Loyale ECU / check engine light

[mcrae0104]

How difficult is it to swap out an ECU? Are they interchangeable on Loyales?

 

Mechanic says mine is spitting out bogus codes (wish I had asked him for the codes). Engine runs same as always--maybe a wee tad rough at idle, but not enough for me to do anything about it given its 188k mi.

 

The ECU is a dealer-only part, laughably expensive, and they say there are multiple versions of ECUs, even within my '91 model--but I still wonder if it could just be swapped out with "any old" Loyale ECU without consequence.

 

Right now I have elec. tape over the check engine light (think it runs even better that way ).

 

I see one for sale over here--http://www.ultimatesubaru.org/forum/showthread.php?t=105278&page=5--wonder if I should give it a try or if it might screw something else up.

 

I have no idea what to offer/what a used part like this is typically worth--suggestions? (bearing in mind that the electrical tape is cheap and it works!)

[GeneralDisorder]

Any 90 to 94 ECU that comes from a car with the same transmission type (auto/manual) will work just fine. The SPFI system is very simple. Even an ECU from an '87 to '89 with the same tranny type should work fine though there there are some slight differences between 87-89 and 90-94.

 

But an ECU failure is basically unheard of. I would quesion their diagnosis. I have heard of maybe one or two failures in all my years here and those were due to people hooking up the battery backwards and blowing the power supply circuits in them.

 

GD

[Cougar]

I would be suspicious of replacing the ECU also. They can have problems but it isn't very often. I would first make sure the power to the ECU is ok before saying it is bad. Make sure that there isn't any AC voltage coming from the alternator. The AC voltage should be no more than .1 volt with the engine running around 2000 RPM.

 

If you do need a ECU you can get rebuilt ones for about half the cost of a new one. One from a salvage yard may run you about 50 dollars.

[mcrae0104]

Thanks all--think I'll get it re-checked.