Can't Figure out the problem

Slangy

Sgt. CulPepper
Location
Utah
So my daily driver is giving me a run for my money. It is a 99 TJ with 120,000 miles.

So there is no check engine light on, there was and I scanned it to find that the TPS sensor was bad. I changed it and thought it was going to solve the problem, nope.

Every morning I have to warm the Jeep up for 5 minutes or it will not drive, if I have been driving it and run into the store for longer than 10 minutes, I have to let it idle for 5 minutes or I won't be going anywhere. It does not matter if it is 100 degrees outside or 5 degrees outside, it has to be warmed up. If not I will start driving and everything goes fine for a second, then it just cuts out. It does not die it loses all power. The rpm's stay up without dropping but the engine makes a puttering sound and there is absolutely no power. Then it pops and there is power and then gone again. All while the rpm's never drop, it just cuts out. Then after power, loss of power, power etc it decides to run fine. Every now and again it drops rpm's at a stop light, but it never dies. It chuggs for a second and the rpm's resume their normal position.

Anyone ever have this type of problem, I am having a hard time trying to figure out what this damn thing is doing.

Thanks in advance
 

poorboyzdreamz

poorboyzdreamz
Location
Sandy
Similar problem on 88 YJ with Howell Injection. Ended up being Temp Sensor. Reading to cold and enriched air fuel ratio causing it to fall on its face and sputter until warmed up. Changed sensor and runs like a dream.
 

RogueJeepr

Here!
Location
Utah
Crank position sensor. Its on the tranny drivers side. Use an 11mm 1/4"drive socket and a bunch of wobbly extensions to get to the 2 small bolts. Thread em in by hand.
Best done underneath.
Napa parts are strongly encouraged by the xj crowd. $80ish
Replaced mine a few months ago.
 
Last edited:

mbryson

.......a few dollars more
Supporting Member
Crank position sensor. Its on the tranny drivers side. Use an 11mm 1/4"drive socket and a bunch of wobbly extensions to get to the 2 small bolts. Thread em in by hand.
Best done underneath.
Napa parts are strongly encouraged by the xj crowd. $80ish
Replaced mine a few months ago.


Same vote here but I'd go with a Mopar one if you can still get one. WORTH the $
 

rholbrook

Well-Known Member
Location
Kaysville, Ut
Similar problem on 88 YJ with Howell Injection. Ended up being Temp Sensor. Reading to cold and enriched air fuel ratio causing it to fall on its face and sputter until warmed up. Changed sensor and runs like a dream.

This can do it too. Don't you have a V8 in this TJ? The Temp Sensor is pretty cheap and easy to get to. I would try this fix before the Crank Positioning Sensor.
 

Slangy

Sgt. CulPepper
Location
Utah
This can do it too. Don't you have a V8 in this TJ? The Temp Sensor is pretty cheap and easy to get to. I would try this fix before the Crank Positioning Sensor.


The V8 Jeep is in the garage with waiting for spring, this one is my daily driver that I need to give some serious love to.

Thanks for all the replies guys, I will get checking these things and hopefully get it fixed soon.
 
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