Hi we have a 99 Cirrus LXi (2.5L V6) with 65k miles, For the last couple years it has a random electrical spike (not sure how to word it) when it happens the rpm / speedometer gauges will flip to max and back and there's a very brief loss of power, the engine light comes on for a few seconds then goes off, the car never dies when this symptom occurs.

We've tried verifying the electrical connections under the hood were clean & tight, cleaned battery terminals, but haven't been able to solve the surge symptom yet, The car runs fine other than this.

We took it in to get smogged recently and although it passes emissions the OBD self test was incomplete which is an automatic fail, they suggested we drive it for a few days with mostly highway miles but when we took it back this morning its still failing the same tests.

I was hoping someone here might have experiance with this surging issue, sometimes it wont happen all day so it's pretty random.

Any idea appreciated!

Not sure if this helps any but heres the results from smog test:

 

I've had the same problem before (once), turns out the terminal connections were loose. Now for your case, have you checked all your "grounds". I might see that as a problem.