rufrob

Rescue 928
87-manual.
Barely running , very rich, fouled plugs, sun damaged interior, f'ed up dash, fuel level sensor MIA, washer fluid inop, sun damaged paint, no headlights.
Fixed the windows and lights,
The rough running has stumped me.
I've cleaned the plugs and swapped igniter and MAF.
I have spark.
It runs smoothly for about 10sec at first start then rough with smoke and the smell of fuel.
The plugs come out wet.
Any suggestions?

Darklands

A broken hybrid chip in the engine controls? Do you know someone with a running S4?
So you can swap the computers!

Jfrahm

Also typical of a bad FPR or damper pushing fuel into the vacuum system.

rufrob

Swapped 2 FPR. Same issue none are leaking.

rufrob

I'll pull the computers and clean them. I found the CE wet and fuses and relays corroded. Someone removed the rain guard at the base of the windshield.
Seems weird that all injector would be leaking.

rufrob

928s are few and far between where I live.

Petza914

Swapped with each other or a good spare?

I don't know the 32v cars well, but believe one is a regulator and the other a dampener - and are not interchangeable.

slownrusty

I'm betting money it's the LH.
Typical failure point for the '87 and '88 S4 cars.

My '88 did the same thing recently. Fired it up no problem, reversed it out of the garage into the driveway and then refused to start. I was lucky to borrow a friend's LH.

Best of luck and let us know what you find.

Curious...do you know how many 928s were imported to Japan?

rufrob

How many Porsches imported to Japan is a hard question to answer since back in the 80-90 there was no Porsche Japan instead there were a couple of authorized importers. Then there were the many used car personal imports mostly from Germany and the US.

rufrob

Got some done today. Cleaning the ground above the CE brought the blower motor and wiper washers to life. Pulled and cleaned the washer fluid tank yes there was mud in it.
Lots of miissing and broken fasteners.
Broke the t junction on the EVAP canister line.
Looks like someone opened and cleaned the ECU. I did the same again and it started and idled perfectly for 2mins then stalled. Restart was the same rough idle and fuel smell from the exhaust.

rufrob

Takes a lot of time this thing

Michael Benno

No discounting the possibility of LH failure.

however the fact it starts and runs fine cold and then runs rich and stall when warm would lead me to think there is something not working correctly with the temp 2 circuit. Do you know how to test this per the WSM? Report back with results

Jersey_Sam

good job on restoring your 87 manual. Im doing the same with my 87 manual.
Sounds like an LH issue with you. Also be careful, fuel in the exhaust could cause a fire. Sounds like you have a leak in the injectors as well.
Lots of things to go through. Start with the ground points, from front to back, including the battery box.


i just finished the CE Panel, cleaned the contact points, put fresh fuses, fresh relays (Fuel pump, EZK and LH ).
Then do an intake refresh, Temp II sensor....fuel lines...

Do you know someone in Tokyo that rebuilds LH and MAF? they usually go bad after years of sitting, some parts corrode in there...

If not, send it to Rich Andrade, will be back in a day or two, or to 928rus

https://electronikrepair.com/home-page

also check out this thread.

https://www.928oc.org/forum/928-oc-t...18-won-t-start

Good luck and you can PM me if you need any advice.

Sam

rufrob

Thanks Sam.
I'll check them out.
Tomorrow clean all grounds, finish the right side wheels, brakes and compound the bodywork.
If i have enough daylight pull the dash and seats for reupholstering.
I will check the vacuum lines and swap another FPR

hwyengr

There is a factory diagnosis test plan manual for the fuel and ignition systems in the tech docs sticky thread. It would probably be better to methodically work through the systems instead of scattershot swapping and pulling things apart.

That way you can figure out what’s good and what’s not. Because there are a LOT of variables at play, here.