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Steve Tinker · 02-06-2014, 06:35 PM

Something doesn't add up here - you say that when the rpm is stuck (open I ssume) you are seeng air flow across the MAF but the throttle position is closed at the same time!!

(I'm playing devils advocate here). If thats the case, then air flow is passing the (supposedly) closed throttle body - which isn't fully closed as the engine would not run at high revs with the it fully closed. So could there be a problem with the throttle body (I know you've checked, but..)?

I'm also assuming that fuel delivery is controlled by the throttle body position, so if it is sticking open you will still get fuel through the plennum. If its not sticking open, hows the fuel entering the engine ???
Can you check your fuel trims when this problem occurs.

02-06-2014, 06:35 PM	#34
Steve Tinker Registered User Join Date: Dec 2008 Location: Queensland, Australia Posts: 1,522	Something doesn't add up here - you say that when the rpm is stuck (open I ssume) you are seeng air flow across the MAF but the throttle position is closed at the same time!! (I'm playing devils advocate here). If thats the case, then air flow is passing the (supposedly) closed throttle body - which isn't fully closed as the engine would not run at high revs with the it fully closed. So could there be a problem with the throttle body (I know you've checked, but..)? I'm also assuming that fuel delivery is controlled by the throttle body position, so if it is sticking open you will still get fuel through the plennum. If its not sticking open, hows the fuel entering the engine ??? Can you check your fuel trims when this problem occurs. __________________ 2001 Boxster S (triple black). Sleeping easier with LN Engineering/Flat 6 IMS upgrade, low temp thermostat & underspeed pulley. 2001 MV Agusta F4.