'99 TJ Sputters and dies but only under certain conditions??

[Guest]

Hi guys, pretty much every morning my '99 TJ sputters hardcore and then often dies while going down the street. It sounds like it totally cuts out, the rpm bounces up and down along with the check engine light flashing. Messing with the accelerator doesn't really affect it. It does this going down the road (so I really can't accelerate) which isn't cool when pulling out to turn onto a busy street. It usually putts along a little ways, and then when I have to slow down or stop, it dies. After I drive about 3 or 4 miles it drives fine and doesn't usually have any more problems.

At first I thought that the engine just needed to warm up to get past the problem so I started letting it warm up to temp before leaving the house. This wasn't the solution, I can start it in the drive, rev it up as much as I want and it won't have a problem and that's even when it's cold. But then I can let it warm up and it does the same cutting out as soon as I take off.

I tried reading the code and nothing popped up. The check engine light doesn't stay on, it only comes on when it starts cutting out. My first thought was fuel filter (I haven't had my TJ too long) but I found out that there's not one available?? My understanding is that it's pretty much a package deal with the sending unit in the tank?? I guess I'll shell out the $150 or so for the new sending unit and start there. Last month when the problem started, it only happened when going up an incline, even a small one. Anytime that the engine was under more of a load, it would start cutting out.

Any ideas would be greatly appreciated. I really hate to spend the money and then that not be the problem. I've got a pretty decent video on my phone showing what the tach. is doing when I'm driving. If you have a suggestion and would like to see it let me know and I'll email or text it to you.

Thanks and sorry for the long post
Bud

'99 TJ, 4.0, Auto

[t-rav_12]

moanin', Bud. when my xj acted like that it was my tps (throttle position sensor). the tps tells the ecm how heavy your right foot is on the pedal at any given time. there's a resistance test you can do through the plug on it. if ya can't find the specs in your srvc. manual, you can call the stealership srvc. dept. and get them.

[Guest]

Thanks for the suggestion brother! I have the day off today so I'll definitely throw that on the list to check out today.

[MR.CLIFFORD]

Bud,

Have you made any mods that could have triggered the reaction? Dropped your fuel tank, or recently installed a body lift??

There are quite a few other sensors that can cause your problem. Any of the sensors hooked up to the throttle body can cause it. You can also check the CPS sensor which has been known to give fits to 99TJ owners. I'd fish around for loose wires and check all your fuses to be sure they are functioning properly.

[Guest]

No mods or upgrades in quite a while (other than tires and stuff). I'll take a look around the wiring and connections today. I'll look at some of the fuses as well. Someone also suggested O2 sensors? I'll have to do a little reading on troubleshooting all of these. Trial and error is going to get expensive, TPS: $50, O2: $140 (upstream and down). If my daughter decides to take a nap, I'll sneak out and start taking a look.

Thanks again guys!

[t-rav_12]

Andy, why do ya ask @ the body lift? oddly enough, when i did my 1" BL, i noticed that my '02 tj learned how to idle roughly...? i thought it was coincidence and bad QT fuel. please do explain.

[Guest]

Well, still no clue! : ) I was told that you can check the O2 sensors by unplugging the "upstream" and see if that has any effect on the problem. I tried that, still had the same problem. After that, I threw in a new TPS, no luck. I really have have no clue, upcoming guesses will include: CPS, Fuel Pressure, Distributor????? Any suggestions appreciated.

Thanks

[WJonRubis]

and bad QT fuel.

Ummm.... Those are fighting words sir!

QT has higher quality tanks and filtration systems than any fueling stations in the country. It should also be noted that we are one of the last fully domestic owned and operated stations around.

ugh... /rant

;)

[t-rav_12]

no offense meant, WJon, but i found a conoco quickbreak that sells gas w/o ethanol. recently changed my fuel depot with both jeeps and my bike and they all run much better. jus' making observations...

[WJonRubis]

no offense meant, WJon, but i found a conoco quickbreak that sells gas w/o ethanol. recently changed my fuel depot with both jeeps and my bike and they all run much better. jus' making observations...

I just noticed you live in Belton. I've lived in this area for 6.5 years now. Actually I'm in Raymore now... still work over there in Belton though.

Sorry BUD, I know I'm stealing your thunder... btw did you fix the problem? (I'll see ya tommorrow bro!)

[Guest]

I HATE QT GAS AND THEIR COFFEE!! jk : ) Still jacked up man! My new gas tank skid is supposed to be in tomorrow and I can't go play unless I get this junk figured out. A friend of a friend might have chance to check it out this weekend. We'll see what happens! I'm SO ready to get this fixed

[Guest]

No KS Rocks this weekend, still haven't fixed it. I have noticed, however, that when it cuts out the speedometer starts dropping too (not along with the speed I'm going). So I don't know if this leads me towards a computer issue or what? Maybe ignition related? I'm going to try to find a better scanner that lets you take readings while driving. The one I have now, you can only use when not running and in the "on" position. Any other advice would be much appreciated! Can you post short vid's on here if you're only an on-line member?

Thanks!

[WJonRubis]

You can at least uplink some via photobucket

[Guest]

I finally broke down and took it to a mechanic. Got a call today that it was fixed: Bad coil wire and new distributor cap and good to go! Until..... I drove about 1 mile and it did the same thing and broke down : ) Gotta love it! Maybe I'll hear something new tomorrow?

[WJonRubis]

DUDE!!!!
Seriously... I mean they're good guys for giving a shot but that's what I hate about Mechanic shops... a lot of times it's just guess work. If I'm gonna pay someone to do my work, they better know something that I don't because anybody can replace a coil and distributor...

That sucks bro... Any other leads?