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Chugging/Stalling out

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Old Apr 20, 2014 | 07:22 PM
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Year: 1992
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Default Chugging/Stalling out

Hey, so my 92 has started having some issues. I was wondering if you guys might have an idea where I should start.

For a little back story, I've been having to prime it before starting because of what I assume is a bad check valve. After a couple minutes of sitting off there is zero pressure in the line. Recently though, priming stopped working. i can prime it and hear the pump kick on like 10 times and it doesn't seem to take any less cranks than if I don't prime at all.

Now when I'm driving it will sputter and hesitate as I try to accelerate, and with constant pressure on the gas pedal it will slow and then suddenly pick up and shoot forward. It also idles pretty chaotically, sometimes normal, sometimes dies off.

Fuel pump finally gone? I might try an ignition coil. The cap and rotor are new, as are plugs and wires, but the coil isn't. I read that might cause those symptoms. What do you all think? Help is appreciated.
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Old Apr 21, 2014 | 08:24 PM
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So I unplugged the TPS and it seemed to run better without it so....I think I'll be putting a new one of those on...We'll see how that works.
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Old Apr 22, 2014 | 07:19 AM
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Try the TPS if you want.

I'm guessing your fuel pump is dying or the hose to the pump inside the tank is split/bloated/collapsed/ FUBAR.
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Old Apr 24, 2014 | 10:06 PM
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Okay, so I put a new TPS and MAP sensor on, and I'm putting on an ignition coil and doing plugs, wires, valve cover gasket, and new CCV valves/cleaning hoses tomorrow. I haven't had a chance to get it on the road with the new sensors, but it idles fine at this point. The only issue as it sits is that when I tap the gas pedal it basically shuts the engine off for a split second, then roars back to life. Doesn't happen with a slow push, and revs fine, but just a quick tap makes it hiccup.

I know the check valve is busted, but I feel like if the pump were bad it wouldn't rev so well and such. Also I do have a new fuel filter on it, and replaced the fuel regulator about 2 months ago.

Any thoughts? Should I get my hopes up that I'll get it sorted out with new electrical and a clean CCV system?
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Old Apr 24, 2014 | 11:03 PM
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I get this occasionally as well, always thought it was electrical, looking forward to you finding out what it is.
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Old Apr 24, 2014 | 11:30 PM
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Originally Posted by unidentifiedbomb
I get this occasionally as well, always thought it was electrical, looking forward to you finding out what it is.
Your fuel injection system is totally different than his. How many, and which ones, of my "Tips" have you done n that old 88 of yours?
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Old Apr 25, 2014 | 01:04 AM
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Originally Posted by cruiser54
Try the TPS if you want.

I'm guessing your fuel pump is dying or the hose to the pump inside the tank is split/bloated/collapsed/ FUBAR.
i just had this happen with my 92. it would take 3 primes just to reach 15 psi and would drop to zero after a few seconds. i pulled the fuel pump to replace it and found the rubber elbow was not tight and the pump sock/screen was coming apart. the pump itself is still good as far as i know. i replaced the pump anyway and kept the old one as a spare. i would recommend to anyone who is having fuel pressure issues to check the rubber elbow hose. it takes about 5 minutes to pull the pump.
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Old Apr 25, 2014 | 01:06 AM
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Originally Posted by OldLaredo
Okay, so I put a new TPS and MAP sensor on, and I'm putting on an ignition coil and doing plugs, wires, valve cover gasket, and new CCV valves/cleaning hoses tomorrow. I haven't had a chance to get it on the road with the new sensors, but it idles fine at this point. The only issue as it sits is that when I tap the gas pedal it basically shuts the engine off for a split second, then roars back to life. Doesn't happen with a slow push, and revs fine, but just a quick tap makes it hiccup.

I know the check valve is busted, but I feel like if the pump were bad it wouldn't rev so well and such. Also I do have a new fuel filter on it, and replaced the fuel regulator about 2 months ago.

Any thoughts? Should I get my hopes up that I'll get it sorted out with new electrical and a clean CCV system?
mine did this also with the loose fuel pump elbow. after replacing it the jeep has great throttle response off idle
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Old Apr 25, 2014 | 07:41 AM
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I think it's a combination of old rubber parts and new fuels causing the elbow failure.
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Old Apr 25, 2014 | 07:45 AM
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Good tip on the fuel pump elbow. The stuff I'm doing today and tomorrow needs to be done anyway, so I'll get that out of the way and report back. If this doesn't solve it, I'm definitely going for the pump next. Just wish I didn't have a mostly full tank...
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Old Apr 25, 2014 | 01:12 PM
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Ugh. Plugged in new ignition coil before removing the old one (cause I'm smart). Zero change in symptoms. So I'll return that sucker and I guess I'm buying a new fuel pump.
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Old May 3, 2014 | 05:42 PM
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Ugh. Got the new fuel pump in. Why the hell didn't you guys tell me it's such a PITA to put the new lock ring on?? Hmmmm??

Anyway...since I'm smart....can't see if it works because the oils drained and I'm about to do the VC gasket....and the oil pan gasket....and plugs, wires, etc....

I'll get back to y'all tomorrow and let you know if the thing runs.
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Old May 3, 2014 | 05:46 PM
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P.S. Here's what my old strainer looks like. Yum.
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Old May 7, 2014 | 09:47 PM
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finally got the trainwreck that was my valve cover cleaned up. It was so black inside it looked like parkerized steel. And the CCV ports looked like someone coated them in axle grease and threw them in a sandbox.

Got the VC and gasket in place, but calling it a night because I'm tired, and its not lining up just right.
Any tips on getting the VC and gasket to fit properly? Or should I just keep wiggling everything around until it falls into place?

Also, pulling the oil pan tomorrow or the next day. Any tips there? Just gonna do a basic clean out of the sludge and new gasket.
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Old May 7, 2014 | 10:05 PM
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Felpro gasket or cheapie old cork ?
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