ECM PCM questions

I have scoured the posts here and online in hopes of finding this info.

I have a 1999 Jeep Cherokee XJ 4WD Automatic 4.0 I6

Part number P56041 493AD (I have low emissions without security feature)

My questions are as follows:

1) Any good online stores to buy a refurbished PCM/ECM? I have talked to a few and considering these guys http://www.fs1inc.com

these guys had some negative reviews in a jeep forum (can't remember which one) www.allcomputerresources.com

2) Should I buy used? Seems like a lot of risk with rare chance of reward.

3) Is there any place that takes the old one and fixes it?

4) It seems hard to do it yourself, especially for the type of ECM I have, is this an option? If so, are there any decent DIY videos? I couldn't find one for my year and type of ECM.


full disclosure: I do not work and am not affiliated with any of the companies mentioned in any way.

Thanks!!!

Jeep PCMs rarely fail, so I'd gamble on a used one from someone parting an XJ out. That said, from your other thread, it sounds like you have a bad sensor. PCMs usually work or don't, not work fine after reset and then run rough once learn bad data from sensors. I blew a PCM once when the upstream o2 sensor harness melted on the back-facing o2 bung on the Borla.

Ok thanks!