ecu swap problems?? cels

[mitsubishimanic]

so my ecu fryed and i swapped my ecu now the car idles but dies if givin any gas. it is also throwing cel codes saying my tps and maf are bad. the car ran ok before the ecu fryed any ideas why this would happen. i swapped from a 90 non eprom to a 91 eprom followed the how to in the tech forums. i am very dumb founded only owned the car for a month before the ecu fryed.. any help would be awesome im new dsms and a lil lost.

 

[92ViperRedGST]

This is a very common issue in first gens being that there a resistors on the circuit bored which contain mercury which they like to go bad and leak due to extreme cold weather or really hot weather... the mercury can ruin the other circuit paths on the bored causing a number of issues... i believe the non eprom and eproms are interchangable so ## new ecu may be bad as well.... let me know i got a freshly rebuilt ecu from 92 gst which I know works...

 

[antilag]

Well, the difference in 90 to 91-94 ecu's are pins 6 and 14. They are maf reset and closed throttle switch, which are the codes that you are getting. So, either you swapped the wrong pins, or you actually have a 90 ecu and didn't need to do the swapping of pin 6 and 14.

 

[mitsubishimanic]

code 14 wich is tps and the other i cant remember ill check later when it quits raining but im preety sure it had something to do with the maf.

(edit) it was code 25 barometric pressure sensor or "maf".

 

[antilag]

Did you swap pins 6 and 14 on the ecu harness?

 

[mitsubishimanic]

yes i swapped pins six and fourteen and upgraded the ignition system

 

[steve]

This is a very common issue in first gens being that there a resistors on the circuit bored which contain mercury which they like to go bad and leak due to extreme cold weather or really hot weather... the mercury can ruin the other circuit paths on the bored causing a number of issues...

In the 20 years that I've owned a DSM I've never heard this and in the 10 years of repairing DSM ECUs I've never seen the resistors leak. Where did you dig this up?

The capacitors leak and damage the board but the only issue I've seen with the resistors are the injector snubber resistors over heating.

 

[mitsubishimanic]

ok so any more input would be awesome. has any one ever heard of a car running fine then the ecu frys then getting and installing a new one and now i have cels. they are codes 14 25 which are tps and barometric pressures sensor or "maf".

 

[steve]

There are tests in the FSM for your TPS along with the wiring diagrams. I'd start verifying them as well as checking the ECU since not all replacements are equal. (it could be bad too)