Flashing an ECM - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Flashing an ECM

FS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectJKS Now Available at www.baseline4x4.com, Trackbars, SkidsFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye Kit

Reply
Unread 03-05-2013, 01:25 PM   #1
vadslram
Registered User
1990 YJ Wrangler 
 
Join Date: Jan 2006
Location: VA Beach
Posts: 4,655
Flashing an ECM

I read through a couple of EFI threads and never saw anything about reflashing the computer. But right now I'm contemplating switching out the ECM on my daughters 97 sunfire GT. Every source says that it will need to be flashed in order to work. How can you pull a GM ECM off of a chevy and assume it will work on a 4.2 Jeep.

Has anyone ever dealt with reflashing and is the only option going to a GM dealer?

vadslram is offline   Reply With Quote
Unread 03-05-2013, 01:49 PM   #2
Reddy89
Registered User
1989 YJ Wrangler 
 
Join Date: Jun 2010
Location: , NJ
Posts: 346
The GM swap has worked because they're coming from 4.3L engines which are similar enough to not require reprogramming.
Reddy89 is offline   Reply With Quote
Unread 03-05-2013, 02:46 PM   #3
Berniebikes
Registered User
1988 YJ Wrangler 
 
Join Date: May 2010
Location: Williamsburg, VA
Posts: 725
More than you want to know about chip programming is over on Binder Planet. You can buy most everything from Moates, or make your own....depends on what you want to do. Go here
http://www.binderplanet.com/forums/s...502#post752502

A tune from a 4.3 will work pretty well on the 4.2, but you may need to make some adjustments. In my case all the numbers from the run file looked good but I made a slight adjustment to the fuel pressure and things were pretty balanced after that. If it is really off, there are also any number of companies out there that will take a run file from you and then burn you a tune to correct what they see on the run file for about $100. If you want a custom tune, that is they give you one tune, then you run it, they tweak it and so on until you are satisfied with the results, there are several companies out there that will do that work for about $300 or so.
Berniebikes is offline   Reply With Quote
Unread 03-05-2013, 08:49 PM   #4
SnowdogMarc
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2008
Location: Alberta
Posts: 1,323
Don't forget that many of the 90's GM computers had a pesky little security thing called VATS....you take the computer out of the GM and drop it in the Jeep without having the rest of the system and it wont even start. I had that issue with my 4.3 swap and had to get it reflashed to remove it and a few other things.
__________________
l We're here for a good time. Not a long time. So have a good time the sun can't shine every day.
l_______
/l ,[_____],
l---L -[]lllllll[]-

()_) ()_)--o-)_)____________VE6-SDG
SnowdogMarc is offline   Reply With Quote
Unread 03-06-2013, 05:32 AM   #5
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 14,969
On the 4.2L or did you mean a 4.0L? The ECU from the Chevy on a Jeep? More info please. I thought I had seen and done all that could be done electrical and now something new! The Chrysler ECU is not flashable for all practicle purposes.
Que89YJ is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.