Okay ill check the tps tomorrow AM when i do an oil change. I checked it about 10k miles ago and then replaced it with a mopar part at 157k so i didnt even consider rechecking it. I'll also be hunting for vac leaks and exhaust leaks while im under it. Its driving me nuts cause theres no CELs anymore but it still idles funky.

 

Okay I didnt get to the tps today. Life got in the way, but when I changed the oil I didnt see any obvious leaks in the exhaust or vacuum lines. Thanks for the detailed procedure ccken.

I will get to this asap

 

CEL is back on with P0432 code (100 miles since last CEL). Its always coming on at hot idle. I'll pull the FF data when I get a chance and do the TPS test.

 

Okay so the CEL is finally staying OFF. The two pre cats were bad and after getting them replaced with direct bolt on replacements from mopar (long story). They also found that the transmission mount was bad so they replaced that as well. Also passed CA smog.

It seems to idle way better but I have this super annoying rumbling/rattling noise that vibrates the entire vehicle especially in reverse and in drive under acceleration. I used to get annoyed by the skid plate rattling against the transfer case, but with the new mount the tcase is nowhere near the skidplate (seriously I don't know how I missed that - I used to even spaced the plate down with washers to keep it from rattling).

So is this a exhaust issue (like now I'm hearing exhaust leaks) or maybe the result of the new transmission mount? Any ideas?

 

Alright so at the risk of inadvertently "bumping" the thread I know how much people hate others not posting their fixes.


Took to shop and *****ed to them about the vibration after the new trans mount and 2 precats. The aftermarket was too high and caused some stuff to occasionally rattle against the floor boards so they ground the mount down to the right height of the dealer part (mopar wanted $250 for the damned thing). The new precats seem to really help with the crappy idle, so it appears thats resolved as well.

 

Hi I have black Cherokee 2000 ca emissions with rough idle stumble after motor has warmed up (only in hot weather ) or after it's been drove harder then usual.
My grandpa has replaced almost everything and even a new computer it's better but it's still there just wondering what was the final cure or if it's even fixed? I'm seriously contemplating buying a new motor or wire harness HELP .

 

Abzwenthanna,

Saw your post, I will think some about it but I'm sure someone more knowledgeable will chime in soon. Like I said the majority of my issue turned out to be the 2 cats right up near the exhaust manifold.

Welcome to the forum btw!

 

It might be vapor lock. There's a Technical Service Bulletin addressing heat soak. There's an insulation kit you can put on the intake under the fuel injectors.

 

nevermind.

Stupid forum will skip to a "related thread" if you hit the End key, then you'll post on a thread you didn't mean to...

 

A 90 degree vacuum hose terminal connector was rotted. I replaced it and the problem was solved after breaking my head for so long, it was that easy. Hope this helps! Check all vacuum hoses while your at it, it never hurts.

 

So my 2 bits on the problem. I have a 300K mile 95 Jeep Cherokee (XJ) and one night it got run hot and the next morning it was having a rough idle.
I deduced that cylindes 1,2,3, & 6 were firing but that 4 & 5 were not with an engine balance test (aka pulling the fuel injector wire harness 1 at a time and seeing which cylinders changed the idle) 4 & 5 made no change in the engine performance when they had injector harness removed, therefore they are dead/misfiring. I did the check engine light analog read and got a code 27. I cleaned my injectors manually with carb cleaner and opening them with battery voltage CAREFULLY (can fry these things) and I carefully cleaned them, well less carefully than I should have maybe. Anyways after a long witch hunt of cleaning grounds and testing injectors I settled on the SCREWDRIVER test to tell if injectors were indeed CLICKING on and off, they defintely were with harness on, and not clicking with harness off *still could be electrical problem/there is a known chafing area in the wire harness where it runs next to the engine, but right at the vehicle firewall.. So then I swapped an injector from known good operating cylinder 1 and put it in 4,-- still dead on 4 and 1 still ran with different injector showing that injectors were not the problem. Finally my nooob self came around to doing a compression test and sure enoough 150 PSI across the board except on 4 & 5, they had 0 compression. So current prognosis is blown head gasket between 4 & 5, no coolant leak detected so can't use liquid head gasket. Going to have to tear it apart and mount new gasket, see what it looks like in there anyways. DO NOT use seafoam upstream of your MAP sensor, unless i'm wrong on that it can damage the sensor and car doesn't run without it, easy to replace and test that sensor anyways. I verified my Cam sensor, TPS sensor, MAP sensor and since car runs with 4/6 cylinders on that means crankshaft position snesor is good to theortetically. Anyways hope this helps.

TLDR: Rough idle, rough acceleration, code 27, No compression in 2 adjacent cylinders==blown head gaske==not fuel injector problem (could be a valve issue too but will see later) Thanks for your help and good luck all!

https://troubleshootmyvehicle.com/jeep

 

Working on my partner's '96 Cherokee 4 liter, 5 speed; she bought new 240,000 miles ago - on starting a week ago, the fuel gauge jerked when started, then dropped from the 1/3 tank that was in it to indicate about an inch below Empty! After spending a couple hours opening up the dash and figuring out how to disconnect the fuel pump module connector in the rear to test stuff, the trouble was at the gauge - one of the 3 screws that secures the gauge to the housing and also to the printed circuit on the back of the gauge cluster had loosened just enough for the circuit to open.
So in case it helps anybody else, was an extremely easy fix aside from the time crawling around under the Jeep!

 

my mechanic Scotty told me that seafoam cleaner is built for 2 stroke motor boats and very old cars, it shouldn't be used on 90's+, he says it causes catalytic damage...
hope this information helps you

 

Great pic of 02 sensor positions…Saved- thank you