Ok I am still pretty new to the site. I have searched to forums and I can't seem to find an answer to my question. If it is out there just let me know. I just need to know if the computer out of a 87.5 2.9 will work in a 91 2.9. I am having issues with a truck I just bought and my brother have a parts truck. The problem is this I try to start the truck and it takes about 7-10 pulls to get it going them it idles rough and sometimes dies. When it does run it realy hesitates when I try to accelerate mostly just on take off. It runs best between 2ooo and 3ooo rpms. It sometimes is worse then other times. I have run codes several times and I get engine temp sensor out of range and whatever the problem is that relates to idle air control valve(replaced and code dropped). The temp sensor however hase been changed twice now witch if you have done this you will realize is kind of a pain and it still runs the same code and the truck runs no better. So that is what leads me to believe there is a problem in the computer. I found burnt flatwire when I opened the comp(because b4 it was throwing codes that said the comp was out of whack and wouldn't go into test mode without me bridging test circuit to negitive on battery on KoEr test) but I resoldered it and I pull double 11's on the KoEr test now. Anyway does anyone have any idea whats going on here and if the computers are enterchangable on these 2 years of the same engine.