*update* new ECU install... strange, strange things.

[sytrus]

alright so my problem from a couple of days ago (car shut off while running), turns out the caps on my ECU were leaking. It was a 1990 ecu anyway, in a 1991.

I got the 1991 ECU today, everything was perfect on the inside.

Installed it, and now it is doing very strange things.

I started it up....and it sat at 1500 RPMs I was pumped up that the problem had been solved. Then it started to stumble at idle... it sounded like it was almost going to stall several times. T

then it started to "rev" itself. The RPMS would jump from 1000 to 1500, over, and over, and over. Then go back to the stumbly idle.

Anyone know if this is normal? Or if it is a problem what it could be?

 

[jsteele90]

is it a new ecu or just new to you if so then the caps could have leaked and been replaced but still damaged the circuit board beneath it . being as the section that controls the isc is n the area that usually gets fried

 

[sytrus]

it was rebuilt by the manufacturer i believe, and i looked there already... there is no noticeable damage.

 

[jsteele90]

doesnt the ecu wiring have to be changed when switching to a 91 ecu in a 90 ? and since you switched back to the correct ecu ???? is there any wires spliced in on your ecu harness that are not factory??

 

[onegee]

Its probably Idle surge, might not be due to the ECU.

Search the term:

http://www.dsmtuners.com/forums/search.php?searchid=440175

Look thru those threads.

Heres one from Brad Bauers old page:

http://web.archive.org/web/20030212125356/myzero.com/engine/surge.html


Good luck .

 

[onegee]

doesnt the ecu wiring have to be changed when switching to a 91 ecu in a 90 ? and since you switched back to the correct ecu ???? is there any wires spliced in on your ecu harness that are not factory??

Just read your first thread you posted. I'd try what jsteele90 said.

 

[sytrus]

yea after thinking about it... we had to splice a wire over.. so we're just gonna undo that, and see if it works.

Because when we isntalled the 1990 ecu, it was having the EXACT same problems. So, hopefully that works.

THANKS GUYS!

 

[steve]

Just in case people don't know, you don't have to cut and splice wires to swap the pins. They pop out of the connector easily if you use a jewlers screwdriver to gently lift the pin retainer. The FSM shows you how to release the pins from the connectors.

Steve