986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - How to diagnose and resolve engine issues using Durametric.

jb92563 · 05-11-2014, 10:39 PM

Found some free online Porsche workshop manuals
http://workshop-manuals.com/porsche/

I'll be compiling my results and putting together an explanation, but in short for now I found that the RKAT fuel trim was elevated, indicating that the computer is adding extra fuel to compensate for a lean condition, which could be caused by:

- Intake air leak
- low fuel pressure
- exhaust manifold air leak

since the car was running fine prior to my AOS issue it was most likely to be the intake air leak so I loosened and retightened all the intake tube clamps and removed and reattached the upper AOS to intake tube.

the value of RKAT is reduced slightly but the car seems to be running fine, so i'll drive it this week and see if anything further develops.

in the mean time I ordered new fuel cap, spark plugs and fuel filter as these items are due at 70k miles and can only improve the current situation.

more to follow as things progress this week.

05-11-2014, 10:39 PM	#9
jb92563 Registered User Join Date: Apr 2012 Location: Riverside, CA Posts: 1,665	Found some free online Porsche workshop manuals http://workshop-manuals.com/porsche/ I'll be compiling my results and putting together an explanation, but in short for now I found that the RKAT fuel trim was elevated, indicating that the computer is adding extra fuel to compensate for a lean condition, which could be caused by: - Intake air leak - low fuel pressure - exhaust manifold air leak since the car was running fine prior to my AOS issue it was most likely to be the intake air leak so I loosened and retightened all the intake tube clamps and removed and reattached the upper AOS to intake tube. the value of RKAT is reduced slightly but the car seems to be running fine, so i'll drive it this week and see if anything further develops. in the mean time I ordered new fuel cap, spark plugs and fuel filter as these items are due at 70k miles and can only improve the current situation. more to follow as things progress this week. __________________ "It broke because it wants to be Upgraded " 2012 Porsche Performance Driving School - SanDiego region 2001 Boxster S, Top Speed muffler, (Fred's) Mini Morimotto Projectors, Tarret UDP, Short Shifter, Touch Screen Dual Din Radio, 03 4 Bow glass Top (DD & Auto-X since May 17,2012) Last edited by jb92563; 05-12-2014 at 07:33 AM.