2001 xj missfire problem

[jdogg4]

OK I've seen a few post on this but can't find them.

I have the 2001 xj with the fire rail apposed to plug wires. well my check motor light came on so I take it to autozone and the guy ask if it's a 4 banger or 6 I said 6 he then showed me I had a missfire on atleast 4 of the 6 then it said random after that. so odds are all 6 are fed up. or could it just be the rail. how much does the rail cost. I have a 2000 xj cd and can't find the part # for it. the 2000 and 01 have the same setup so I thought I would be able to find it on that.

the plugs are the stock plugs what should the gap space on them be. I'm going to go try and pop that rail off check all the plugs then try it again. then if I have to I'll replace the rail. I'm hoping it's just the plugs cause I'm broke as hell right now.

any help or ideas on any of whats above would be great.

 

[jdogg4]

no one has delt with this issue. well the xj is over 45k so I'm replacing the plugs first.

 

[mudder]

OK I've seen a few post on this but can't find them.

I have the 2001 xj with the fire rail apposed to plug wires. well my check motor light came on so I take it to autozone and the guy ask if it's a 4 banger or 6 I said 6 he then showed me I had a missfire on atleast 4 of the 6 then it said random after that. so odds are all 6 are fed up. or could it just be the rail. how much does the rail cost. I have a 2000 xj cd and can't find the part # for it. the 2000 and 01 have the same setup so I thought I would be able to find it on that.

the plugs are the stock plugs what should the gap space on them be. I'm going to go try and pop that rail off check all the plugs then try it again. then if I have to I'll replace the rail. I'm hoping it's just the plugs cause I'm broke as hell right now.

any help or ideas on any of whats above would be great.

When I bought my 2000 I had the same problem with the miss and the check eng light. I took it back to the dealer over and over again, first it was "mabey it need's a tune up" so I said ok. then "mabey it was a valve going bad" or "cylinder may be going". keep in mind motor had 28k on it, so after numerous times back to the dealer (under warranty) it came to a carbin issue (peep's that owned it before me must have been light on the pedal). They took it out and ragged the hell out of it.and cleared the check eng light. It now has 36k on motor and no sighn of the miss or check eng light. So if you rule out the rest, don't be affraid to mash the pedal to the floor and giver' hell!! Don't know it that helps ya much but I hope ya can get something from my experiance

 

[jdogg4]

with 32x11.50s and stock 3:55 gears it gets stomped on from time to time. THanks for the imput. didn't get to it tonight like I wanted. I had a hockey game tonight and it was an hour sooner than I thought it was going to be.

 

[89xj]

gm top end cleaner would work better than stomping on it.

time to regear?

 

[steve01XJ]

jdogg,

There is a TSB on this one, and it is a simple fix. Bottom line - fuel is being evaporated ebfore it gets to the cylinder - hence the misfires. Dealer will apply a heat shield to the rail, reducing the evaporation risk and eliminating the misfires. Don't waste any more money until you get them to look at this one. I just had to do this on my 2001 last month and I only have about 21000 on mine. It runs great now.

 

[jdogg4]

89xj yes way time to regear but I'm working on a ford 8.8 with disks breaks and I'm going to go with 4:56s and a locker. When that is about ready to go in I'm going to get the front regeard aswell. I'm going with 4:56s cause I want to run 34s or 35s after the longarm kit is ready to go on.

and the heat shield is that the one they had the recall on cause they forgot to put it on. Cause I allready have that taken care of. But I will check into it. Thanks

 

[Bryan C.]

I have noticed a few Xjs coming into my shop with the same complaint. Yes there is a TSB for a #3 injector heat shield, it does help some. There is also a flash update for the PCM that changes when the cooling fans come on, so the engine runs cooler. These combined will take care of most misfire conditions. The misfire usually arises after the engine is hot, then shut off for about 10-15 minutes, then restarted. If you have the misfire at other times, like when cold or while driving you may have other problems. One of my buddies with a 01 XJ that I did both the TSBs on still had the misfire problem. He resolved the issue by installing a 180* thermostat. Jeeps come stock with a 195* thermostat. He said it cleared up the problem. Go to your local Jeep dealer for the injector sleeve, and see about getting the PCM software flash update too. You may just want to try the thermostat first and see what happens.

I have the same condition on my 96 XJ when on the trail. After the engine gets hot and I shut it off, it misfires real bad and turns on the check engine light. It clears up and turns the light off after a day or two, so I don't worry too much about it, but I do plan on installing the 180 thermostat soon.


Bryan

 

[jdogg4]

ya when driving for a long time then shutting it off and then starting it back up with in like 10 20 min it just runs like crap have to sit on the gas a bit for like 10 seconds then back to smooth running again. Is this under any recall notice or anything.

 

[jdogg4]

never updated this. plugs are swapped out. THey had some good ware on them and the gaps were a bit much on most of them but one that was way to small of a gap. Either way they needed swapped out. I let the system reset and the light is off now and its running much smoother. not sure how about that stuttering thing it was doing but hope it's just the plug issue still and if so that was taken care of with the swap.

 

[RE-xtremeXJ]

I am reading this post having the same conditions and problems with my 01 XJ as described above.

-I was wondering if the solution that someone posted worked for anyone.

-They said that the dealer can supply a heat shield for an injector or the fuel rail??, along with a flash update for the PCM.


Thanks for any info you can give, Mike.

 

[steve01XJ]

Yes, I went to my dealer and they installed the heat shield on the fuel rail and provided a flash update to teh CPU. Haven't had a problem since then. It's been over a year. There is a TSB on this one.

 

[Ryan4x4XJ]

Found this thread while searching

I had the same problem in my 2001, but I dealt with it a few years ago. I heard about the fuel evaporation problem so I removed the silver heat shield on top of the engine and the problem went away.

 

[RE-xtremeXJ]

Found this thread while searching

I had the same problem in my 2001, but I dealt with it a few years ago. I heard about the fuel evaporation problem so I removed the silver heat shield on top of the engine and the problem went away.

If you did have a fuel evaparation problem then by removing the heat shield- your allowing all the heat from the exhaust manifold to hit the fuel rail and potentially make it even hotter.

I still have this problem, it comes and goes. More so when its warmer weather and i do a lot of driving around.

-Mike

 

[DenLip]

ya when driving for a long time then shutting it off and then starting it back up with in like 10 20 min it just runs like crap have to sit on the gas a bit for like 10 seconds then back to smooth running again. Is this under any recall notice or anything.

I had this sort of problem three times while on a road trip across PA... the PA Turnpike is all Sunoco gas, and I had two tankfuls of it. I've never had any inkling of such a problem otherwise... before or since. I normally run Exxon or BP.

I blame the gas.

Den

 

[RE-xtremeXJ]

You could have a point but i would like to know what is actualy causing the problem. I used to run no name gas cuz they are always the cheapest, but since i switched the shell it happenes much less often. Also i run 89 all the time.

I took it to the dealer several times and got charger that damm co-pay just for them to tell me its a fouled spark plug. I know its a fouled plug, i keep changing them- i want to know what is causing the plug to foul!!:helpme:

 

[JonY]

I just had the same problem on my 01 Cherokee with about 98,000 miles on it. After the engine had been running for a few hours, then shut off, then re-started, I got a very rough idle and the engine light come on. The code reader said misfire in cylinder # 4. I have experience it twice now, but the check engine light only came on the 2nd time it happened. In both cases it cleared up by the next morning.

Is this something that needs to be fixed? Will it cause any damage?

 

[casm]

Is this something that needs to be fixed? Will it cause any damage?

Whoa... A 4-year-old thread that hadn't been replied to in two years... Cool

Anyway, you're probably having the #3 injector heat soak issue common to 2000 XJs - basically, the fuel's evaporating before it can make it out of the injector and into the cylinder. See this post for more info and the TSB procedure on fixing it.

Also, at some point a debris shield over the manifold should've been installed. Take your VIN to the local dealer and ask for the recall history on your vehicle; they should be able to tell you if it's been done or not. Once complete, you should see a metallic mat (which disintegrates after a few years) over the intake manifold.

 

[Tim_MN]

Hey, at least the guy used the search before he posted.

JonY also look at some threads on the fuel pump check valve. A failed check valve will cause long cranking, rough initial idle and sometimes even check engine codes.

 

[casm]

Hey, at least the guy used the search before he posted.

Hence the '' at the end of my comment

JonY also look at some threads on the fuel pump check valve. A failed check valve will cause long cranking, rough initial idle and sometimes even check engine codes.

Good point. Haven't had mine go out yet, but God knows it's not unheard of...