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[mattaebersold]

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 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


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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1980 931
1991 Japanese Classic Mini
2000 740i
2006 530xi Wagon

[morghen]

Did you do a belt replacement? if you didnt yet, dont turn the motor anymore until you do.
Best would be to take the car to a CIS injection expert in your area.
The injection system is the same one as golf GTi and jetttas of the same era.

The first problem is proabbly in the fuel system but it may be that it has broken rings or worn rings as well if it starts hard and the fueling is ok...but right now the fueling is surely not ok.
Injectors are probably not spraying properly, fuel pump may be not pushing sufficiently, warm up regulator is surely not working properly.

Then the turbo may be shot and oil gets into the exhaust.
Then if the plugs are oily you may have some valve steam seals to change...to do that you need to do a headgasket change as well.

Looks like an overhaul project to me.
Fuel system needs a refresh, turbo needs a refresh, maybe head needs a refresh and maybe rest of the engine needs refresh.
After that, you may find that you need a new clutch and a gearbox refresh.

Dont want to scare you but this may end up costly...the 931 is NOT a cheap car to restore even to running reliably standard.
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[Paul]

You stated: oil pressure light is on

I assume you mean while the motor was running....
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[morghen]

Didnt even see that, lol.
You really want to make sure that there is oil pressure.
What does the oil pressure gauge read?
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