idle problems// backfire// no power on accelaration - Page 2 - JeepForum.com
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post #16 of 29 Old 12-08-2010, 06:15 PM Thread Starter
thundering89
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dang. ill replace the filter again and see if that helps

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post #17 of 29 Old 12-08-2010, 07:32 PM
StevenXJ
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Is your check engine light on?
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post #18 of 29 Old 12-08-2010, 10:10 PM
Topgun514
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Quote:
Originally Posted by cruiser54 View Post
You would check the TPS first when he has only 15 PSI of fuel pressure and 31 to 39 is required?
Woops, my eyes scanned right by that. I got all excited when someone had the same problem by the sounds of it as me. That is next, a backfire upon throttle is typically a fuel feed problem.

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post #19 of 29 Old 12-09-2010, 04:52 AM
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Quote:
Originally Posted by Topgun514 View Post
Woops, my eyes scanned right by that. I got all excited when someone had the same problem by the sounds of it as me. That is next, a backfire upon throttle is typically a fuel feed problem.
Appreciate your enthusiasm!! Unfortunately , in the world of auto repair many symptoms can have multiple causes and what fixed something for you or I may not fix something for the other guy. Best to test your way to a solution. Sometimes this requires eliminating things through a process involving making sure what the problem ISN'T. I prefer to attempt these repairs/diagnoses without throwing parts at a problem, but to check connections, through visual inspection, search for vacuum leaks, make sure basic maintenance is done, etc.
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post #20 of 29 Old 12-10-2010, 12:52 AM Thread Starter
thundering89
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changed the filter, new injectors, used a more accurate pressure gauge. 31-32 psi. starts right up now, but it still idles rough and still back fires into the intake. no power when in gear.

i was told to remove the exhaust to check for restriction. could that be an issue?
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post #21 of 29 Old 12-10-2010, 04:28 AM
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A clogged catalytic converter can cause those kinds of issues.

You can test for a clogged converter/restricted exhaust using a vacuum gauge...
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post #22 of 29 Old 12-10-2010, 11:50 AM
Mighty Thor
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If every thing else checks out You need to consider timing chain or worse (like mine did) a bad camshaft lobe. I Had the cam go bad on my 93 and it developed exactly the symptoms you describe.
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post #23 of 29 Old 12-11-2010, 11:59 AM
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weak valve springs also do this
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post #24 of 29 Old 12-11-2010, 12:01 PM
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how about checking the fireing order , you sad you changed the plugs maybe you put a wire in the wrong place
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post #25 of 29 Old 12-11-2010, 02:05 PM
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how about checking the fireing order , you sad you changed the plugs maybe you put a wire in the wrong place
No fooling. Worth checking if you haven't verified this already.
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post #26 of 29 Old 12-12-2010, 09:45 PM Thread Starter
thundering89
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no worn cam, no clogged exhaust, and firing order is right. the only thing that ive been consistently told was bad timing chain, bad valve, weak valve spring, or sticking lifter. im going to pull the motor apart and do a complete rebuild. send the complete block to a machine shop to be inspected.

i figure i owe it to my baby to have a new heart. lol
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post #27 of 29 Old 12-12-2010, 09:49 PM Thread Starter
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its going to be a while before i can rebuild it though. my jeep is in california and im in arizona. dam school.

if any one wants to tow it for me i would be more than happy. lol
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post #28 of 29 Old 12-28-2012, 07:51 AM
mhaner7
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I am losing power and sluggish and backfiring

On my way to work this morning my jeep would not go anywhere and was running sluggish and was backfiring under the jeep as from exhaust any suggestions
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post #29 of 29 Old 12-28-2012, 03:04 PM
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On my way to work this morning my jeep would not go anywhere and was running sluggish and was backfiring under the jeep as from exhaust any suggestions
wrong forum. You have a TJ.

If you own a Renix Jeep, you'll want to check this out.

An index to over 30 write-ups can be found in the link below

www.cruiser54.com

My Jeep Technical Photos

http://www.cherokeeforum.com/g/album/1725214
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