1G ECU swap 1992 to 1990

[Breau]

Hello I have followed the derections as follow by changing the pt and all the wire pin in the ECM but I am still getting a rev issue help

Today 08:21 AM - permalinkBreau

I have a 90 Talon TSi and have put a 92 ECU into it. it would start but the tach would jump all around, and would not reach high revs and not more than 2000 rpm while in gear. So I searched forums and found that if you changed the power transistor and a couple pins on the computer that it would fix the problem but the car is doing the exact same thing.

Any idea what could still be the issue?

 

[Breau]

can i get some help trying to convert my ecu have changed the pt and ran the wire from pt to pin 109 and switched pin 6 anf 14 but the tac is jumping still and when revving the car it will cut out at 2000 rpm. The colors on my wire harness to the ecu are way difrent colors than any diagram i can find 14 was green with black and 6 was yellow ?

 

[steve]

It sounds like your not firing on all cylinders. Changing the power transistor is only part of that system, the ECU and coil the other two main parts.

The tach signal on a 90 is generated at the coil pack from the coil primaries being pulsed by the power transistor under command from the ECU. Those are combined by the tach gate module attached to the coil bracket and filtered by the noise filter attached to the intake manifold stay before going to the gauge in the cluster.

Since your gauge is jumping around and the engine runs rough, it sounds like your not firing the spark plugs like you should.

Does the engine sound like a lawn mower? That's an indication that you're not firing all the cylinders.

 

[92dsmlunnen]

I am having the same problem. I got a 90 GSX with a 92 FWD ECU.

I switch the pins around and it would still jump so I had to swap out my 90 coil pack with the 92 and still have the problem. Now I have weird idle problems were it wants to idle low some times normal until its warmed up then it idles then it idles high around 12 to 1500 and with surge. It sounds like a little miss when at low rpm and speeds just putting around the street but does fine when I drive then when I hammer on it the tach will read about 4 then work it way down to 0 until I push the clutch in and it will read normal. Any ideas on whats going on?

 

[u2slow]

This worked great for me.

http://www.dsmtuners.com/forums/art...4-ecu-swap-into-1990-dsm-ignition-wiring.html

 

[steve]

can i get some help trying to convert my ecu have changed the pt and ran the wire from pt to pin 109 and switched pin 6 anf 14 but the tac is jumping still and when revving the car it will cut out at 2000 rpm. The colors on my wire harness to the ecu are way difrent colors than any diagram i can find 14 was green with black and 6 was yellow ?

Sounds like your having a problem identifying the correct pins. Have you looked at:
http://www.dsmtuners.com/forums/articles-tuning-ecu/246467-how-identify-ecu-pin-numbers.html

Remember when you look at the front of the yellow connectors pin one is going to be on the right side. The pin hasn't moved only your perspective.

 

[lasershark]

thats why i got rid of my 90 they are just a little different enough to make everything difficult