Running rich, sputtering under load

Drossiter

New Member
Joined
Oct 13, 2021
Messages
7
Location
Jacksonville nc
95 wrangler 4.0 5 spd

I have a problem that has me scratching my head. I had an issue with it running rich, sputtering, and missing. When accelerating, it spits and sputters worse than when just revving standing still. I did a compression test and discovered the piston rings were leaking. I rebuilt the motor. Bored 20 over. Rebuilt head. All new everything. Put it back together and still have the same problem.

Replaced distributor, cap, rotor, wires, plugs, coil, fuel pump and filter were replaced due to low pressure. New injectors, IAC, MAP, and TPS. New temperature sensors, new CPS.

Couldn’t figure it out so I took it to one shop. They diagnosed it with a bad alternator, replaced it no change. Took it to Jeep, they diagnosed it with a bad PCM. Replaced it, no change.

I am getting codes 13 and 24. I’ve replaced the TPS four times. I’ve tested the signal code and I’m getting proper voltage readings through to WOT. I’m stumped.

I did discover the seal on my gas cap is broken so I’ll be replacing that but I can’t imagine that’s the problem. Any suggestions would be great. Jeep doesn’t want to mess with it anymore.
 
Have you done a fuel pressure test yet? Idk about the seal in the gas cap either, but I would think that could be affecting your fuel pressure. However, I am a noob at this and am taking the best educated guess.
 
Fuel regulator was replaced. I get 38 at the rail and it jumps to about 44 when I disconnect regulator so that is good according to FSM. O2 has not been replaced. I would like to test that but not sure how. Can’t seem to find anything about it in the FSM. I could be overlooking it as it has over 2k pages.
 
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I do want to add my TPS voltages on the signal wire range from .7volts to 3.8 at WOT. Smooth transition. Even tried taping it while moving through the ranges to see if the jolts caused any erroneous readings. Checked out good. I’ve read in other forums that these things only like MOPAR TPS. I haven’t thrown a mopar one at it yet. I’m trying to test everything I can do I’m not just throwing random parts at it in hopes something works. Jeep can’t figure it out and I’ve already wasted money on a computer and a flash for it not to solve anything.
 
I understand the Mopar only bit but Ive used both and really found no difference. matter of fact I have 3 TPs'es and the Mopar one looks identical,numbers and all to one of the aftermarkets. Geez..you've cover so many bases to date but the 02 sensor. Most will tell you do NOT use a Bosch one,get a NTK sensors. My 91 did make a code for slow to heat so you should get a code(s) for a bad one(s). What plugs are in it? Ive read guys saying their jeep ran like crap and threw codes after installing some of the infamous,high dollar super plugs. Just a thought there. Silly stuff like a rat building a condo in your air box maybe choking it off?? A chafted wire on the main harness perhaps. The uglies are endless.
 
Update: I replaced the injectors but decided to test them anyways. Three were leaking and weren’t producing the resistance they needed. Replaced them with the old ones that I knew were still good. Runs like a raped ape now. Thanks for everyone’s help.
 
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Strange...wonder if they were Amazon/China bootleggers. After working in the auto parts industry I became no fan of Bosch. Might as well be Home Depot employees building their parts.