Damaged ECU?

[Redneck Wolf]

Yesterday, my alternator went out.Picked up a new one today, and now my check engine light comes on randomly, and my tachometer is all over the place. I went and got the new alternator tested, as well as the battery, everything is fine. So I was wondering, could it be something in the ECU? or could it be something simple, like a damaged sensor?

[BSOD2600]

Find out what codes are stored: http://legacycentral.org/library/literature/codes.htm then clear them and wait to see what comes back. THEN start troubleshooting the problem(s).

[Jessekrs123]

Sounds like a similar issue I had.

My tach would go crazy sometimes, and my car would randomly shut off.

It turned out to be the ECU ground in my engine bay was loose. Found a new home for it, snugged it up with a bolt and I have not had the problem since.

[Legacy777]

The ECU ground is located on the back of the intake manifold on the driver's side. You can see it in this pic.

http://main.experiencetherave.com/subar ... G_4042.JPG