Ecu?

[TommyDSM]

I purchased a 90 Eagle Talon TSI AWD 5Spd. My Tach doesn't work and when I connect my TMO, I have a Detonation Sensor Error. I checked my ECU to see if it had EPROM, which it doesn't. I thought all 1990 Cars had the EPROMS. If the cars ECU had been replaced with a ECU from a 91+ Car would that cause the Tach not to work and the Knock sensor not to work either?

 

[TommyDSM]

Bump?

 

[slodsm]

I am pretty sure that the car would not run with a 91 ECU, it will but not good. I melted my ECU in my 91 about a week ago and when I threw in a 90 just to get around till the 91 was repaired, it idled at 3k, sputtered every 4-5 seconds, and didn't run worth a crap. The knock warning light is probably fromt he Boots Control Selenoid being disconnected. Not sure about the tach though, sorry I can't be of anymore help.

 

[phastalon]

As far as I know, the harnesses on the 90 ecu's are different than the harnesses on the 91+. Not all 90's have an eprom, mine didn't...but it's not anything you can't buy. Check the trader, I got mine with the TMO stage 3 chip already in it for a reasonable price. If you have a 90 model car, then only use a 90 model ecu. Hope that helps.

 

[TommyDSM]

The car I purchased has a Galant VR4 Engine in it. Since the Galant VR4 is a 91 Shouldn't I upgrade to a 91 ECU? Could the Knock Sensor be bad? And cause the Detonation Sensor error? What do I need to upgrade the ECU, change the whole wiring?