Another misfire post
03-31-2015, 06:10 PM
#31
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If your mechanic is still willing to replace the PCM at no charge if it doesn't fix it, let him do that. It is one of the items on the list of possible causes.
Is it still true that it misses after start up, and straightens out in a few minutes? If so, keep eliminating items off the list of possible causes. It won't hurt to drive it, since it spends more time running well than running with a misfire.
Concentrate on those items that may be engine temperature sensitive.
Is it still true that it misses after start up, and straightens out in a few minutes? If so, keep eliminating items off the list of possible causes. It won't hurt to drive it, since it spends more time running well than running with a misfire.
Concentrate on those items that may be engine temperature sensitive.
That is a true statement, it only runs rough after startup, clears up after 30 seconds or so. It has gotten much worse since the dealer looked at it, and it's now after every startup, instead of only when cold.
The dealer said they saw coolant in cyl #1, my guy couldn't find any coolant in the cyl, and this was after pressurizing the system. He told me today that he pumped it up to 15 psi and the next day it was still at 11 psi and the cyl. was dry.
Thanks for the help!!
04-03-2015, 09:09 AM
#32
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Well bad news today, he couldn't get the replacement PCM flashed with my VIN and of course the jeep wouldn't run. I'm now thinking of pulling my PCM and sending it in to one of those places and having it checked out/repaired. Don't know what else to do, don't want to pay $1000 just for the dealer to pull the head to look. Maybe I'll take it to another dealer?? How are the control circuits tested? Thanks.
04-04-2015, 08:10 AM
#33
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I picked it up last night, started it up and it ran smooth as silk. Started it this morning, had a little bit of roughness but no where near what it was before. I guess I'm just going to drive it until it gets bad again.
04-16-2015, 06:49 PM
#36
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Well I got a call from the dealer today to tell me what they found was not the problem. They confirmed that there is no coolant getting in the cylinders. They did a cylinder leakdown test, no pressure into cooling system, pressurized the cooling system, no coolant in the cylinders. That was very good news. They are researching what else to do, something about checking signals and circuits plus they want to do a carbon clean. I doubt that is the issue but may as well rule it out. Still looking like a PCM issue. I asked if they could program the junkyard PCM to my VIN just to see if it fixed it but he said they couldn't do it, anybody know different? Thanks.
04-18-2015, 06:13 PM
#37
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I picked it up yesterday, they flashed all the computers and did a carbon cleaning on the cylinders. I don't know if the carbon cleaning was the solution as my mechanic had already done it (so he told me yesterday). It started excellent several times but now occasionally it will stumble just for a second or so. No check engine light yet. I went down to the same place today to look at a '15 Sport Unlimited in Tank. It was set up pretty much the way I wanted it, they were asking 33K, only came $500 off the price and then insulted me with an offer of $12k on mine. Needless to say I walked away. So now I'm hoping that it stays fixed. I may end up keeping it or I may just dump it, should still be able to get quite a bit more than 12k.
