I have a 1995 Eclipse and the computer died on it. The mechanic I took it into found a used ECU for me, and it worked fine. However, now my check engine light is stuck on. It's some sort of emissions code and every time it's cleared it comes right back on. I'm guessing that the car that the computer came from was eqquipped with an EGR valve, where my car did not come with one at all. Do you guys think there is any way I can trick my ECU into thinking I have an egr valve? Like sending the right voltage to the right circuit or something? I want to sell my car but I don't think I can very easily with a CEL stuck on :(

Anything that can point me in the direction of some help would be greatly appreciated! Thanks! (if you need any numbers or something to see which exact ECU I have, just ask and I'll look for them, it's raining right now though heh)

Originally posted by Wile
I have a 1995 Eclipse and the computer died on it. The mechanic I took it into found a used ECU for me, and it worked fine. However, now my check engine light is stuck on. It's some sort of emissions code and every time it's cleared it comes right back on. I'm guessing that the car that the computer came from was eqquipped with an EGR valve, where my car did not come with one at all. Do you guys think there is any way I can trick my ECU into thinking I have an egr valve? Like sending the right voltage to the right circuit or something? I want to sell my car but I don't think I can very easily with a CEL stuck on :( Anything that can point me in the direction of some help would be greatly appreciated! Thanks! (if you need any numbers or something to see which exact ECU I have, just ask and I'll look for them, it's raining right now though heh)

I've read around on different threads about the useage of a 'resistor' in the connector of the solenoid, in order to not have a CEL on. However, most of the time, members here have the CEL on because they have the whole EGR pipe blocked off with plates... if you do not know a whole lot about your car, you could possibly have it blocked; perhaps from a previous owner. The only positive result from a blocked off EGR is keeping your intake manifold clean of gunk, from the hot gases that are recirculated into it...

For more information about the resistor:
http://forums.2gnt.com/dcboard.php?az=show_topic&forum=4&topic_id=74140&mode=full

your car should have an egr on it.
are you sure your not talking about the pulsed secondary injection system. If its that there is a recall that can be preformed to reflash the ecu to remove the checking for that system.

and there are 2 codes for the egr system which one do you get??

If its for egr system failure a simple resistor in the solenoid seems to work for most.

If its for insufficient egr flow there is no way to fake that one.
(The o2 sensor goes lean for a second during egr operation and the ecu looks for that.) unless you can hook up a relay with a resistor to go inline with the o2 sensor to drop the voltage slightly during supposed egr operation. I have no idea what size resistor though.
Someone with a datalogger could probably tell you how much o2 voltage drops during egr operation.

you can fool both codes, search for the answers.

I called the dealership and couldn't exactly understand what he said, but it sounded something like: dtc 412 and he said it had something to do with my car not being equipped with a pursar solenoid or something. I'm really completely lost now haha. Is there anywhere I can read about DSM ECUS and how to reflash them or what the error codes mean?

Originally posted by Wile
There's a small pipe coming off my headers and it just has a cap on it. So I figure that's where the egr valve might have been. Anyway, my old ECU was completely fine with not having an EGR valve. Is there any way I can get the exact CEL code without paying another $50 to take it in and be read by the dealer?

That's not the EGR, that's the pulsed secondary air injection system. 95's werte the only ones that had it, and the TSB for the system basically says, "If it fails, remove it and reflash the ECU to ignore the fact its not there."

and fyi its a chrysler computer..not mitsu, just incase you might make the mistake of thinkin all DSM computers are alike

Does anyone know what that code is??? 412

dude it was just answered above....
just go the dealer and have them reflash your ECU. that will take care of it.

P0412 ? Or is that some misinterprted CEL blink code?