There is a cut off date on model year where engine management is not an issue; they just want to make sure your car stays under a pollution level at operating temperature. Is this magic number 95? Then if so OBDI can go in the trash?

I’m pretty sure 96 needs OBDII for emission compliance.

 

Most ECu upgrades will not affect emissions. Idle & very low speeds are not really "upgraded" on a chip. Also if your cats are working well, you can do quite a bit & still pass.

On my old M3, it was tuned so well, I passed with out cats on the car.

 

I'm talking about removing OBDI and replacing it with a Motec. Anyone know if this can be done and still pass emission testing due to ECU modification?

I know you can't do it with OBDII cars, but how about 95's?

 

Depends on if they're looking for OE. What's the standard in AZ now? In the '80's when I was here, all that mattered was passing, and a simple look to see if the cat was there and maybe the air pump. (The mirror under middle of the car looking for a cat on a 911 was always an amusing experience.)

In CA I can't see how you'd get someone to look the other way these days. If you're resourceful, you could certainly make the harness look stock and no one would be looking at the non-factory ECU under the seat.