Idle RPM and MAF - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Mike689 · 08-07-2015, 04:36 PM

I can't find the exact idle rpm for my Boxster S 3.2L. Does anyone know what the spec is? I might be having some trouble with the idle rpm. I used an OBD2 adapter to read the rpm when the engine was cold. It started at 1000 rpm and dropped to about 870 in a minute. I drove the car about 30 minutes and then got 680 at idle. The MAF was at 3.5 g/s at operating temp, which I think is normal?

I'm going to clean the throttle body this weekend is that all I should do?

JayG · 08-07-2015, 06:08 PM

that seems pretty normal to me

Mine starts around 1000 - 1100 and drops to 850ish in about a minute. once warmed up depends if the AC is on or not at idle, maybe around 700 with AC on

Mike689 · 08-07-2015, 07:40 PM

Thanks I guess I was paranoid. Is the the maf ok?

thstone · 08-07-2015, 08:34 PM

What problem are you trying to solve? Is the idle hunting or rough? Something else?

Quick way to test the MAF is to disconnect the electrical connection to the MAF, then start and test drive the car (it won't hurt the engine to drive it this way for a short test drive). If the problem is gone, then it was the MAF. If the problem is still there, then its not the MAF. Quick, easy, and free.

Mike689 · 08-07-2015, 08:41 PM

Quote:

Originally Posted by thstone

What problem are you trying to solve? Is the idle hunting or rough? Something else?

My gas mileage is low and I'm trying to figure out what it could be. I read that cleaning the throttle body could help with mpg and a way to diagnose it is by monitoring the idle rpm. I thought it was strange that the rpm would would go from 1000 to rpm.

I also read about the MAF and that cleaning or replacing it would help with the gas mileage.