HELP: Engine sputtering @ mid-throttle

[PowerHaus944Turbo]

I have a 1987 944 Turbo which has been fitted with an Autothority mass-airflow sensor, K-27 Turbo, and upgraded DME software. The car idles properly, but at mid throttle / high rpms it begins to sputter, horribly. At full throttle, the car accelerates fairly smoothly, albeit at a very fast pace. The only progress that I have made has been to adjust the mixture to be richer with the idle screw on the throttle body and the in-line set screw on the Autothority harness (though this only has produced marginal results which vary with temperature). Could it be the throttle switch? Does anyone know the proper pins to check? (The Hayne's manual indicates pin 12, and there are only 6.) Could it be my mass-airflow sensor? (I hope not.) Any help would be greatly appreciated.

[Lawrence Coppari]

I have the same system with about 33K on it now (MAF, K27DR, fuel pressure). Only trouble I have had is with the connection right at the mass flow. It is exposed to weather and has caused problems before. I unsnapped it, cleaned the prongs, etc. and reattached. My problem was more at idle, however. A little extra resistance there causes problems. Good luck. PS-I also have the extrude honed intake and ported head. Thing runs well.

[PowerHaus944Turbo]

I also have the honed intake, bored throttle body, etc... I just can't seem to lick this problem. The Autothority sensor is 10 years old, though.

[Lawrence Coppari]

What about something simple like a coil or distributor cap, rotor or something of that nature?

[cyclemike]

I had a similar problem with my 87'951. When I started the car in the morning and took off it would stutter at about 3-6K rpm. I was also smelling oil and watching smoke from the tail-pipe. I rebuilt the turbo and the stuttering ceased. I think over-night oil was building up in the turbo. Try rebuilding your turbo.(Easier said than done,right? trust me I know!)

[This message has been edited by cyclemike (edited 07-27-2000).]