PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

swapping PCM's

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Old Sep 3, 2015 | 01:37 PM
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Default swapping PCM's

I've got a 98 pcm and harness that the ECM is not reading bank 1 sensor1 02 inputs.

I got a second 98 PCM by the grace of god on the cheap, but I dont know if its a manual or an auto...I have a manual.

My car runs on a stand alone harness since it was a v6 swap, so vats and the usuals wont matter. I have HP tuners but I'm still learning with it. I know I can take my tune and write it to the new ECM, but will it matter if that PCM is from a auto?

thanks
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Old Sep 3, 2015 | 01:45 PM
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Save the current tune on the car.

Install the new PCM and "read" it, Then license it.

open your old tune and while connected to the car do a "write entire" and overide whatever tune is in the PCM with your original tune you want to keep..
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Old Sep 3, 2015 | 01:49 PM
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Perfect thanks
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Old Sep 3, 2015 | 01:52 PM
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Originally Posted by blackbyrd
Perfect thanks
just make sure your car battery and laptop are charged so they don't die during the "flash"

The 98 pcm's are know to brick/freeze permanently if power is lost during a write entire
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Old Sep 3, 2015 | 01:56 PM
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will do

even if it doesnt work it was $25 and I have a 99+ ecm i got for free but I really didnt want to go through repinning the harness. I still have enough credits to unlock one more PCM. Even though I ruled out everything I could think of thats causing the issue this will tell me for sure if its still not reading the 02 sensor.
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Old Sep 3, 2015 | 02:02 PM
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Originally Posted by blackbyrd
will do even if it doesnt work it was $25 and I have a 99+ ecm i got for free but I really didnt want to go through repinning the harness. I still have enough credits to unlock one more PCM. Even though I ruled out everything I could think of thats causing the issue this will tell me for sure if its still not reading the 02 sensor.
ah I see

Well re pinning isn't that bad if you have to do it..

I did it on my 98 car, basically a 2-4 hr job labeling everything and plugging it in elsewhere
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Old Sep 3, 2015 | 02:42 PM
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yeah I have everything to do it but my harness is actually inside the car under the passenger dash instead of the engine bay. I was dreading doing it and a batch of 98 ECM's literally 15 minutes from my house popped up on a local sales forum.

I was prepared to do the repin till these popped up, it would probably drive me crazy if I went through repinning and still had the same issue in the end. So testing the 98 will at the very least put that to bed.

Thanks for the info and help though
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Old Sep 3, 2015 | 03:42 PM
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Originally Posted by blackbyrd
yeah I have everything to do it but my harness is actually inside the car under the passenger dash instead of the engine bay. I was dreading doing it and a batch of 98 ECM's literally 15 minutes from my house popped up on a local sales forum. I was prepared to do the repin till these popped up, it would probably drive me crazy if I went through repinning and still had the same issue in the end. So testing the 98 will at the very least put that to bed. Thanks for the info and help though
No problem.
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Old Oct 10, 2015 | 09:14 AM
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Hello all
Today I believe my ecm took a leave of absence since the main power was interrupted during working on truck with key on. (Not sure why) key was on. Now my fuel pump relay is chattering. I checked all wires. Disconnected fuel pump. Still chatters. Cut the feed from ecm. Stops chattering. Supply 12 v an relay works. Fuel pump pumps. I am guessing that the Ecm got screwed up when wire got disconnect with key on. Obd2 port don't work as well as with fuel pump on it won't start..

If I get Ecm with same vin # will I have to still use credits to download tune from hp tuners?
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Old Oct 10, 2015 | 10:23 AM
  #10  
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Default Pcm

If I have a pcm programmed to my vin number will I still be able to use tune from hp tuner without using credits
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