82 911 won't run

ssrodder · 02-09-2009, 03:18 PM

I have an 82 3.0 with 59,000 miles on it. Has not been run in about five or six years. Did all the pre start up work such as removed and cleaned gas tank and screen on tank, flushed fuel lines in both directions, changed fuel pump, removed spark plugs, squirted oil in all the cylinders and cranked it over with the coil disconnected for about a week. Fuel pump pumped a good supply of gas into a container before I reconnected all the fuel lines.
Replaced the plugs with Bosch W5DC. It had NGK BPR7ES plugs in it before I changed them.
It will start immediately, but will die just as fast. It seems that the fuel pump stops pumping gas as soon as the car starts. If I shut the ingition off as soon as the RPM start to drop, about 10 seconds after it starts, it will start right up again and then stall again. If I try to feather the throttle to keep it running, it will backfire and then stall.
I noticed that I am getting no power to the micro switch that is mounted on the throttle linkage that is located in the engine compartment. I have power at all three fuse that are located in the engine compartment. However, I have no way to check if I losing power to the fuel pump once it starts.
Any and all suggestions appreciated.

mack6820 · 02-09-2009, 04:43 PM

timing?

euro911sc · euro911sc's Garage

Bad fuel pump relay? You can jumper the relay out to test or buy one for not a lot of $. You can also replace it with a spare black one for testing as well.

I doubt that the timing is off given the millage, but you can check it.

What about the fuel distributor shaft getting stuck? Tough to diagnose or fix...

Bad distributor part? I believe you can get internal replacements from Napa. A search here will provide the part number. Maybe in one of Gunter's threads.

Bad coil? there is a resistance check you can do to test the coil.

Sparkplug wires put back in wrong order? Either on the cap or on the heads.

Valve stuck open? Would probably still run on 5 cyls though...

Those are my best guesses.

Best regards,

Michael

ruf-porsche · ruf-porsche's Garage

Maybe not a fuel problem but a vacuum leak, such as a BLOWN AIRBOX. You did mention that the engine backfires.

Flat6pac · 02-09-2009, 05:46 PM

Lifting the airflow sensor will possibly keep the pump running.
Possibly not enough fuel pressure to service the center of the fuel distributor
Before you fool with too much you need to disconnect the oxygen sensor because Llambda will try to over come your alterations

Bruce

my1st911 · my1st911's Garage

Maybe I am not completely understanding the chain of events correctly, but first thing I thought was ignition switch. It starts and runs, but quits when you release the key from what I gathered, and you dont have power to the fuses. Just a thought

T77911S · 02-10-2009, 03:19 AM

check for power at the CD unit with the key on.

with the key off, lift the AFM sensor plate. it should move very easy. with the key on, lift the AFM sensor plate, the fuel pump should run and you should feel resistance on the plate as you lift it.
when these cars sit, the plunger in the fuel distributor can get stuck.

did you check/clean the little screen going into the WUR?

fastfredracing · 02-10-2009, 03:27 AM

My guess would be that the FD is stuck/frozen/rusted. The car is probably starting off of the cold start injector,

psalt · 02-10-2009, 03:40 AM

However, I have no way to check if I losing power to the fuel pump once it starts.
Any and all suggestions appreciated.

Take a look at the wiring diagram. One circuit powers the fuel pump during cranking, a different circuit powers the pump with the key in the ON position. There is a safety switch on the air flow sensor to stop the fuel pump in case of an accident, the easy way to check is to manually lift the air flow sensor with the key ON and listen for the pump. If that is OK, suspect a lean condition at cold start and don't pump the pedal, you only make it worse and you can cause a back fire Try disconnecting and plugging the vacuum advance, that will give you a bit more cold idle and it may catch and keep running. You really need to check the system and control pressure to know what is going on. Once it's running you can check out the CIS lambda with a dwell meter. Check the archives.

Phillip_G · Phillip_G's Garage

I agree with FastFred, sounds like a fuel delivery problem. Either bad FD or air leak causing metering plate not to lift and thus no fuel. Manually lift the air meter plate and listen for fuel flow from injectors.

Phil

don gilbert · don gilbert's Garage

you said that you cleaned the line to and fro, did you also chek the return line, simular problem i had on a car that had been sitting and your exact condition, (crank and die) turned out to be a restriction in the return tube that goes in the tank. un hook you return line from engine and see if you can blow air and hear bubbles in the tank. just an idea.

T77911S · 03-05-2009, 10:51 AM

did you get it fixed

kodioneill · kodioneill's Garage

pull the injectors leave lines connected. bleed the injectors by lifting the fd sensor plate. get two cans and place the three injectors on each side in them. lift the plate. you'll here a squeal, keep the plate up about an inch until the fuel flows equally.
reinstall and start the engine.

nh911 · nh911's Garage

My car did the exact same thing and i tried everything and the found out that the fuel line from the distributer to the wur was a little clogged after i unclogged that the car started right up and ran perfectly.