shadowknight

The car is a 89 s4, I'm having some issues with the car bogging down from a standstill under hard acceleration. Other than that it runs fine. The car is stock with exception to a GTS Muffler and X-pipe. How do I determine if it's the MAF or another component(s) that may be the problem.

John Speake

How many miles on the MAF ?

shadowknight

John I have 120,000 miles on the car.

John Speake

If that's the original MAF then it is well past it's sell by date.

If you send it to my agent Louie Ott (as per my signature) he has a test jig to check out if it is the problem or not.

safulop

That might be the last original MAF on a 1989 model that is still sort of working.

FredR

With these cars [and most others] time takes its toll and performance degrades- sometimes dramatically. It helps us if you can pin point what maintenance has been done/what components have been replaced in the near past and even that is no guarantee.

Typical performance issues usually reduce to one or more of the following:
MAF
MAF plug and wiring immediately behind it
Fuel pressure regulator/dampers
Ignition leads
knock sensors
Hall trigger
Fuel pumps[less likely but..?]
Faulty or dirty fuel injectors
Inlet manifold issues
Cam timing [less likely but..?]

Basically when searching down performance issues all the above need to be eliminated from the line of enquiry. Needless to say the engine itself could have issues but generally a lot less likely as long as it has been looked after reasonably well.

Rgds

Fred