155000 miles, ran fine until it started too backfire when driving and now hard starting. changed fuel filter, and new spark plugs,wires,rotor and cap.
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1991 Jeep Wrangler Question: hard starting then backfires when driving
Answer #1ziptie12 August 19, 2012, 10:06Master
Sounds like timing chain worn out and possibly jumped a tooth. and/or possible valve problem. Do you know how to check either of these? Do you have a vacuum guage? Have you inspected plugs yet to see if it's only one cyl. being affected or all? I know you said you replaced them , but that will give you some useful info. Reply to this if you want more tips. Good luck. I also noticed a tip below my response that mentions common problem with TPS. Best get proper diagnosis first before wasting money on parts.
Replybella rose, August 22, 2012, 20:55Rookie
am starting with vac lines replacement since their look to be org ones. then looking at dist. since it is org. then going to timing chain. do you think it could be fuel pump?
Thanks for the feedback
Replyziptie12, August 23, 2012, 05:49Master
If you can test the throttle position sensor that might save a lot of time and money. A dead spot(s) in that can cause those symptoms. Did you see the mention of 'repairpals. feedback regarding that and those jeeps?
Replybella rose, August 24, 2012, 20:22Rookie
Going that way now also pull gas tank found split gas line from pump to outlet connection line. filter was no good also. Look like I need to start one end and work to other end.