Hi folks. I'm having a bugger of a time trying to figure this out. Here's the deal...

I recently installed a remote start/alarm system on my 2003 WRX 5spd. Right away weird behavior started. When I start the car cold (morning & after work) with the remote or with the key it jumps up to a high idle at about 1200rpm and throbs up and down. It has terrible throttle response and jerks and stutters at low throttle inputs but tends to smooth out with more gas. After driving for several minutes and the engine gets nice and hot, I can shut the car down and restart immed. and it will go right to its normal idle at around 500rpm and drive perfectly. It will stay fine like this for the rest of the day as long as it doesn't sit for more than a few hours, in which the crappy behavior returns.

Of course I assumed this was somehow related to my recent installation so I had a pro check it out and he said it was all good. I finally broke down and took it to the dealer to put it on the computer and they said I had a bad MAF sensor - they said this can happen from the oil on aftermarket air filters burning out the sensor pin (I run a Green drop-in). Well its a good thing I didn't run right out and drop $175 on a new MAF because my brother has a WRX also and I swapped his MAF sensor in with the same results.

I really don't know what to do and none of my local people that I usually rely on have any real advice. Can someone point me in the right direction for where to look to fix this? Has anyone heard of this behavior before?

Many Thanks in advance...

-Mike