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Old Sep 26, 2012 | 12:22 PM
  #1  
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From: Near Salem, OR
Year: 1999
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Default PCM (computer)

Has anyone had to change their PCM on their Jeep. My mechanic told me the missfire has been traced to a malfunction in the pcm and it has to be replaced. I've got the info for a reasonable shop that flashes these locally.

Has anyone bought aftermarket/refurbished computers online? And if so, what company and was it of good quality?

Thanks in advance!
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Old Sep 26, 2012 | 01:02 PM
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What year? 99? He's ruled out the more typical causes of misfire I assume?

I've never bought a refurb PCM. Given that aftermarket "rebuilders" can barely get a power steering pump or gear right, I'm not sure I'd trust them on a PCM. Perhaps another member has a source other than OEM or Scrapyard they can recommend.
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Old Sep 26, 2012 | 01:54 PM
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yeah, I was getting misfire on #5. Full tune up done, still nothing. TPS sensor showing bad as well, replaced and still nothing.

Finally took it to the shop and the injector on #5 was totally dead. I replaced it and still missfiring. I took it back and he checked everything all the way up to the pcm, all cables in tact and checked ohm readings, the injector gets intermittent signals. Service Bulletin shows that manifold heat is known to kill #5 and when that happens in some cases it can short out the pcm. Apparantly there is a kit from the dealer that is like a heatshield you can wrap around that injector to prevent that from happening.
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Old Sep 26, 2012 | 01:56 PM
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I called the Jeep dealer here and the pcm is backordered, given timeframe of Nov. Price is $825 not flashed. Online for refurbished ones I saw going for $200 already flashed.

I just don't know if there is a trusted source that people know about.
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Old Sep 26, 2012 | 02:01 PM
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Sorry, a little more info. Local pick-a-part has then for $125.. and I would have to pay $125 to have it flashed at another shop.

All I know I don't want to pay the dealership $800 price..
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Old Sep 26, 2012 | 04:32 PM
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This member:
https://www.cherokeeforum.com/f2/rep...mputer-142583/

was able to use a scrapyard PCM without having it flashed. Drop in and go.
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Old Sep 26, 2012 | 05:15 PM
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Originally Posted by Radi
This member:
https://www.cherokeeforum.com/f2/rep...mputer-142583/

was able to use a scrapyard PCM without having it flashed. Drop in and go.
Did it affect the mileage readout?
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Old Sep 26, 2012 | 05:54 PM
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Why do you want it flashed so.bad...i pulled one for my 90 out of anpther at jy, no flashing, just 50 bucks to the jy and it wprked just fine
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Old Sep 26, 2012 | 06:02 PM
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got a PCM problem my pcm number is 795AD now im using AF but im order mine from ebay for 169 from here http://www.ebay.com/itm/170525721908...84.m1423.l2649

not yet try it ,
my problem was crank but not start all the gauges down when the Gauges go up it start it was PCM problem cant find the exact number so order it from this company now the AF is working but some time stall when pressing clutch its drivable but i just want it to be perfect ,

i well try it and let you now they ship on time also the price is good in my opinion.
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Old Sep 26, 2012 | 10:18 PM
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Originally Posted by 99purpleXJ
Did it affect the mileage readout?
Odometer reading is stored in the instrument cluster. Changing the PCM shouldn't affect it.
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Old Sep 27, 2012 | 03:13 AM
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Originally Posted by Radi
Odometer reading is stored in the instrument cluster. Changing the PCM shouldn't affect it.

Thanks! That's what I was worried about if I just plug one from a junk yard. Besides the dealer is not even an option, not just because of expense but because they are backordered and after checking for info at various ones I found out they may just stop selling them.

Not that I really wanted to pay to have one flashed either, it's just what I was told initially but after more reading found out it's not required for this year.

Tomorrow, time to call the local pick your parts for jeeps in stock.
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Old Sep 27, 2012 | 03:14 AM
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Originally Posted by weld3z
got a PCM problem my pcm number is 795AD now im using AF but im order mine from ebay for 169 from here http://www.ebay.com/itm/170525721908...84.m1423.l2649

not yet try it ,
my problem was crank but not start all the gauges down when the Gauges go up it start it was PCM problem cant find the exact number so order it from this company now the AF is working but some time stall when pressing clutch its drivable but i just want it to be perfect ,

i well try it and let you now they ship on time also the price is good in my opinion.
I saw that sellers ad on ebay. Let me know how it works out for you.
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Old Sep 27, 2012 | 07:21 AM
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I've heard to stay away from refurbished pcms. There was one in my XJ and it took a dump before I bought her. Replaced it with one out of another XJ the guy had and she took off.
He told me gettin one that wasn't refurbished is the way to go. Idk how true that is though.
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Old Sep 27, 2012 | 11:22 AM
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Originally Posted by Unknown XJ
I've heard to stay away from refurbished pcms. There was one in my XJ and it took a dump before I bought her. Replaced it with one out of another XJ the guy had and she took off.
He told me gettin one that wasn't refurbished is the way to go. Idk how true that is though.
its refurbished but fully renewed and programmed like your original one bought one long time ago for my ford and works fine
they ask for the vin and old pc number to program it as the original one
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Old Sep 27, 2012 | 11:28 AM
  #15  
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Originally Posted by 99purpleXJ
I saw that sellers ad on ebay. Let me know how it works out for you.
when i have the time i well , also i well try to add a video with a moment of truth with first start .

i well try to do it on sunday
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