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Discussion Starter #1
Hi all,
It's been a long winter here in Sweden, the van (2.5L Petrol AVT Syncro) has done a load of trips but I have never managed to stop the annoying occasional rough idle and poor running. Its equivalent MOT is up soon and one thing that is getting worse is the exhaust smell. It smells rough I can't see it passing emissions, often of Petrol. I bought a cheapish replacement exhaust several months ago and no doubt the cat in that is screwed now. Anyway, I had a MIL and felt what I think is s misfire / rough running, I broke down and replaced the coil, which seemed to work ok, got me home, but to solve the underlying issue I started looking at the injectors and plugs from the following guide

HOW TO - Test G70 AIR MASS METER (aka MAF Sensor).

The MIL and it came back, Id say that it feels a little rough driving, but warms up fine and copes pretty well given its cold here.

Readout:-

16804 -Catalyst System Bank : efficiency below threshold
16689 Cylinder Misfire detected

Ohms tested the injectors and all in order, plugs looked ok to me, I took off the mass air flow sensor to clean but in doing so I pull the oil breather pipe off and liquid came out of it. Inside it was caked with white sludge. The oil filler cap looks like the attached.

So, my assumption is it may be the head gasket, but what's the best way to check? I'm not losing Coolant, but have used a lot of oil, I think there is white smoke out the exhaust (Its smells bad) but difficult to know in -20oC. Could it be oil seals, or is it very likely the head gasket? No overheating, the temp has always risen exactly the same to middle gauge and not deviated (summer/winter).

Id quite like to fix it myself but struggle with no manual for the petrol engines. So I guess my question is, what's the best way to rule out a head Gasket failure, should I buy a compression tester for the likely failure in cylinder 5? there are also the liquid gas testers kits available, but as I'm not losing coolant could the break be worse than the gasket and potentially not include coolant? Is there another way to test that will be conclusive?

Thanks in advance, Laurence

Oil breather

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that doesn't look good for the head gasket I'm afraid. Unless there is an oil cooler that uses the coolant water I wold say that amount of snot in the filler cap is indicative of head gasket failure.

Do a compression test if you can
 

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that doesn't look good for the head gasket I'm afraid. Unless there is an oil cooler that uses the coolant water I wold say that amount of snot in the filler cap is indicative of head gasket failure.

Do a compression test if you can
Thanks for the reply - ill go get a compression tester
 

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I once had an engine with blown headgasket but with excellent compression.
Turned out the headgasket was only leaking between an oil way and the water jacket.
 

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That's definitely coolant getting into the oil! Sometimes with a busted gasket or cracked head you can see substantial air bubbles coming up into the header tank. Hope you get it sorted, good luck.
 
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