UK-POLOS.NET - THE VW Polo Forum

Hi folks, 9n3 (2007 1400cc Petrol Polo)
(Sunday 31st June)
I was cruising on the Motorway (70mph), when suddenly there was a cloud of smoke or steam (unsure which) out of the rear of the car, similar in density to coolant burning on the exhaust (as soon as I see this I turned off the engine and rolled to a stop...)

Upon checking the levels of the engine the coolant was high (Id filled to maximum that morning) plenty oil in (car had been running but was half way between minimum and max)

So I called the AA to get towed to a garage, when there we start the car and immediately get a cloud of oil rich smoke (same density as a blown engine) from the exhaust.

I went to the garage today and we cannot work out what is wrong with this engine.

Runs and drives sweet as a nut (car was parked but run at fast idle speed, then driven 5 miles, totally fine!) no misfiring or hesitation at all.

NO abnormal coolant system pressures, no high temperatures and cooling fan operates normally, heater blows roasting hot air, not abnormal for the car.

No oil and coolant mixing visible (on dipstick or expansion vessel)

The only possible issue we can see is that the oil filler cap sucks itself onto the motor if I remove it and hover it over the cutouts.

Oil is circulating and there is no EML or stop warning lights.....

Would a blocked or faulty PCV valve cause this issue?

We are clutching straws currently.

Any further information required I will do my best!

Help please!!

Cal

I'd start with a new PCV valve.

Brilliant, I shall try that! Car has driven 20 miles faultlessly, with no problems other than the oil lower than it was on the stick...

Just cost me £300 in MOT repairs lol

Thanks for the reply, I shall try the PCV valve, I'll also remove and flush the pipes connected to this (within reason)

I will report back with my findings

Regards

Cal

Further update for you all.

The car has run perfectly since this incident, my local VW dealer has my Oil Seperator on thier shelf (had to order from Germany but am awaiting them getting a job time to fit it.)

I can't find a PCV valve part number at all.

Volkswagen's excuse for the delay is that they have never fitted one so need to generate the job time....

Thanks again folks

Cal

I'd start by performing a diagnostic scan. At least it would possibly save guessing.

My wife had a 2002 Polo with the BBY version of that engine, and it after maybe 8 or 9 years and 80+K miles kept having issues with pinging/pinking and an desire to drink engine oil, eventually I put 2 and 2 together and got my local VW parts dept to order in a new oil separator and that fixed its pinging/pinking and its desire to drink oil, we never ever had trouble with smoke showing out of the exhaust - okay the tailpipe end was a bit black and oily/gummy, but that was as far as it got.

I'm not sure where the controlled restriction is for the air being allowed to purge the crankcase on that version of that engine, my daughter's late 2009 SEAT Ibiza with the BXW version of that engine had an evolved/improved version of that oil separator with added water cooling loop, though it did not give any trouble over its 10 years 65K miles with her.

I think that on that BXW version, the crankcase "separated air" gets piped into the airbox - so hopefully your VW workshop had a look into the air box before ordering in a new oil separator, these things are just a cyclonic design device that hopes to strip out the oil and return it to the sump while passing the remaining vapours into the engine via the air box. There was a change in the O-rings design maybe in 2010 or so, that was only, I think to stop leaks where the oil separator fits onto the engine.

Edit:- it could be that the restrictor for circulating air is inside the oil separator and so VW dealer is doing the correct thing.

Another Edit:- what about 036103175C - has your engine still got the "covers the top of the engine" ait cleaner - ie BKY or BBZ, if so remove the air cleaner, you will need to remove a small hose before you can take the air cleaner away out of the way, that small hose terminates on the PCV valve that is bolted onto the engine. Or what about 030103175B if your engine has the air box behind the engine ie BUD. Also in both cases make sure that the small pipe is not blocked or has a leak.