Addressing codes one at a time is an expensive school!

Do you know which one came first? Did you know that there are decision trees for multiple codes?

In almost a quarter of million miles, my dealer has NEVER replaced more than one component!

Once, trying to fix a problem with the anti-lock brakes in my '90 744 TI, they kept it for two weeks

If checking for vacume leaks does not solve the problem, I would try this -

Clean all grounds, including the mounting location of electrical components (in case the mount is the ground) and engine straps.

Unplug and clean all connectors (look at the pins and sockets for pins that have moved - especially your mass air sensor ) add dielectric grease and zip tie any that you can.

----- OR -----

Pay your dealer one hour's labor to find the problem


BTW - Check the Mass air sensor plug first anyway.

Good luck
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'96 855R,'64 PV544 driver, '67 P1800 basket case, '95 855, '95 854, the first three are mine, heh, heh, 485,000 miles put on 9 bricks