Please make my car shut off

930 Guy · 07-10-2005, 08:17 AM

It must be something simple right. 930 won't stop running. I know it must want me to drive it as much as I can but come on!
It has a new ignition/fuel cutoff relay.

John Walker, are you out there, and did you get the gift I sent for fixing my last problem. I sent it last week. bw

efhughes3 · efhughes3's Garage

??!! If it won't stop, we can all take turns driving it, bring it over.....I'll go first

asphaltgambler · 07-10-2005, 08:38 AM

Possibly the electrical portion of the ignition switch bad OR the mechanical part of the switch is not returning to the 'off' position even though it may feel like it.

930 Guy · 07-10-2005, 08:40 AM

Ed, you can drive. Nice little run on Josey Lane from 544 north to 121. Try it at full speed some time.

Ign. switch is fairly new.

efhughes3 · efhughes3's Garage

That is a fun little area. I've got some neat country roads (Argyle area) near my house that are fun too. Hope you get it solved, but if not.....

PorscheGuy79 · PorscheGuy79's Garage

Quote:

Originally posted by efhughes3
??!! If it won't stop, we can all take turns driving it, bring it over.....I'll go first

I just read the emergency. We cant just let her idle. Im on the way.

Seriously though if you were need to shut it off have you tried to stall it out?

930 Guy · 07-10-2005, 08:59 AM

Well, I'm not exactly drinking a beer, typing on my PC while it purrs in the drive. I dumped the clutch. Do you think I can explain that move to the Valet?

ZCAT3 · 07-10-2005, 09:08 AM

930s have a built in run-on circuit that keeps fuel pumping for a few seconds after you shut off the ignition. I am not entirely sure why Porsche did this, but perhaps it was to act as a turbo timer to help cool the turbo a bit and prevent oil coking after a hard run. In any case, a bad run-on switch could cause it to continue to run after the ignition is off. In the meantime, you could just pull the fuel pump relays to get it to shut off.

930 Guy · 07-10-2005, 09:14 AM

Bill, I changed the relay you speak of a few weeks ago. It is to run the eng for a few seconds to burn fuel in the intake after shut off. I think the true name is ignition cut off relay.

ZCAT3 · 07-10-2005, 09:23 AM

I wonder if there is something wrong with the new relay?? Why did you have to replace it? I know in our 930 the engine would run on for what seemed like a little too long - maybe 10 -15 seconds - until we replaced the WUR.

930 Guy · 07-10-2005, 09:37 AM

I replaced the relay because I was having trouble that proved to be my rebuilt cd box. I wanted to make sure it wasn't keeping my car from starting. I have the old one, I will swap.

930 Guy · 07-10-2005, 10:01 AM

Switched out for the old relay. Still won't quit.

73911guy · 07-10-2005, 01:19 PM

One of the diodes in the alternator may have gone bad and is letting current pass through the electrical system. Gave me fits until I R&R'd the alternator in my '73.

Jim

930 Guy · 07-10-2005, 01:37 PM

Alt was replaced with new unit from Porsche about 2 1/2 years ago. How do I test in the car? Out of the car?

Nitrometano · Nitrometano's Garage

Quote:

Originally posted by 930 Guy
I replaced the relay because I was having trouble that proved to be my rebuilt cd box. I wanted to make sure it wasn't keeping my car from starting. I have the old one, I will swap.

Some times the MSD like CDI fails and one of the problems is with the ignition off, they still giving spark into the engine. And this cause the engine to run off. This is the problem that we have the last week with a drag racing car.

930 Guy · 07-11-2005, 04:50 AM

I am using a replacement box. I put it in on Friday, drove all day, all was ok. Sat couldnt get it to shut off. So, it might be the box not the car or some other item?

chrisp · 07-11-2005, 05:14 AM

I have been chasing this as well. I haven't gone through all of the steps that you have. I just stall mine out which probably isn't great but I only run the engine 10-15 times a month.

The weird thing with mine is I get four separate conditions

1.) Turn the key off and nothing happens but tach starts to cycle high to low. Then I stall it.

2.) Turn the key off and the engine revs up and down for a couple of seconds and shuts off.

3.) Turn the key and engine revs up and down for an endless period until I stall it.

4.) Turn the key and it shuts right down as normal.

For me #1 is the most frequent and #4 is probably one in twenty.

930 Guy · 07-11-2005, 09:36 AM

My car shut off today. Only change was a blown fuse to the blinkers. Does this make any sense?

chrisp · 07-11-2005, 01:11 PM

I'll double check all of my fuses. I think I've done that already (been chasing this since last year) but can't recall.

john walker's workshop · 07-11-2005, 01:46 PM

see if there is a single filament bulb in a double filament socket, left rear.