RPMs are dropping randomly

[h2opololea]

Hi All - I'm hoping someone can give me some help diagnosing my engine problem. I have a 2003 P5 with 88k miles that I just bought a few days ago. No accidents on the CarFax and the last owner installed a high performance air filter and muffler to give the horsepower a little kick. I already love the car (and will most likely stay with Mazda for life), but there's a few issues I need to address to get it running like new.

My engine issue appears to be random and occurs at various speeds (from 0MPH to 60MPH) and doesn't seem to be associated with giving the car gas, using the clutch or braking. I'll keep an eye on it, but my initial observations don't associate it with anything in particular. The issue is that, while driving or idling, the RPMs drop about 800-1000RPMs. When I'm idling the car almost stalls. After a few seconds the RPMs come back up and it seems fine. It first happened when I was going 50MPH, but since then has happened at nearly all speeds. Could this be a coil problem? Something with the EGR? I'd like to fix this before I stall out in a problem area. Just FYI: the car hasn't stalled yet, I'm just worried it will.

Any help is appreciated! Thanks!

 

[hurleyblink]

yes do the egr fix its not hard at all 2 bolts and a plug, also goto autozone grab a can of "mass air flow sensor cleaner" <- only use this specific spray. and spray you mass air flow sensor while your at it you will probably cure your problem.