I had to replace my ecu on my 91 z28 305 tpi and I'm having trouble getting it to idle. My manual says that I have to use a scan tool and relearn the idle. Is there any way around this or am I going to have to get a scan tool and relearn the idle? The manual also said this could be cause my code 43 which is the ESC. I replaced the knock sensor but no change in the code or idle even after I reset codes.

 

There is also a flat square box maybe on the left side of the firewall bt the brake booster. The knock sensor works through it.
But a few drive and ignition cycles should take care of the relearn. At idle the computer can not run through all its tests.

 

Alright man I appreciate the tips. I was worried I was goign to have to buy a scan tool lol

 

alright after talking to some friends about this... they said that it sounds like the esc. I go to the autozone website to see how much one will cost, and apparently my car doesn't have one. Right now the car acts like its carbuerated. I have to give it gas to get it to start or idle until it warms up. once warmed up... it idles and runs just fine. I can't think of whats wrong... maybe the ignition control module? Then again I have never driven the car... spent two months working on it then come to find out Im having a pain in the *** getting the title in my name.

 

a easy way to test ur esc is with your car running look for a little plug just wire to wire near ontop of ur psngr side wheel between strut and firewall or even a unplugged connector that should be ur esc connector if it is connected wire to wire as should be disconect with car running and car should run lower or more like crap if not connected when connected car should run alot better or as it should this connector is used to set cars initial timing only my wire is red with blk cylindrical connector if u cannot find u might want search inside of the harness protection cover to see if some 1 stuffed it to hide it and connect it.

 

u want the wire thats tan with a black stripe with a cylinder connector not the red wire there both in the same area but te red 1 is rubber and the correct 1 is a plastic clip connector.

 

I know what wire you are talking about, but I just disregarded it as an option my car didn't have because there doesn't appear to be any wires to connect to it. Should there just be another wire close by to connect to it?

 

Did you think about replacing the IAC (idle air contol) valve. That is what conrolls the Idle on TPI car.

 

I also havent tracked the whole route of that line yet myself im sure that wire is apart of harness and inside the protector tubes im guessing that 1 place u should find it at is the relay area at the firewall drvr sd there should be either a a little electric black box it might even go into the firewall connector harness possibly to the comp thats just 2 random possiblilties for a start. For the wire ending should probably be at the actual distributor at least by concept the the use of the wire and connector is strictly for base line setting of engine or reseting baseline it either lets computer controled timing plugged in or all around driving and unplugged only for raw engine timing no timing advance just for setting.

also do not know if its a comp to comp disable loop wire only know the purpose where to find it and what it does for me to find route would consist of me gutting my harness beyond belief.