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Trying to start a 931 after 8 years of sitting

 
Old 12-11-2018, 02:03 PM
  #1  
mattaebersold
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Default Trying to start a 931 after 8 years of sitting

I tried posting this on the main 924/944/968 forum, but this is an obviously better place, so I want to talk about it here too...

I recently acquired the car, and Iím 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 donít want to keep hammering on the starter, but after about 10 tries it will start).

Symptoms:
- first is when Iím 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 arenít 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

- itís not blue, but itís 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 deliveryÖ 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 doesnít 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


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.
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Old 12-28-2018, 01:30 PM
  #2  
Swenny
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I'm not that familiar with the 2 liter but after sitting for 9 years you'll need to clean the tank,change gas filter(s) check pumps for crud and possibly change the fuel lines and the FPR. Oil may be sludge, leave the plug off and drain as long as possible,then flush with clean oil.
Then there's the cooling system,new water pump,thermostat and hoses and flush the whole thing with cooling system flush.
Fuel injectors are most likely clogged up. Change your timing belt (not as critical as the 2.5 but important)
If you do pull the lifters out clean and soak in motor oil for as long as possible( assuming that you have lifters ~ )
There's the basic, you'll most likely find other stuff that's has deteriorated or is broken. Vacuum lines,power brake booster valve and anything like the 2.5 has ( IAC if applicable ) needs to be checked and replaced if necessary.
Just getting your beast to fire up and sound like my 90 year old grandmother after a fifth of scotch and two packs of cigarettes is a feat in itself. Go to 924.org for info on the turbo.
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Old 01-03-2019, 06:45 PM
  #3  
mattaebersold
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Default Update!

Ok, and update!

It's running pretty smoothly when I can start it up, which is about once per day I believe that's due to the head gasket. There is some oil residue on the plugs, and I think the plugs get fouled and it needs to sit in order to clear it up. That said...

It idles high around 2,000 for a couple minutes, then it goes down to 1,000 and sits there for awhile. After that it starts to roller coaster a bit, like it dips, catches itself, and dips again, with increasing severity until the dips are so low that it dies.

A few things of note:
  • white smoke still visible, I believe this to be coolant getting in the combustion chamber (head gasket)
  • won't re-start for awhile (I'm assuming head gasket letting oil into the chamber/plugs)
  • really squeaky (see vid, possibly timing belt? Bearings around that?)
  • won't throttle past 2,000 starts to immediately sputter and die (vacuum leak?)
  • wavy idle to the point that it dies (vid, unknown)

VID
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