5.3 ECM help
 

My 2002 Avalanche has finally racked up 230,000 miles and even though I haven't had any problems at all, the dependability is questionable. So I'm swapping in another motor and rebuilding the old one to put in my 1974 Jeep J20 baja truck.

My question is can I get a used GM ECM to run the old motor temporarily on either a stand or in the Jeep until I can get a FAST system? I think I can just plug a factory ecm (100 bucks on ebay by the way) into some power and that will get me running enough to check leaks and tolerances after it is rebuilt.

Anybody else running a FAST system? Is it worth the money? Is there a cheap option somebody has done?

Thanks

yea you just have to get the vats turned off and get a decent harness built

Im sorry but what is the vats? do I just take the ecm to a dealership or use a programmer to take it off?

vehicle anti theft system wont crank unless its turned off you can check ebay under say ls1 wiring harness or something and they will cut you a harness and supply you with a computer that is tuned and ready to go or depending on your budget i bought a new harness for a custom app for any vehicle with a tuned computer for around 600 the computers arent really worth alot cause they have to be tuned