Nani

Ok, this is my last try to get some answers. I feel like I've tried everything and asked everyone around me for help, but nothing seems to work so I guess you're my last hope. I live in Norway and we don't seem to have anyone who knows how to fix a jeep, so I'll try to explain the best I can with my norwegain-english

We bought a Jeep Cherokee for about three months ago and it was working fine. But after a month it startet "jumping" (it's as close as I get..) while driving. It feels like the gasspedal loses it's connection to the car for a second and then jumps back in.. Kinda.. So, we tried changing the sencor from the gasspedal (I can't remember what it's called atm and I have no clue in english) , but that didn't do it. The car is still losing it's power while driving. And to top it off, (it might have a connection to the problem - I think it does) the Jeep wont always start. If I've been driving for about 15 mins or more and we stop to refill something, wash it or whatever, she wont start up again. So we have to let her "cool down" before she ignytes again. This doesn't ALWAYS happen, but atleast three times a week.. And very much so after we've been "jumping" away for a while. It's like the car is getting tired and need to rest before we can drive again..
I tried taking out the battery for 18 hours, lettering the car reset, but that didn't help either..

Doesn anyone know what on earth this is?? And what I can do?

- Celine

blazinbob

When you say 'Jumping', what does the RPM gauge do, do the RPM's bump up or down, does the Jeep stall?

What year and motor is in your Jeep?

Nani

I'm not sure to be honest, I haven't noticed any bumping there, but my hubby believes so. And the Jeep stalls if we turn it off after driving it and not letting it rest for at least 15 minutes or more..

It's a '96 and 4L.

(The sencor we changed was the TPS sencor. And that didn't help.)

blazinbob

In your conversations with others, have you been able to narrow anything down to a specific area. A car is a car right, they all pretty much do the same thing so depending on who you spoke with I'm wondering if you narrowed it down.

First blush, I'm guessing this is a fuel delivery issue, or an ignition issue. My .02 would go for fuel system based on the fact that it seems to come and go and be heat related.

-bob

Nani

A couple of people said it couldn't be fuel related - I don't know why. I believe it might be so aswell. (But I am no expert at all when it comes to cars..) A friend of mine, who also drives a Jeep said it could be related to the ignition. We just don't know what to do to find out exactly what it is that needs fixing. But seeing as the car wont start after a while of driving it sure sounds like it having a problem with the ignition.

blazinbob

Sorry Nani, you're gonna hafta get some more details. I'm assuming this activity has illuminated your Service Engine light, maybe a trip to Autozone or an equivalent to get some system readings would be a good step.

Nani

Aight, thank you for trying

elevol92

For not starting, it could be the crank position sensor, its on top of the bell housing. As for jumping, make sure your plugs, wires, cap and rotor are ok. Check the fuel pressure on the rail.

Nani

Thank you I have told a friend of mine who works with cars what you just said, and he said he thought it migjt be the same thing. He wants to change the plugs and all that firste, before the CPS seeing as that part is kinda expensive

Crossing my fingers that this will help. I feel like a milkshake after driving to and from work.

Cherockee

Crank Position Sensor. It's a common failure part and can cause the symptom you're describing. Even if it isn't the problem it is a good preventative measure to replace before anything else.

Plugs, cap, rotor, and wires won't cause a no start when hot. Just saying... don't waste the money there if you're on a tight budget. Get the CPS first.

RTorrez1

^^This^^
From what you are describing it does sound like what I wen through when my CPS was going bad. That is the first thing that I would have replaced.
Let us know what you find out.
Good Luck!

elevol92

I didn't say it would cause a no start while hot, I said "as for jumping"

Nani

Well, changing the CPS didn't do it My hubby has been under the car for 10 hours now and still we can't seem to find out what's causing the car to "lose touch" (jump) with the gaspetal and just randomly stop in the middle of the road.. We're going for another try, thinking it might be a ignition issue.. We've checked before, but don't know what else to do..