Is it likely that one actual problem component is causing all the issues, or more likely multiple problems...if so, what's the best sequence to test to rule out each potential issue?
  2. Would a bad after market coilpack cause all these issues? How can I identify the maker of the coil pack I have now? I know the wrong brand of component can cause issues.
  3. Would a bad crankshaft or camshaft position sensor cause all these issues? What's the best way to test to see which is the issue, or better and easier to just replace both?
  4. As a possible solution to my stuttering, I have the TV knockdown cable tightened...could that cause any of my ignition issues?
  5. Anything else I should be checking that I missed?

Thanks in advance!
 

CharlesHS

TJ Enthusiast
Supporting Member
Joined
Mar 10, 2020
Messages
927
Location
Carmel Mountain
These DTCs are numerous cylinder misfires, Crankshaft and Cam Position sensor problems along with Coil Rail problems.
I would check the coil rail electrical connector for oxidation or if it's loose,
Then check the harness that is routed behind the valve cover that turns forward on the drivers side to see if it has chafes or bare wire caused by rubbing against a metal stud or valve cover.
 
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bagpiper22

bagpiper22

New Member
Joined
Feb 11, 2020
Messages
24
Location
Norwalk, CT
Been a few weeks since I could work on the jeep. I bench tested the coil with a multimeter and it was within specs (.8-.9) but it was a little warm in the garage.

Took her out yesterday for a short ride and began to lose power, chugging to a stop basically. Made it to the side of the road and turned off the engine, then on again. Ran much better, though not perfect, and made it home. Pulled codes 0351 and 0352 this time.

I'm happy to get a new mopar coil but is there anything else I should check before dropping $200?

Thanks!