Recent content by melsman

Thanks for the replies, guys. I appreciate it. The good news is, I solved the problem! I stumbled across some threads that mentioned the high idle and pulsing RPMs on deceleration, and connected this behavior with adjustment of the Throttle Position Screw (TPS), which I had "adjusted" early...

I've been driving myself crazy trying to figure out why my daughter's P5 idled at 1500 rpm and would pulse (or surge, or jump around, or go up and down) on deceleration. After finding that turning the air adjustment screw (AAS) all the way in had no effect (still high idle), and checking for...

Howdy All, First -thank you for the responses. I ended up buying a "rebuilt" PCM from GoECM.com (nice folks) and the dealer was able to reprogram/update this one. But when the car started... the high idle and fluctuating deceleration was back just like before! So, I had them run additional...

Progress so far.... The PCM contains the VIN and current mileage of the vehicle, plus other pertinent hard-written data, so just dropping in an ECU (PCM) from another vehicle may allow it to run, but when scanned for smog and other issues, the VINs won't match, causing other issues. Anyway, I...

Hello All, After finally getting my daughter's P5 running well (see thread here), after about 100 miles, it started back with a high idle (only 1500 RPM this time) and a new twist - an RPM fluctuation on deceleration. This thing is driving me crazy! So, double checked for vacuum leaks and...

Problem Solved!!! - Bad "new aftermarket" Idle Air Control valve (IAC) We replaced the "new" aftermarket IAC with a genuine Mazda IAC (FSN5-20-660B) and the problem has been solved. In fact, the car runs very smoothly in all aspects now. When I pulled the the aftermarket IAC and compared it...

First of all, thank you for the replies! I appreciate it. @pcb - Yes; We ran it for 100+ miles over a couple of weeks and still the same issue. I also reset (again) using the prescribed PCM reset method from the shop manual. Everything works great... except for this dang 3000 rpm thing...

UPDATE *** Replaced the "new" IAC with a genuine Mazda IAC (part #FSN5-20-660B) and the car now idles just as it is supposed to in all phases. No more racing to 3000 rpm! Car now runs great! Just goes to show you that some aftermarket parts, though they say they are OEM replacements (and even...