IF you took that BW wire off the top of the engine and didn't gnd it somewhere else, THAT could be your problem. In otherwords you lost part of your ECU's grounding. IF that is what happened.

If it's all back together, you could just pull the plug off that has 3A, 3B, 3C and 3D and with a meter make sure all three are going to gnd. On that plug that is, not the ECU. I know you know better than to look in the jack of the ECU, but..........just to be sure.

 

It sounds to me like this might actually be the problem. It is amazing to me how sesitive these cars are to grounding issues. I guess that is univeral hower. A simple test here in a little while will tell me. I will post this evening. Maybe I will post a wav of the car contentdely idling at a staedy 750 rpm HAH!

 

OK, CHecked the ground on 3a, b, c, d. I am getting a good solid ground on pins c and d (pegs the meter immediately) but a very weak reading on a and b. The meter moves about a fifth of the way up the meter (I am using an old needle type meter) ANyway, it move up the gauge but slowly. I am guessing this is a problem. I guess I need to locate these wires at the firewall and ground them there to the block.

 

Hailers,

Does your 91 Diagram show the wires coming off of 3A, B, C being B or B/W. Mine shows B, but on the harness they are actually BW. This is why I thought that they should not go to ground.

 

IT LIVES!!. Thank you Hailers for sticking with me while we diagnosed this thing. You Rock! After a year of rebuilding, the 89 GTU/TURBO II conversion is ready to roll.

Turns out that the problem was the grounds. All that diagnosis and guessing... ground wires. I grounded the other ECU BW wires on 3A,B,C and it fired right up. After 10 minutes of some serious smoke after the rebuild, she is idling like a kitten. Now to finish it up and drive. Thanks again all! Especially to you Hailers!

 

Hailers is the man! Good work!

 

It shows 3A and 3B as being black/white. It shows 3C as pure black and 3D is brown/black. It's the 1991 FSM someone put online. The wiring diagrams that is. Every few years there seem to be subtle changes to gnd wires.

Have fun.