986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - slow rpm drop in neutral and bad gas mileage

ohhh my · 09-22-2012, 11:52 AM

I have an 03 Boxster S.

I'm still trying to figure out what's wrong with my car, I had a bad idle which is almost completely gone after cleaning my throttle body, but sometimes the idle will fluctuate a little.

Lately, I've notice my gas mileage around town to be 5 lower than it usually is with the same type of driving. I'm getting 14-15 when I use to get about 18-19. The highway miles I'm still getting 26 -27. My car threw a P0171 code last week after I cleaned thr throttle body, I cleared it and it hasn't come back since.

When my car is in neutral, and i step on the gas, it seems like the car is taking longer than usual to drop back down to 800rpm.

Thoughts?

09-22-2012, 11:52 AM	#1
ohhh my Registered User Join Date: Jul 2011 Location: so cali Posts: 302	slow rpm drop in neutral and bad gas mileage I have an 03 Boxster S. I'm still trying to figure out what's wrong with my car, I had a bad idle which is almost completely gone after cleaning my throttle body, but sometimes the idle will fluctuate a little. Lately, I've notice my gas mileage around town to be 5 lower than it usually is with the same type of driving. I'm getting 14-15 when I use to get about 18-19. The highway miles I'm still getting 26 -27. My car threw a P0171 code last week after I cleaned thr throttle body, I cleared it and it hasn't come back since. When my car is in neutral, and i step on the gas, it seems like the car is taking longer than usual to drop back down to 800rpm. Thoughts? Last edited by ohhh my; 09-22-2012 at 01:19 PM.