jonwalden68

My 96 grand Cherokee 4.0 runs great but it will randomly about once a day have a bog out cut out feel then powers right back and keeps going good i put 100 miles a day on it I just want to figure out what it is? No check engines and no codes any idea what to do i don't want to just throw parts on it please help

jonwalden68

The motor and everything is very clean and been well maintained just the darn cutting out/bogging out and it's mostly right after a stop when taking off easy

dave1123

I would say check you throttle position sensor. It may be sticking.

jonwalden68

I'm gonna do that today

jonwalden68

Someone says it could be map sensor could it be that? It's hard to take to mechanic when it's only doin it once a day at random times I can do anything to duplicate it

dave1123

Check ALL your vacuum hoses for cracks, even slight ones. It sounds to me like you have a momentary lean condition just off idle and it takes a few seconds for the PCM to recognize it. It could be a sticking piston in the IAT (idle air control).

jonwalden68

I checked all the hoses yesterday and had a shop look over them too they were good. And they didn't have any codes on file. I just hate to throw parts at it if it's not a tps

jonwalden68

Oh and it's idles fine it's always when just barely into the pedal them will bogg kind of buck for less then 5 seconds then kicks right back in going good

Red River T

My 97 has a similar problem: if I drive across a big parking lot real slow, 5 mph or whatever, when I pull out on the street if I give it too much pedal, it falls on its face. It's still running, but won't accelerate. I have to lift, then it will do OK when I get back on the gas.

I need to do a lot of service to mine I guess. There is a thread on here I saw in June or July about cleaning the Idle Control. I intend to do that when I can be down for a day. Also, there are other threads that talk about the PCM (powertrain control module, aka "computer") wiring harness connectors going bad. Apparently the soldered wiring joints inside will crack and cause it to momentarily lose the connection and do things like your cut out. Some people have taken theirs apart and re-soldered the connections. I intend to search for the youtube how-to video they mentioned and then check mine for cracks, if nothing else goes wrong in the meantime.

jonwalden68

I'm checking computer today

93_xjcherokee

Crank sensor

jonwalden68

I was thinking same thing but now I have a code showing all cylinders are misfiring

dave1123

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i8uwithalime

[QUOTE=jonwalden68;2942209]The motor and everything is very clean and been well maintained just the darn cutting out/bogging out and it's mostly right after a stop when taking off easy[/QUOTE
Evap is what I read. I then read to check gas cap to make sure it is sealing. Sure enough that is all it was. Pretty crazy. It wouldn't let me go past 50 or so. Also check code by turning your key to start 4 times. Good luck.

jonwalden68

Still haven't figured it out