07 2.3L cold start = crazy low idle
 

Hi folks.

I bought an 07 3s Touring M/T hatch with ~60k on the clock a little over a week ago. The past couple of days, something unusual is happening when I start the car for the first time in the morning. She starts up fine but the idle is extremely low... I would say around 500 RPM. It's so quiet that I didn't even think the car was on the first time it happened. It's almost as if the engine is about to stall, but instead just hangs out at 500ish. Upon giving the car a little gas, there's a bit of a shake and the tach drops down almost to zero RPM, but then jumps back up to around 2k and resumes normal operation. The only engine mod is an Injen CAI.

I'm coming from a stock 98 Jetta so I have no idea if this is normal. There's no CEL and after that initial uneasiness, she runs great - no rough idle, shaking, uneven acceleration or anything of that sort. The P.O. was on top of all the maintenance and had receipts for everything, including the intake install. I've heard of intakes throwing codes but there is no CEL and the problem only occurs when the car has been sitting overnight.

I plan on bringing the car by the garage my family has been going to for years either tomorrow or Friday, but figure'd I'd ask around here first.

TIA

I have the same issue with my '07 Mazda 3. Did you ever find out why that's happening?

Thanks,
BZ