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Topic Review (Newest First)
08-06-2012 04:29 PM
ARTC
Recall for programing ecm

I have been beating my head on trying to get my 02TJ to start. I have finally decided to by a replacement ECM. When we took the ECM out of the Jeep, I noticed there was a white smaller sticker over top of a larger same type of sticker. This top sticker has bar codes and S/N numbers Chrysler P/N and Module S/N.

I asked the mechanic at the garage why the 2 stickers, he looked up the factory recalls, and in 03 there was a factory recall to reprogram the ECM do to a misfire problem.

I don't know if this is your problem or not but it is worth checking out.
08-03-2012 02:47 PM
sargeparrish
Quote:
Originally Posted by sethhicks
OK so I just bought a 2001 wrangler 4.0L Automatic with 135k miles and drove and sounded great during the test drive as soon as I drove it off the lot the next day I was driving about 65mph and the check engine light started flashing I went and got the codes checked and I got random misfire and then a misfire in a couple cylinders ... since then I changed the plugs myself and also took it to a shop for a diagnostic and they said the plugs, coil pack, and the sensors were all good but there was some really bad carbon build up so they cleaned up the entire throttle body and the exhaust valves and all that good stuff and told me it should be good to go and if that didnt fix it I would need to get the head re done and they quoted me 1600 ... so I took the highway home reaching speeds of around 80 and it drove great but the next day on my way to work at high speed it misfired again same codes Ididnt feel anything but the cel was flashing ...I 'm going to take it somewhere else for a second opinion so hopefully its not quite as expensive of a fix but I was just wondering if anyone had any other ideas of what it might be ... It only happens at highway speeds above 50 or 60 and also will I do anymore damage by driving it back and forth to work?
i had the same prob. i replaced the cmp and ckp. then had to replace them again. bad new parts. i replaced fuel pump all sensors on the throttle body. plugs wires trying to figure it out.
08-03-2012 12:32 AM
pi55edoff I had my top end cleaned out in my 2000 tj and my compression went up to 30lbs higher in almost every cylinder. Cost me $250 but it was a heck of a lot cheaper and faster turn around. I get the misfire code in #1 all the time. Changed plugs and crank sensor. Also cleaned out my IAC. After each of these it would run great then back to the old crap. Somedays it runs sweet n other horrible. Just ordered an upstream O2 sensor today so hopefully that'll help. Have any of u noticed if it loads up on fuel/runs rich n can smell gas when u shut it off? I have 165000 on it. Mpg has gone from 15/16mpg to 11/12mpg.
08-03-2012 12:04 AM
blackowlar and it could also be a cam sensor going bad and not telling ur ecm what position they are in. giving u multible misfires. which also maybe why u dont feel it happening, cuz its not. just that sensor. hope this helps put u in the right direction.
08-03-2012 12:01 AM
blackowlar sethhicks...does it cut off all together and take a few to recrank? if so try the cranks position sensor. i just went through all this as well. they said everything from pump giving out to cam sensor to ecm. if it does just random misfire and cut off try pouring clod water on the crank sensor. if it fires right off, that maybe the prob. its 80 bucks or so but it has to be done just right. calibrated an all. local good mech should be able to do it for 120 or so including sensor. alos i read that in high speed misfires it could be 02 sensor reading to much fuel and killing it. dont know how true but maybe ur prob.
08-02-2012 09:58 PM
sethhicks ok I ran the fuel pressure test it came back good right at 49.5 and then I did the compression test and here's what I had
1 - 110
2 - 100
3 - 100
4 - 100
5 - 100
6 - 100

the chilton manual said that 100 is the minimum and its ok as long as there isnt more than a 25% difference so i think thats ok ... and I wanted to clarify along with the random misfire over time I have gotten a misfire in each different cylider but not all at the same time.. any advice on where I should go from here ... and also is it safe for me to be driving it? cause right now it's my daily driver ... thats why I bought it in the first place lol all help is much appreciated ... and also it is kind of random when it happens some times when I drive home from work i dont get any flashing cel its just on steady from the last time it misfired I think its stange that I dont feel anything while driving
08-01-2012 09:54 AM
MickeYJ
Quote:
Originally Posted by prettyinpink
I'm having the same issue with my 4.0 2002 that I purchased 3 months ago. Ive done full tune up, transmission service, and replaced coil as well. I seem to have loss of power. I can be flooring it at 2600 rpms and out of no where I pick up power for about 10 second then lose it again. I as well get the flashing light at 65+ with p300 code. But it always randomly comes on. Not every time I drive.
Mine did it, three mechanics later n still doing it UNTIL I changed the TPS myself ($35) thx to people here n its been fine ever since!
07-29-2012 11:21 PM
SeVeReDiStOrTiOn I'd do a compression test as your next step. That shop should've done it way before recommending head work...don't take it back there. Makes you wonder how well they tested everything else. Random misses can be tricky because there's either a few small misses and the pcm can't tell which cylinder or the whole bank is just randomly misfiring. It sounds fuel or timing related since you both have new plugs/known good coil.

Anyway, you should be able to rent the compression tester at autozone or somewhere else that rents tools. Also while you're there get a fuel pressure tester. Googling will give you instructions on how to do it.
07-29-2012 10:30 PM
prettyinpink I'm having the same issue with my 4.0 2002 that I purchased 3 months ago. Ive done full tune up, transmission service, and replaced coil as well. I seem to have loss of power. I can be flooring it at 2600 rpms and out of no where I pick up power for about 10 second then lose it again. I as well get the flashing light at 65+ with p300 code. But it always randomly comes on. Not every time I drive.
07-29-2012 10:23 PM
sethhicks
2001 4.0 misfire Help!

OK so I just bought a 2001 wrangler 4.0L Automatic with 135k miles and drove and sounded great during the test drive as soon as I drove it off the lot the next day I was driving about 65mph and the check engine light started flashing I went and got the codes checked and I got random misfire and then a misfire in a couple cylinders ... since then I changed the plugs myself and also took it to a shop for a diagnostic and they said the plugs, coil pack, and the sensors were all good but there was some really bad carbon build up so they cleaned up the entire throttle body and the exhaust valves and all that good stuff and told me it should be good to go and if that didnt fix it I would need to get the head re done and they quoted me 1600 ... so I took the highway home reaching speeds of around 80 and it drove great but the next day on my way to work at high speed it misfired again same codes Ididnt feel anything but the cel was flashing ...I 'm going to take it somewhere else for a second opinion so hopefully its not quite as expensive of a fix but I was just wondering if anyone had any other ideas of what it might be ... It only happens at highway speeds above 50 or 60 and also will I do anymore damage by driving it back and forth to work?

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