View Single Post
David David is offline
Registered User
David's Avatar
Join Date: Apr 2002
Location: Houston (Clearlake), TX
Posts: 8,688
I've been fighting a problem where the left side spark plugs showed lean and the right side rich.

I suspected my fuel system was the problem since it ran in series. I re-ran the fuel lines to parallel where the fuel line split off to each fuel rail, added a Marren fuel damper at the end of each fuel rail, and ran the return lines to each side of the 3 port fuel regulator. Well all that time and expense did nothing for the problem.

I checked the electrical system to the injectors and didn't find any problems.

Then it was suggested I check the cam timing (actually my tuner suggested it right off but I was being stubborn). So after having two experienced folks tell me to check timing, I checked it and sure enough, I had the right cam too retarded. I reset the cam and now both side's plugs look lean. The lambda sensor shows the engine running rich, so I'm not going to worry about it til it's back on the dyno.
2014 Cayman S
2011 Cayenne Turbo
1979 930 (475 rwhp at 0.95 bar)
Old 04-29-2007, 02:35 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #34 (permalink)