Trying to start a 931 after 8 years of sitting

[mattaebersold]

I recently acquired the car, and I’m working to get it running. I put a new battery in it the other day and changed all the fluids. It will turn over after awhile (I don’t want to keep hammering on the starter, but after about 10 tries it will start).

Symptoms:
- first is when I’m trying to start it, it takes a long time, and needs gas pedal action to FINALLY get it going

- This is making me wonder if the spark plugs aren’t good, or something with the fuel delivery?

- When it does start it will go up to 2500rpm and sit there for about 10-15 seconds

- After that it begins to sputter and eventually die

- After a few seconds of running, LOTS of white smoke comes out the back

- it’s not blue, but it’s also thick and lingers like oil burning (and smells)

- Oil pressure light is on

- I put in probably 3 gallons of fresh gas, but the fuel meter says E, and fuel light is on

Thoughts?
- possible head gasket which is causing all the oil to burn?
- I know the turbo uses oil, could it be that?
- Something is up with the fuel delivery… fuel pump? Relay? If so where would those things be?




Some other oddities
- I drained the coolant and tried to replace it, but it will only fill up the reservoir, and it doesn’t go into the radiator. Is there a separate radiator fill cap?




Video 1 (starting and high idle)

IMG_2856.mov

Video 2 (white smoke pouring out the back)

IMG_2855.mov

[mattaebersold]

UPDATE
I got it to run for about 1-2 minutes without white smoke. The smoke was much less, blue, and lingered just for a bit before clearing up. But it sputtered and died after that. I pulled the front plug, and it was totally black, and the threads were oil-y. After it died, it wouldn't get going again no matter how much I tried the starter, which makes me think the head gasket is failed and the plugs are getting caked with carbon & oil, so there's no spark. Another possibility is that the fuel pump(s) are not working (boost bypass?) and when it was running, it was just the gas in the lines, and my new fuel isn't coming in, which caused it to die. I have a feeling it's more related to the head gasket because of the state of the plugs.*

[944 Ecology]

Time for a compression check, or, better yet, a leakdown test.

[DannoXYZ]

you need to completely clean fuel-system

injectors sent out for cleaning and flow-testing

need to floss every fuel distribution line.
remove them from fuel distributor and soda blast them

due to restrictions on chlorinated cleaners, there's nothing you can spray into fuel passages to remove the dried gas varnish. It's plastic and needs mechanical scraping to remove

[djnolan]

Originally Posted by DannoXYZ

there's nothing you can spray into fuel passages to remove the dried gas varnish.

How long can fuel sit before this happens?

[Spring44]

Originally Posted by djnolan

How long can fuel sit before this happens?

My 944 sat up for 7-8 years and I had to drop the fuel tank and have it professionally cleaned/blasted/coated inside and out by a shop using the Tank Renu process. Look for one in your area!

That and replacing the fuel pump, filter and cleaning the injectors solved all of my fuel problems. The tank, pump and filter were all full of varnish, rust and tar and could not be cleaned by just flushing it in place with solvents.

The cleaning and coating cost just north of $400 and I had to drop the transmission to get it out, but it saved much more future frustration