[b3lha]

Originally Posted by TomsSVX

Absolutely true... I put a 94 ECU into my 92 a couple years ago and came up with the EGR Temp sensor code... Had to change it out to a 92 ECU The temp sensor doesn't change anything, it merely detect when the EGR is open/closed by detecting the heat. So there are no extra ponies laying up in there

Tom

OK. Thanks Tom. That's more interesting info for me to research. I thought that the ECU "commanded" the EGR when to open/close rather than "detected" when it was open/closed.

I seem to remember that the 92 ECU, when operating in california mode, does some extra calculation in the section that processes the reading from the O2 sensors and also in the section that controls the AFR learning cycle. Could it be that the EGR system introduces some kind of error into the O2 sensor readings that must be compensated for?