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Could be a plugged cat?

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Old Jun 29, 2012 | 07:56 PM
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Default Could be a plugged cat?

My jeep just keeps coming up with funny issues. One after the other.

On my last day of a thousand mile road trip, I started having this acceleration issue - it would start "bucking", running out of fuel or whatever to the engine. It would struggle to keep speed up hills, and I really had to baby the pedal- anything over 1/3 throttle or so would make it buck around. WHen I got into a city it would die at certain points. Let it sit for 15 mins, and I'd have the thing running fine for the next 30. I went all the way home like that....

I've just recently gone through a fuel pump and got a new one when it had similar problem, I dropped the tank and cleaned it out quite a bit. Of course I forgot to change the fuel filter but it was a pretty new one at that point. So when this problem arose I really was thinking the file filter might have been restraining... I changed it and that wasn't it.

Alright cherokee forum, lets see if you guys can save my A$$ again.

cheers
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Old Jun 29, 2012 | 08:33 PM
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From: Oroville, CA
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How old are the spark plugs, cap, rotor, and wires? Worn ignition parts will cause a bucking while under a load.
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Old Jun 29, 2012 | 08:47 PM
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Originally Posted by Bustedback
How old are the spark plugs, cap, rotor, and wires? Worn ignition parts will cause a bucking while under a load.
They're all new (less than a month)
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Old Jun 29, 2012 | 08:48 PM
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One thing I'll mention too, is that if I am in neutral and rev it will go for a bit then die.
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Old Jun 30, 2012 | 12:05 AM
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The more I think about it, the more I'm feeling that again the fuel pump is acting up (hmm... 3rd one now??).. Last time I dropped the tank and then sorta wiped it down clean as far as my hands would allow.... If i do it again I'll swish some cleaner stuff in... or something. I know the seal is leaking (can't fill it all the way or it will leak out the hole for the pump) so more dust could get in...

maybe its just time to get a new tank.........?
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Old Jun 30, 2012 | 12:11 AM
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Could be a bad ground somewhere? Or a coil going bad, cps,better check some more into those things before you drop the tank again IMO goodluck!
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Old Jun 30, 2012 | 12:15 AM
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What brand fuel pump did you install?

If the answer is "airtex", I'll bet it's gone bad.
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Old Jun 30, 2012 | 12:32 AM
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From: vanburen
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Originally Posted by Radi
What brand fuel pump did you install?

If the answer is "airtex", I'll bet it's gone bad.
Mine hasn't yet lol been going for a year
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Old Jun 30, 2012 | 12:34 AM
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Haha. Not airtex, it is bosch.

I just wonder how to check these other things...
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Old Jun 30, 2012 | 12:44 AM
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Originally Posted by 88cherokeepyles
Haha. Not airtex, it is bosch.

I just wonder how to check these other things...
Search button there is a ton of great threads on here that helped me out on mine when I had a similar problem,
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Old Jun 30, 2012 | 12:48 AM
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Let it sit for 15 mins, and I'd have the thing running fine for the next 30
I'd check your fuel pressure when it acts up and see what you have. The above is common with a failing pump. Cools off and works again... for a while.
If that checks out OK, there is a procedure posted here to check your CPS voltage...might see if it's OK.
The grounds- it's good practice from what I read to refresh them periodically with the older XJ's. All sorts of oddball problems from flaky ground connections.
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Old Jun 30, 2012 | 04:47 PM
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Pressure gauge comes up with 0??

Am I doing it wrong? I just attached it to the schrader valve... turned it on and the [ressure doesn't come.
The car runs, so how could 0 be an option?

EDIT

The gauge was bad. I returned it and got another. I'm reading 23-26 psi but it goes down if given some gas.

Last edited by 88cherokeepyles; Jun 30, 2012 at 07:19 PM.
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Old Jun 30, 2012 | 08:51 PM
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When it acts up, the pressure jumps around a lot and goes around 20 psi. When really acting up it jumps down to 10.

Just took out the fuel filter (new one) to see if it was already dirty/ had more crud in as an indicator, it is good and clean.

WOuld these other electric things... grounds and cps.. cause pressure to jump down and stick around 20? Or are we looking at the pump being bad... again..
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Old Jun 30, 2012 | 10:33 PM
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I think you should invest in a new fuel tank and pump.
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Old Jun 30, 2012 | 11:05 PM
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Bad pressure like that would be pump or maybe even regulator methinks, what year is it again?
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