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Discussion Starter · #1 ·
My 2006 saab 9-5 2.0t is using way too much fuel. Theres smoke coming out of the exhaust and on startup black liquid flying out of it as well. Im sure the oil and coolant hasnt been mixed. I also noticed that when idling the fuel consumption was slowly going up on the sid, it was at 21l/100km. Engine light is also on but i dont have a reader to check it at the moment but i might buy one. I disconnected the maf but that changed nothing. Anyone know what could be the issue or what i should check? Theres a slight hissing sound coming from near the fuel rail too but i couldn't find the exact point.
 

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Theres smoke coming out of the exhaust and on startup black liquid flying out of it as well.
exhaust is more than likely full of water from the combustion process,this happens when the car only does short trips and the exhaust doesn't get hot enough to evaporate the water..
 

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Discussion Starter · #13 ·
It still sounds like it's running rich. If the Check Engine light is on, the codes need to be read. They will quite likely point to what the problem is.
Okay so a few days ago the engine light turned off for some reason so now i dont think it was related to the problem i have. Bought a code reader too and there were no codes. Also noticed that on startup the big cloud that comes out of the exhaust has a blue tint to it. It smokes badly for about 30 seconds, then stops smoking for 1-2 minutes and then it starts smoking a little bit again but the color of that smoke is gray/transparent white
 

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Blue-ish smoke is from oil burning. If it only happens after sitting overnight then it's most likely from worn valve seals/guides. The other white/gray smoke could be from condensation in the exhaust, especially noticeable on damp days, but it should normally dissipate after a few minutes once the exhaust system heats up. However, if the inside of the exhaust pipe is black and greasy (as opposed to sooty) it could be from worn piston rings indicating a tired engine which would consume more fuel. Does the dipstick smell of fuel?

Without any trouble codes this will be hard to diagnose remotely.
 

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Discussion Starter · #15 ·
Blue-ish smoke is from oil burning. If it only happens after sitting overnight then it's most likely from worn valve seals/guides. The other white/gray smoke could be from condensation in the exhaust, especially noticeable on damp days, but it should normally dissipate after a few minutes once the exhaust system heats up. However, if the inside of the exhaust pipe is black and greasy (as opposed to sooty) it could be from worn piston rings indicating a tired engine which would consume more fuel. Does the dipstick smell of fuel?

Without any trouble codes this will be hard to diagnose remotely.
The dipstick does smell like fuel a little bit but the inside of the exhaust is just sooty, didn't feel greasy at all
 

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Discussion Starter · #18 ·
Also for the past two days it hasnt made a big blue tinted cloud on startup anymore so thats kind of weird. Now its just the normal small gray smoke. I have a feeling it could be because of the turbo too but i dont have a car toolkit to take things apart and check it. Probably will buy one though.
 

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The code went away before i got my obd2 reader, it didn't show any anymore. Might have been just a misfire code or something like that since the light turned on on a long drive.
TECH2 will read codes unless you erased them (disconnect battery).
 
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