Losing power while driving

New to this forum, and already having issues :).

I have an intermittent problem with my 2003 Alero. I sometimes lose power while I'm driving. This issue occurs unexpectedly, and usually in the middle of an otherwise uneventful drive. My car never actually stalls out, but the engine chugs and acceleration fluctuates. No other vehicle functions are affected during this (such as power steering, lighting, etc.). It has occurred 3 times in the past month. The first 2 times the problem lasted just a few seconds (acceleration was lost, regained, lost, regained, lost, then regained and that was it). The last time, however, it lost acceleration and never came back. You could press the gas pedal all the way to the floor and nothing happened. I pulled the car to the side of the road and turned it off. I restarted it again and it was fine for a bit, then lost acceleration again until I turned it off. That time when I restarted it my car still would not accelerate. I left it for few hours, then when I started it again it had no issues. This was 2 days ago. I took my car in to a GM dealer yesterday and they ran a diagnostic and came up with nothing. The only issue was that their diagnostic computer did not recognize my after market stereo. Could this problem be linked to a stereo install issue, or is there another explanation for this? Any help would be appreciated.

:banghead:

Welcome to AF. What engine does your Alero have ? Did They check the fuel pressure? Fuel pump
May be starting to go. Have the fuel regulator checked as well. May not hurt to put a new fuel filter in it .

I have a GL1, with the 2.2L engine. I'm not sure what all they looked at, they only gave me the result (or non-result as the case may be) of the diagnostic. I take it that niether of those things you mentioned would show up on that? Also, are those expensive things to repair?

I would go back and get the fuel pressure checked and regulator checked. not sure where filter is located on these cars but you can Look under car near fuel tank ,see if you can spot a new shiny filter on it. not sure about your stereo issue but how long has it been there ? Just for kicks check your warranty if it`s pump going bad ,5yrs/100,000 km????

Well, it's back in the shop again today. I was driving and the issue occured, worse than before. It actually started feeling like a transmission issue, as the RPM's started going pretty high, and the engine would rev while not accelerating. Oddly enough, still no lights come on the dash.....:banghead:

So I waited until the wife came home from work and drove it to the shop.....with no issues on the way there I should mention. What a frustrating situation.

I mentioned those things to the mechanic, as well as my transmission concerns. Hopefully they can find something this time. It still has the powertrain warranty, but that's it. Hopefully these things are covered under that (and I believe they are).

And the stereo is about 3 weeks old, but I'm really starting to doubt that it has anything to do with it. Most likely the GM mechanic trying to deflect me back because he had no clue what might be wrong.

Well they should be able to scan the engine and trany for any codes. Not likely the stereo if it was doing it before problem started. if not then maybe disconnect it and try it again.