90 ecu keep burning

[slow_dsm1]

hi! i have a 1990 plymouth laser,. it ran great and strong for like 4 months with a brand new motor. a week ago tried to start and it wont start, check spark only 1 and 3 fired. check the ecu, it burned. replace a new one, start up right away, run great for like a day.
try to again a very next day, it wont start, turned out the ecu was burn once again. anybody have idea whats going on with my car? please help me!!!
thank you

 

[AWDPetmitsu]

Function check your ISC motor. The steps are here:

http://dmtalon.v8eaters.com/ISC.html

A faulty ISC can ruin the ECU. Where did you get your new ECU from?

 

[slow_dsm1]

The car seems to be idleing ok when it is running but i will have to get a hold of a volt meter to check it. The ECU I got was from one of my friends and it had worked fine before. Both times the ecu burned near the large and small caps in the midle of the ecu, if that helps at all.
thank you.

 

[akdsmer]

Whenever changing out a computer, it's pretty important to check the amp draw of all the solenoid circuits. They should all be under 1.1-1.2 Amps except the Injectors (vehicles that control the coils directly also will exceed this amount. Automotive computers can't handle more than this for any length of time. The reason the injectors and coils can is because they have a very short on-time duration. The idle motor is very common, but any solenoid can short out and cause these problems.

 

[steve]

Both times the ecu burned near the large and small caps in the midle of the ecu, if that helps at all.

That just looks like failure from leaking capacitors and not from something unusual going on with the car.

It is unusual for the leakage to be on that side of the cap because of the way the ECU is mounted in the car but stranger things have happened. Usually in DSMs the leakage flows in the direction of the connector since that's down.

Steve

 

[NickR]

If you figure out this problem let me know, I am having a very similar problem