My recently acquired '86 951 has decided to run like crap after changing oil, filling the gas tank with fresh fuel (the car may have sat for a while) and re-attaching the bottom screw of the distributor cap. Plugs were fouled and the engine would only run while I sprayed brake cleaner into the intake. Because of that, I've been suspect of the fuel pump being faulty. Since then I've replaced the fuel filter, entire ignition system, rebuilt the injectors (one was bad and had to be replaced), new NGK plugs, all new vacuum lines, intake boot, fixed some engine sensors that simply weren't connected, checked the cam timing, new aux water pump, and a couple of new engine sensors. Also decided, since the AOL seals were shot and there was oil in the intake, to rebuild the turbo while it was out and replace the power steering rack (it was leaking bad and had to come out to get to the turbo mounts anyhow). The cat was removed by the PO and the O2 sensor moved to the down-pipe. Now that my recovery from knee replacment surgery is almost complete, I'll get back to work putting it all back together. Wish me luck.

 

AOL seals? Your car has internets? LOL good luck!

 

Check vacuum at the FPR and dampener.
Measure actual pressure in the rail.
Check voltage-output of AFM from closed to full-open. Make sure no drop-outs or spikes.

 

I've replaced so much in my efforts to make sure that everything is new or reman so the car will be reliable, long term that I forgot to include installed braided engine bay fuel lines, silicone vacuum lines, new FPR and FPD and plan to put a gauge on the rail to see what the pressure and delivery is. The engine wouldn't go beyond 1800 RPM without trying to die, once I got it running. I'm hoping it's the fuel pump because it sounded loud when I jumpered the DME relay.

Just have to re-assemble all the parts and see how it goes from there. There's SO MANY!

If I didn't love working on these cars so much and solving problems like this, I'd buy an old VW bug and spend my money on beer.

 

Great attitude! Best of luck on getting all working nice.