I was on madz28 and saw he had a retrokit setup to swap your obdII pcm for an obdI pcm.....I was confused at why you would want to do such a thing. Is the obdI pcm better? I'm a newb so thanks for your time--

 

Sometimes with a high stall converter OBD1 can get confused and go into limp mode, madz28 has not figured out a software fix for it so he recommends a swap to OBD2 to avoid it. Other tuners have figured out software fixes for it and actually sell a lot of OBD1 pcms to OBD2 car owners because the OBD1 is much cheaper to tune and log yourself. In my car I used pcmforless.com and swapped from OBD2 to OBD1 and bought all the tuning and logging stuff. I let pcmforless make all my major tuning changes and just give it little tweaks myself. I never had the OBD1 high stall issue but then again when I got the converter I had Bryan do an update for me to cover it, a friend neglected getting his updated though and he did have the high stall limp mode problem till he contaced Byan and got his tuning updated for the new mod.

Don't take this as a knock on madz28, I did some other buissiness with him and it went very well.

 

Just for the record... there is no such thing as "limp mode" in our cars.

 

Thanks guys, I think I am just going to stick with the obdII that came with my car Luckily I have a 6 spd and not an automatic!!!

 

How do you figure? Maybe we are just using differnt definitions of limp mode.

 

Every article I have ever read on GM computer control systems describe the "limp" mode. It is not what everyone thinks it is, and few people actually experience it, but it does exist.

 

Eh, maybe I'm wrong... I thought I read on a post on here from someone pretty reputable that there was no such thing.

 

Depending on what is going on you can lose gear selection in the tranny and enter speed density with the fans running full time. Usually happens when the pcm believes it is seeing false info from sensors so it goes to running off of preset "safe" settings.

 

I second the existence of a "limp mode" My car went into it when I threw an EST ground code. Ses light came on, fans came on, car had no power and tranny shifted like crap, overall the car was functional but just barely. I have thrown this code twice and both times the car went into this "limp mode". It has never done it for any other code.