xjwheeler10

i have a 98 xj that did the same ything and it was a combo of my ldp.. leak detection pump and an evap line that got pulled off during wheelin.

99bluexj

I swapped out the evap purge solenoid and it no longer ticks but has not fixed the engine "stutter" and I checked the codes tonight and although the light is not on, the P0455 code came up as pending. So, I'm guessing that didn't really fix anything beyond the ticking noise that was coming from the old evap solenoid. No worries, I can now cross that off the list.

Tonight, I tested the TPS with a voltmeter according to the service manual and it appears to be within range (although possibly a bit low on the WOT end of the spectrum... only read about 3.5-3.6 volts wide open. Is that a problem? Should it be higher or is it normal as long as it is below 4.49 volts?) Also, the transition was smooth from idle to WOT so can I now rule that out?

If so, what should I check next? The CPS?

dilljeepo

I would check the CPS next, ever run seafoam or something equivalent?

99bluexj

No, never used Seafoam before. Do you recommend it?

dilljeepo

yes seafoam cleans your injectors, which helps with engine stutter problems. mainly at idle but I think it works either way. worth a shot just go down to napa and suck some up theres directions on the can. worth a shot before changing any big ticket items

99bluexj

Yesterday I drove about an hour to work, still occasionally having the same "stutter" problem. The jeep sat in the parking lot from 8:00 AM until I tried to start it around 3:30 PM. It wouldn't start. After about 7 or 8 tries and while pumping the gas pedal I got it to start, BUT it wouldn't idle. As soon as I took my foot off the gas it died. Then I made another 7 or 8 attempts to start it before I finally got it running again, also by continually pumping the gas pedal while starting it. I sat in the jeep with my foot on the pedal, keeping the RPMs around 2000 for about 10 minutes to get it thoroughly warmed up before it would finally idle. Then it ran fine on the hour drive home except for the occasional "stutter" problem. When I got home and pulled into the garage, I shut it off and then started it again and it fired right up, no problem. All that being said, does this point towards a possible fuel filter problem? If not, what else?

Thanks again for everyone's feedback thus far and any additional insight you can provide is appreciated.

dilljeepo

I had that EXAM same problem when it got cold out, all I did was change my battery and that fixed all my problems. Is your battery old? Does it crank really low? Have you ever had a new battery and know how it cranks with a full battery? Anyway, that was exactly my problem, same symptoms as you just described, I changed rotor, dist, wires, plugs, IAC motor. All I had to do was change my battery. Simple test: turn on your interior lights and crank your engine. If your lights get really dim or turn off then I would suspect the battery.
FYI- my Jeep would start and die, I could drive it keeping it above idle and when I got to a stop even after driving for a couple minutes it would still die. All that was wrong was the battery.

99bluexj

To be honest, I'm not sure how old the battery is. My dome light only dims for a split second when I start the engine and normally it cranks over and starts right up with no problems. Also, a couple of weeks ago, my wife drove my jeep and had the same starting problem when she stopped at a gas station a few miles from our house, so the jeep was already warm at that point and the starting issue still happened. I'm sure it wouldn't hurt to replace the battery but I really don't think that is the issue in my case. (But I wish it were that simple.) I plan on running some seafoam through it like you previously suggested (I figure that can't hurt), but still need to figure out this stutter/fail-to-start problem that I am having.

dilljeepo

Ya I kind of stumbled on it by accident because I was working on my Jeep, it would start every time with gas but always die shortly after so my battery drained out of juice lol so I put in a new battery from another vehicle just so I could keep working on it and presto LOL if everything could be that easy...

Chucks96XJ

I had a similar problem with my old 99. came out of work, no start, but it drove there just fine. Got it started and it wouldn't idle. Popped a new battery in and some fuel line antifreeze and no issues at all. Ran fine until the day i sold it. it had about 200k mi on it.
Id go with battery and run the seafoam in there. If you do change the battery check the codes again to see if your evap code went away.

99bluexj

Over the last few weeks I have continued to try to fix this issue. After it wouldn't start a couple weeks ago, I dropped the tank and put new fuel strainers on the fuel pump and inspected the tank which was remarkably clean as compared to the strainers. Then I drove it for a couple days before the engine "stutter" occurred again. At this point, I decided to give Seafoam a try so I ran 1/2 a bottle into the throttle body, watched the smoke show, then drove it for a couple more days. The "stutter" occurred again. Then I decided to replace all the spark plugs, wires, distributor cap, and rotor. I then drove the vehicle for a couple days and it ran fine, no "stutter" problem. At this point I ran the other 1/2 bottle of Seafoam through the gas tank and continued to drive the Jeep for a few more days. It has been well over a week since I did the plugs, wires, distributor cap, and rotor and the "stutter" appears to have been fixed. HOWEVER, this morning the Jeep wouldn't start again (this happened a few weeks ago too). Same scenario as before, I could only get it started when I depressed the pedal and then had to keep on the gas until it warmed up because it would not idle on its own. After getting it warmed up, it began to idle on its own but it was a bit rough. I drove her around the block and she ran fine so I shut off the engine, then restarted it and it started right up. Tonight, I checked the voltage on the battery and it looks good (12.4 with the engine off and 14.4 with it idling). So I'm ruling that out and trying to figure out what next but that's where I'm at. In a nutshell, it seems I fixed the engine "stutter" problem but am still having occasional starting and rough idling problems. Any suggestions on what to check next?

disciplefk

I have fought a very similar problem, check your crankshaft position sensor. I am told it is a common problem.

95XJsport

Mine was doing the EXACT same thing like spot on how you describe it...get a different computer to compare with it. I struggled with mine for about 3 months before I found out yesterday, hope that helps

99bluexj

Thanks to everyone on this forum for their feedback and suggestions. I finally have solved the problems I was having. The engine stutter was resolved with a tune-up (plugs, wires, distributor cap, rotor) and the starting problem, which was a separate issue after all, was traced back to a failing check valve on the fuel pump. Despite the fuel pump still functioning properly, and now being the second time I was going to be dropping the tank while trying to figure this problem out, I decided to just replace the entire fuel pump assembly with a brand new Bosch unit and hopefully I won't have to deal with it again anytime soon. Problems solved. Thanks again!

(Oh, I still have the P0455 code coming up but from the start I have assumed that was a separate non-related issue so I'm not surprised. I'm shifting focus back to that one next because I'm getting really tired of seeing that light.)

XJeeper193

if ur jeep ever just shuts off randomly and has starting problem its probably the crankshaft postioning sensor i thought i was my fuel pump but it was just tthe sensor they tend to go bad but its a pain in the ***** to change
good luck !