P0306 Will not stop!
01-30-2013, 04:23 PM
#32
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Year: 2000
Model: Cherokee
Engine: 4.0
In case anyone was wondering if I got it fixed this would be a NO.
It came back on Saturday while on the highway. Didn't feel like it was missing to me.
But I haven't been able to try anything else as it's at the dealer trying to get the computer to unlock. Yep Someone tried to steal my baby Sunday night.
Apparently the key immobilizer system locks out the computer after several attempts to start it with out a proper key.
They broke the SKIM module and they're none in Canada. Dealer wants $180 for it plus time spent to flash it along with all the time they've spent on it now.
I have a new computer WITHOUT the SKIM interface activated coming from Florida. Should have it by Monday.
Maybe it's always been a computer problem. I can hope.
It came back on Saturday while on the highway. Didn't feel like it was missing to me.
But I haven't been able to try anything else as it's at the dealer trying to get the computer to unlock. Yep Someone tried to steal my baby Sunday night.
Apparently the key immobilizer system locks out the computer after several attempts to start it with out a proper key.
They broke the SKIM module and they're none in Canada. Dealer wants $180 for it plus time spent to flash it along with all the time they've spent on it now.
I have a new computer WITHOUT the SKIM interface activated coming from Florida. Should have it by Monday.
Maybe it's always been a computer problem. I can hope.
01-31-2013, 01:37 PM
#34
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Year: 2000
Model: Cherokee
Engine: 4.0
I have coppers. 2nd set of them. and if you read closely you notice I tell where I've switched out 5 & 6 to see if it was a plug. Which it wasn't.
I really, really wish it was that simple.
I have more news in that it's also not the PCM.
I got a hold of a used one from the wreckers, just so I could get it out of the dealers lot. Should have taken a picture of the service managers face when it started right up. He was adamant it wouldn't work.
Driving home I thought it was nice not to see the CEL when the damn thing popped up. Sure enough P0306. Tomorrow I'll have the valve cover off and check the valve train. I'm now leaning towards an electrical fault as it comes and goes. If it was a non-functioning part it would be all the time, wouldn't it? Not hit and miss.
I really, really wish it was that simple.
I have more news in that it's also not the PCM.
I got a hold of a used one from the wreckers, just so I could get it out of the dealers lot. Should have taken a picture of the service managers face when it started right up. He was adamant it wouldn't work.
Driving home I thought it was nice not to see the CEL when the damn thing popped up. Sure enough P0306. Tomorrow I'll have the valve cover off and check the valve train. I'm now leaning towards an electrical fault as it comes and goes. If it was a non-functioning part it would be all the time, wouldn't it? Not hit and miss.
01-31-2013, 09:03 PM
#35
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Year: 1998
Model: Cherokee
Engine: 4.0 I6
I've been chasing p306 for months without resolution in my 98. And your first post sounds just like what's going on with mine. How it would come and go. To the point to where you just know when you are going to see the CEL.
I replaced my fuel injectors with 703's and it helped a bunch but it came back now..... If I
make any headway, I shall let you know. Damn light, it's like she's teasing me lol.....
I replaced my fuel injectors with 703's and it helped a bunch but it came back now..... If I
make any headway, I shall let you know. Damn light, it's like she's teasing me lol.....
01-31-2013, 09:30 PM
#36
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Year: 1998
Model: Cherokee
Engine: 4.0
My '98 had a cyl 1 misfire when I bought it. After much time and trouble, I came upon the TSB, which says to use the Mopar Combustion Chamber Cleaner and replace the valve springs. I first ran the cleaner, and the code went away for awhile. When it came back, I replaced the springs on cyl 1, which fixed it for good.
Your story sounds familiar, in that you did the "steam clean" and the code went away for awhile. I know the TSB is only for 96-99 models, but it might be worth a try to replace the springs on cyl 6. Seems like you've tried nearly everything else.
Your story sounds familiar, in that you did the "steam clean" and the code went away for awhile. I know the TSB is only for 96-99 models, but it might be worth a try to replace the springs on cyl 6. Seems like you've tried nearly everything else.
01-31-2013, 09:33 PM
#37
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
My '98 had a cyl 1 misfire when I bought it. After much time and trouble, I came upon the TSB, which says to use the Mopar Combustion Chamber Cleaner and replace the valve springs. I first ran the cleaner, and the code went away for awhile. When it came back, I replaced the springs on cyl 1, which fixed it for good.
Your story sounds familiar, in that you did the "steam clean" and the code went away for awhile. I know the TSB is only for 96-99 models, but it might be worth a try to replace the springs on cyl 6. Seems like you've tried nearly everything else.
Your story sounds familiar, in that you did the "steam clean" and the code went away for awhile. I know the TSB is only for 96-99 models, but it might be worth a try to replace the springs on cyl 6. Seems like you've tried nearly everything else.
01-31-2013, 10:00 PM
#39
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02-01-2013, 05:35 PM
#41
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02-01-2013, 05:43 PM
#42
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Year: 1999
Model: Cherokee
Engine: 4.0
I have had good luck with Mopar Combustion Chamber Cleaner (AKA: Mopar CCC)
This stuff.
http://www.jeep4x4center.com/mopar-c...4318001ad.html
This stuff.
http://www.jeep4x4center.com/mopar-c...4318001ad.html
02-01-2013, 06:09 PM
#43
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Year: 1998
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If you do decide to try the CCC, be aware that the directions on the can say to let it soak for a short time, while the directions in the TSB say to let it soak for a couple hours. Then, you are supposed to take it out, warm it up, and then do like 3 or 4 runs up to redline, with a short rest in between.
02-03-2013, 08:19 AM
#44
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Year: 1998
Model: Cherokee
Engine: 4.0L
We have the same octane levels. But there is a big difference in price.
Regular gas in Port Huron Michigan goes for around 3.25 to 3.45 a gallon.
Across the river in Sarnia Ontario where that gasoline in that Michigan gas station is refined by the way is about $5.00.
So if it won't run on regular (which it was designed for) then there is something else wrong than just the fuel. Unless it was a 4.6 stroker like Cruiser's above I doubt it would preform any better.
Any parts I threw at it were planned to be replaced anyways. Well maybe not the coil pack but now I have one to experiment with.
Regular gas in Port Huron Michigan goes for around 3.25 to 3.45 a gallon.
Across the river in Sarnia Ontario where that gasoline in that Michigan gas station is refined by the way is about $5.00.
So if it won't run on regular (which it was designed for) then there is something else wrong than just the fuel. Unless it was a 4.6 stroker like Cruiser's above I doubt it would preform any better.
Any parts I threw at it were planned to be replaced anyways. Well maybe not the coil pack but now I have one to experiment with.
02-03-2013, 08:26 AM
#45
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Year: 1990
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Some moron keeps calling the parts dept every 15 minutes cuz his pickup won't start. Had no business even working on cars. Had trouble identifying parts, didn't pay attention to advice. asked the same question over and over. After the 6th or 7th call, I told him he needed to check for spark. He asked how and I asked him if he had a helper. He said his wife was there. I told him to pull the center wire out of the distributor cap, have his wife turn the key to Start and crank it over while he held the end of the wire between his fingers. " If you have spark, you'll feel a little tingle in your fingers" I told him. He never called back.