Hello everyone,

My 1999 engine seized due to an oil leak, ended up swapping in a 1997 engine. Everything went relatively smoothly except for an extra digital EGR sensor on the '99 but not on the '97. Now there is a CEL, I want to get rid of this problem and try to pass smog by swapping for a pre-'99 ECU. I'm curious if the harness across the years are the same.

Is there any foreseeable issues (immobilizer) or is it just a simple plug and play swap out. The swapped engine is running decently but I want that CEL gone.

Best Regards,
J

 

It would be a great deal easier to simply install the 99 EGR system on the 97 engine. The engine harness on the 99 vs. 97 is a little different. Not worth the effort in my opinion.

 

This!

 

it would be a real pain to convert your 99 into a 97 ecu due to the NATS. Just swap out the manual egr valve for the electronic one of your original engine and be done with it.

Did you swap over the evap lines and those solenoids that go with it? did you swap over the lower intake manifold with the butterfly valves or are you running all 97 stock parts with a laundry list of cel codes?

when i swap motors into a 99 with a motor pre-99, i swap out only the long block and use the other parts original from the car that way there are no cel codes to deal with.

 

Not the point of the thread, but you're wrong, just pointing that out.