Computer is the same but the chip is different but it can be used on a manual transmission. I did it. You have to cut one wire from the ECM. Wire B10. This is an input for the automatic that is not used on the manual. If you do not cut it you get a check engine light after the engine has been run for a lenght of time and the engine will run slightly rough. Took me a long time to figure this one out when I did my conversion.
------------------ Rodney Dickman
Fiero Parts And Acc's Web Page: www.rodneydickman.com Rodney Dickman's Fiero accessories 7604 Treeview Drive Caledonia, WI 53108 Phone/Fax (262) 835-9575
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09:14 AM
Rodney Member
Posts: 4715 From: Caledonia, WI USA Registered: Feb 2000
I used my automatic wiring harnesses also on my 88 V-6. I looked at the wiring harness diagrams in the Helm manual and cut and spliced as needed to make everything work. I left in the automatic steering column so I don't have that annoying lever to push to get the key out. No neutral switch so I can start it without putting the clutch in. No up shift light. My cruise works. I had to add a switch and a few wires to make that work.
------------------ Rodney Dickman
Fiero Parts And Acc's Web Page: www.rodneydickman.com Rodney Dickman's Fiero accessories 7604 Treeview Drive Caledonia, WI 53108 Phone/Fax (262) 835-9575
A bit more info: When used for the manual car the programming in the chip runs the shift light, when used in the automatic the programming uses the same output from the ECM to lock the torque converter. If you use the manual chip in an automatic the torque converter will lock at odd and unpredictable times and probably never lock when cruising which is where it needs to lock the most. If you use the automatic chip in the manual car the shift light will come on at most cruising speeds, assuming there's a bulb in the socket that is. There may be some other differences with timing, plus the idle speed target is probably handled differently between the two.
if you can;t work out the ecm, I can probably burn you a chip, but it would be for an 88 5sp, which should not be an issue. I just need to pick up a couple of eproms. I have the stock 88, which has no rev limiter set, and I think I can put one in if you want it. the base ecm should be the same between 87 and 88.
Let me know how you make out. I will need some time to put it together and test one. worst case is driving around with the auto ecm and living with a possible check engine light!
