I have a 92 grand prix. Out of nowhere when I hit my breaks the car would sputter & eventually die. So I had my break booster replaced & now not only does it still sputter it’s has a lack of power when accelerating & I can smell a little oil burning. It hasn’t stalled but it sure isn’t running smooth. Is the booster bad? Do I just need a new air filter. I’ve haven’t seen any leaks & the breaks work fine so I don’t think it’s the master cylinder. Any help…?
I’d have guess the booster was the problem too, based on the original symptom. But that’s been replaced and now it not only sputters when you apply the brakes, you’ve lost power during accelerations when no brake are even applied? hmmm … this is a tough one …
Well, maybe the engine was just running poorly & you noticed it more at idle rpm with your foot on the brakes and the car still in gear. This is an automatic, right? That’s a pretty common thing reported here w/automatics. B/c the engine is trying to make the car move and the automatic is holding it back, you’ve got some load on the engine at idle rpm. Subtle engine problems will show up in spades w/that sometimes.
The booster can be eliminated as a cause probably by clamping it off temporarily. Don’t try this yourself b/c the brakes might not work with the booster clamped off. But a tech could try it in the shop to see if it has any effect. Based on what you say, I doubt that’s the problem. Still, worth a try as it is quick and easy to do.
What’s the situation with the routine engine maintenance? Is anything past due? If so, that’s probably the first place to start. And getting the codes read. Note that there may be stored codes even if the CEL is not on.