chewy8000

Hello everybody! I recently recieved an 81' US 928 5-speed with 60,000 miles as a wedding present from my father (another Porsche fanatic). The car sat under a cover for about 10 years. It idles ruff and hesitates badly under 2000. I put a new cap, rotor, plugs, air filter, fuel filter on it and seems to have gotten worse. I have run a few bottles of fuel injector cleaner and nothing has changed. I have searched the archives and found a few things about the issues I'm having, but nothing at the rpm's it's occurring at. The car is in perfect condition and the engine is spotless. many of you might have seen it at Frenzy 7 in VA. Now that I am a new rennlist member I look forward to hearing anyones solution to these symptoms. Thanks

Randy V

Was your father unhappy that you were getting married?

If he wants grandkids, he better get that thing running right for you, otherwise you might end up sleeping on the couch after spending countless evenings wrenching on it...

chewy8000

Thanks for the advice. Fortunately my wife likes to wrench on it as much as I do!

Shane

Wow, lucky man!

Randy V

OK, now for a serious answer.

Search the archives for 'green wire'. Sounds like it may be your problem.

Nathan Valles

Simple test for Vaccum leaks:

Put the car out in the driveway then spray carb cleaner all around and under the intake manifold. Be very careful not to spray the distributor or any electrical leads. If the idle smoothes out or speeds up then you have vaccum leaks in that area.

chewy8000

Thanks guys. I did notice almost all of the rubber lines on the motor have cracked and frayed on the ends. One of the really bad ones was a 3-4 inch line just under the right side of the air box. I noticed it changing the rear right plug. I did clean the flap on the MAF while I was in there. I don't know what the 3-4 inch piece I speak of does. I can't find it in the manual.

Cobey

Sounds like you're ready for a vacuum line change. This ought to help a little:

http://nichols.nu/tip305.htm

Curt

For sure check the green wire to see if its cracked and brittle and grounding onto itself.

You will also need to replace every vacuum line on the car. Then it will idle and run good.

chewy8000

Where can I find this green wire?

chewy8000

I just found a white wire going to a switch that looks like it has something to do with the throttle. It looks like the throttle engages the switch at half throttle. This white wire has been almost eaten all the way through by some sort of creature.

GlenL

Sounds like you got 928 electrical gremlins! Get the large rat traps and bait them with $50s and $100s.

The green wire runs from the distributor to the ECU on the right fender. Check it for fraying and clean the contacts. It carries the magnetic pick-up signal which is very weak.

My car ran like crap when I got it. Had been sitting for a while. Tankfuls of driving, maybe 1000 miles, later it was running much better without any engine work.

chewy8000

I just went out and closely inspected all electrical and vaccum lines. About 1/4 of the elctrical have been chewed through including the green wire. Is there an easy way to pop the clip connecting the green wire to the distributor? Are these items that need to be replaced with factory wiring from the dealer. Where can I find if not? Thanks for all your help guys, looks like it will be a while before I'm running smooth. All this might not even be the problem! At least it's a start.

GlenL

The green wire will come off the distributor if you unscrew the clip.

Dealer!? Forget the $50s and just use $100s. Search the archives and read that "FAQ" post. Also click these:

www.928intl.com
www.devek.net
www.928gt.com

Incidentally, I've called the local dealers several times for parts and they have NEVER had what I wanted on hand.

chewy8000

Thanks GlenL. I had enough length left in the wiring and luckily the mice nibble on the ends. I already cut the bad wiring of and put new clips on. I tested the vaccum lines and they were fine. I clipped off the ends and stuck em back on anyway. Much more snug. i attempted to remover the clip, but how the hell to you get to the screws! You need spagetti arms to work on this car.