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Rough idle after hard play

MrAnderson

NAXJA Forum User
Hey fellas,
So I went out to the dunes for my first time today. Had alot of fun romping around for about an hour with no issues cept my oil pressure got low (I checked the dipstick and my oil was really thin so I assume the high heat thinned the oil and caused a loss of pressure?) and it only got slightly above 210 for a bit.

After I was done I stopped by a gas station to air up my tires and when I started her back up it idled really rough! It's no longer doing it now but being a jeep hypochondriac it really bugged me

Any ideas or knowlage pertaining to wtf that was all about? Should I be worried?

Thanks,
Mike
 
Probably "hot soak" or "heat soak". TSB 18-031-03, GROUP: Vehicle Performance, DATE: Sep. 05, 2003

Search "heat soak" or "hot soak". Note: the factory "fix"--insulating injector no. 3, is a JOKE.

The real fix is to add a timer for the efan so that it runs for five minutes after the ignition is shut off.
 
^^ interesting! That also explains why that ugly as f heat mat is on my block haha. Someone must have had that "fix" already done. It seems like this "heat soak" is most likely the culprit indeed. I did notice that after I shut the engine off while on the dunes the temp had risen while it was off. BUT this was when I was detreming the oil situation and I had the hood up, which is a "quick soulution" according to a few articles I read, so it didn't run rough afterwards. Installing an aftermarket Efan is on "the list" already but at least now I know

Thanks alot Joe!!!
 
When were you out there? I met up with Kevin around 1130 and was at the beach til about 230.
 
When were you out there? I met up with Kevin around 1130 and was at the beach til about 230.

i got off work at 1, went out at like 2:30. i sent ya a text

only seen 2 xjs, one was an older model, red with a wide wheel base. the other was spray painted camoish, jacked pretty high and chopped as shit... a straight wheeler

seen 2 mjs as well... damn i like those things
 
The oil pressure issue is worrisome. Seems all too common on the 00-01s. I have a theory that along with the bad cylinder heads we've been subjected to some other surprises as well.
 
Sniff the oil for gas odor. May be an injector leaking fuel into the oil.
 
The oil pressure issue is worrisome. Seems all too common on the 00-01s. I have a theory that along with the bad cylinder heads we've been subjected to some other surprises as well.
honsetly i didnt really think much of the oil situation? as soon as i stopped riding it hard the pressure returned to normal(like within a minute). as i stated, i figured that the high internal heat thinned the oil out and caused a drop in pressure.

when i checked the oil after romping up and down 6 or so dunes in a row it was like water. it barely clung to the dipstick.

dont give me something else to be pananoid about!
 
Sniff the oil for gas odor. May be an injector leaking fuel into the oil.

aahhhh CRAP! my oil level is high(i JUST changed it a few days ago) and smells slightly of gasoline

well tits ona rits, now what do i do? replace oil obviously but do i pull the injectors and check for oring damage and replace as nessesary or is there some way to check for leaks? i didnt see any visual leakage after i replaced them with 748s awhile back!
fml
 
If you pull the rail, and keep the fuel line connected, then bump the fuel pump 2-3 seconds to get the fuel pressure to max, then look for the leaker, and then you should replace ALL the o'rings on ends that were pulled off (on both ends of any replaced injector and all the intake manifold side injector o'rings.

Make sure all the injector clips are still holding all the injectors to the fuel rail first!!!!!

One other possible source is a bad plug wire or bad spark plug, not firing one cylinder.

On another note, I assume from your name, that "you are the one" ???
 
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awesome!
i just swapped the injectors to 748s a month ago so might i not have to replace said rings? they are all brand new!

is this something that i can drain a bit of oil out(its like a quarter inch high) and drive for a day till i can get to it or is this destoryin stuff internaly??

and no im surely not the one... its my actual last name
 
The O rings won't cause oil in the gas. This is interesting, we have two people with the same issue posting on the same day. You might want to check the other thread.
 
Well unfortunately I just don't have any time to check the rail myself today so I'm gonna walk to work and get a ride to school :( I have a "date" with my mechanic on wednesday at 5pm and no work or school that day so ill be able to yank the rail and check for leaks prior.

Ugh
 
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Also, you can try pulling one spark plug wire at a time, to see if the idle changes, gets rough or rougher with the loss of spark to that one plug. If it gets rough or rougher then that cylinder is firing and working. If you find one that does not change, then check that spark plug and spark plug wire with an ohm meter for loss of continuity, also check the plug for carbon fouling on the insulator that can short out the plug.

You can also pull each plug and look for a gas soaked spark plug, or one that is black with carbon from running rich to help determine which cylinder has a spark problem or leaking injector.

If you have the spark coil rail pack garbage (no distributor cap and secondary wires), then disconnecting the power to one fuel injector at time is the only way to run the test above, but you can still inspect every plug. There is a color and picture condition guide for spark plugs online, just Google it, that shows what the different colors, and soil conditions look like for plugs (Lean, Rich.....)
 
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