Burning oil smell - VR6 w/ 128k miles

[G-Lad 0]

I was out and about at the weekend and pulled in to Decathlon, like you do. I noticed a nasty oil burning smell, and spotted an oily mess in the top of the manifold under the PCV valve.

 

I replaced the PCV last year with a Ford item and all is still good, however there was a good 10mls+ of engine oil throughout the rocker cover breather tube right up to the throttle body, with oil by that nearest spark plug and oil dripping off the bottom of the smaller bendy pipe attached to the PCV / air intake (the one with the inline sensor).

 

I've given the pipes a good wipe out and wire brushed the manifold clean again, and it all runs fine as before, with the smell now gone (albeit I think under performing a bit, but could be my imagination - it's a stock 16 year old car, albeit with a Mk4 plastic rocker cover and the usual slew of work for a car of it's age).

 

I'll monitor it over the next few hundred miles and see if it happens again, but what causes oil to get shot out of the back rocker cover breather pipe?. I'm sure that's where it came from, unless there is something crazy going on and it came out of the throttle body!? The MAF looked fine and clean, and was replaced last winter anyway, so it was all still as new looking.

 

It's done about 5000 miles on the current synta silver and filter, and burns about 500mls per 1000 miles or thereabouts.

 

I guess it's conceivable I over filled it, but I think it's unlikely as I am so used to chucking in half a litre every month or two I know it's half way from the top of the dip stick marker to the bottom for half a litre...

 

History: It used to run very hot until I had the belt and electric coolant pumps replaced, along with the thermostat, sensors, heat exchanger and an acid coolant system flush.

 

NB: I recently changed the clocks as the coolant never went over 90 (unbelievable) the oil was often between 110 and 120 (again, unlikely), the speedo over read and the revs under read! All read outs are much more believeable now and it doesn't go over 110 on the oil unless I'm *really* pushing it for a significant time period (on private roads of course).

 

I assume the advice would be to take out each plug and look for oil fouling, which would suggest valve stem seals or piston rings getting worn, explaining the moderately high oil usage. This doesn't answer why I have a fair amount of oil coming into the air intake pipe though, does it?

 

Thanks folks

 

 

Chris

 

PS: is it worth me declaring my clock swap to the DVLA or Insurance Co, since my milage now over reads by 44800 miles? I wouldn't like to be in an accident and half issues with my Insurance Co claiming i've mislead them about the usage or something.

[G-Lad 0]

anyone got any idea? I didnt drive the car in the week and have done about 75miles of mixed town and A road driving this weekend. The exhaust manifold guard has got drips of oil on it again. The dip stick says it isnt over filled, and im pretty sure the oil is coming through the rocker cover breather and through the new ish pcv value into the air intake. It seems to be leaking out through the flexi pipe with the sensor and dripping onto the hot manifold guard.

[Kevin Bacon 5]

I assume the advice would be to take out each plug and look for oil fouling, which would suggest valve stem seals or piston rings getting worn, explaining the moderately high oil usage. This doesn't answer why I have a fair amount of oil coming into the air intake pipe though, does it?

 

Unfortunately it does. Worn bores allow too much of exhaust gases past the rings and into the crank case, which blasts excessive amounts of oil vapour through the breather, which then condenses into oil in your intake pipes. All very common and normal.

 

1/2 litre per 1000 isn't horrendous by VR6 standards, but it should be doing 1 litre per 4000ish on a standard engine in good condition.

[dukest 0]

PS: is it worth me declaring my clock swap to the DVLA or Insurance Co, since my milage now over reads by 44800 miles? I wouldn't like to be in an accident and half issues with my Insurance Co claiming i've mislead them about the usage or something.

 

yes, thats exactly why you need to do it..

[G-Lad 0]

I assume the advice would be to take out each plug and look for oil fouling, which would suggest valve stem seals or piston rings getting worn, explaining the moderately high oil usage. This doesn't answer why I have a fair amount of oil coming into the air intake pipe though, does it?

 

Unfortunately it does. Worn bores allow too much of exhaust gases past the rings and into the crank case, which blasts excessive amounts of oil vapour through the breather, which then condenses into oil in your intake pipes. All very common and normal.

 

1/2 litre per 1000 isn't horrendous by VR6 standards, but it should be doing 1 litre per 4000ish on a standard engine in good condition.

 

Oh dear, thanks Kev!

 

Well, lets see how long the old girl has left in her! I'll have to start swotting up on the engine rebuild costs and compare / contrast with the price to do a transplant / upgrade...

 

I'll get the plugs out and have a look ASAP.

[G-Lad 0]

PS: is it worth me declaring my clock swap to the DVLA or Insurance Co, since my milage now over reads by 44800 miles? I wouldn't like to be in an accident and half issues with my Insurance Co claiming i've mislead them about the usage or something.

 

yes, thats exactly why you need to do it..

 

Thanks, will do!

[Ice White Socks 0]

I had exactly this issue- I just pulled the PCV off and cleaned the joins, retightened the clips, and that was that. I wouldn't automatically assume its a symptom of a worn engine as mine uses no oil, keeps its plugs perfectly, doesn't smoke etc. It only takes a few drops of oil to make a nasty smell if its just being left to char itself on the manifold.

[fla 9]

might be worn piston rings in which case it wouldnt cost as much - i think they wear in preference to the bores? However, it may be cheaper and quicker to pull it out and put a 24v in.

[Kevin Bacon 5]

I had exactly this issue- I just pulled the PCV off and cleaned the joins, retightened the clips, and that was that. I wouldn't automatically assume its a symptom of a worn engine as mine uses no oil, keeps its plugs perfectly, doesn't smoke etc. It only takes a few drops of oil to make a nasty smell if its just being left to char itself on the manifold.

 

I think 1/2 litre per 1000 miles is a sign of engine wear, not to mention the amount of oil the OP mentioned is in the intake pipe.

[G-Lad 0]

thanks all, ill definately check the plugs soon. From reading it sounds like cylinders 1 and 6 are most prone to wear. ?

 

Ive been trawling the 24v thread this lunchtime and getting myself ready for a big price tag! Without wanting to plan too far ahead, itd be good to know names of recommended places that would do me a 24v 4 Motion swap, keeping as much standard as reasonably possible, without compromising reliability too much. Stealth are on my list of people to call for a ball park quote..

[fla 9]

naah, wont be that much, especially as you can pick up a 24v block from around £400 or so. From my understanding its much easier to install than the R32 and theres loads of people on here to help you if you get stuck.

Apparently its really not too hard, with minimal teething problems - i too have been contemplating it for months, just need to find the time, place and to sneak it through home security! And thats when my engines only done 66k!

[Abdul 0]

naah, wont be that much, especially as you can pick up a 24v block from around £400 or so. From my understanding its much easier to install than the R32 and theres loads of people on here to help you if you get stuck.

Apparently its really not too hard, with minimal teething problems - i too have been contemplating it for months, just need to find the time, place and to sneak it through home security! And thats when my engines only done 66k!

 

I want dibs on your engine if u do it lol.

 

Im pretty sure psi tuning and the likes all charge around 4k drive in drive out which is hardly cheap! Im sure u could do it for less than half that if u know how though...

[Kevin Bacon 5]

Im pretty sure psi tuning and the likes all charge around 4k drive in drive out which is hardly cheap! Im sure u could do it for less than half that if u know how though...

 

MUCH less.

 

I've got a full 24V setup, including the unchopped loom sat at home which cost me £600 over a year ago. I bought it as a backup engine in case my 12V Turbo let go but the 12V is proving to be stubbornly reliabe and tank like, typical :lol:

 

I'm not trying to boast or anything, but I'm confident I could get that 24V into my Corrado and running as VW intended over a weekend. The ECU harness just needs switched and permanent lives from your existing fuseboard and a few earths. Some of the wires will need changing over for the dash gauges etc and very late 24Vs with the CAN bus rpm signal will need a $60 converter, but it's all easy stuff.

 

The only major additional cost will be a custom downpipe, but I would use the stock cast iron headers and just get a pipe made to bolt onto them. Cheaper and more reliable.

 

It's certainly an alternative to the 12V for sure. Personally speaking, I prefer the 12V. It's what makes a Corrado VR6, a VR6.

 

The 24V's peaky power delivery doesn't suit it at all imo.

[fla 9]

well Mr haywire, i might just buy that off you, if you want to sell it....a very knowledgable friend on here (from up north :wave: ) talked me out of a 24V conversion earlier in the year, but i'm getting a new interest in it again....sorry to clog up your thread G-Lad, hope you get a good conclusion soon.

[G-Lad 0]

 

I've got a full 24V setup, including the unchopped loom sat at home which cost me £600 over a year ago. I bought it as a backup engine in case my 12V Turbo let go but the 12V is proving to be stubbornly reliabe and tank like, typical :lol:

 

I'm not trying to boast or anything, but I'm confident I could get that 24V into my Corrado and running as VW intended over a weekend. The ECU harness just needs switched and permanent lives from your existing fuseboard and a few earths. Some of the wires will need changing over for the dash gauges etc and very late 24Vs with the CAN bus rpm signal will need a $60 converter, but it's all easy stuff.

 

The only major additional cost will be a custom downpipe, but I would use the stock cast iron headers and just get a pipe made to bolt onto them. Cheaper and more reliable.

 

It's certainly an alternative to the 12V for sure. Personally speaking, I prefer the 12V. It's what makes a Corrado VR6, a VR6.

 

The 24V's peaky power delivery doesn't suit it at all imo.

 

Well, if you want the job I might just get back to you to ask your hourly rate ;)

 

if there is anyone in or around the East Midlands with a 2.8 24v in their Corrado who would let me go for a spin, I'd love to see what the experience is like (and have fully comp!). I'd like to know if it's anything like as fun as a 16v mk2 with the extra 2 cylinders of go...

 

RE: the exhaust fitting issues and need for a custom downpipe - is it just an issue down to the cat? I recently fitted a bona fide genuine centre and back box from VW, so would be gutted to not fit that back on!

[dukest 0]

I'd like to know if it's anything like as fun as a 16v mk2 with the extra 2 cylinders of go...

 

RE: the exhaust fitting issues and need for a custom downpipe - is it just an issue down to the cat? I recently fitted a bona fide genuine centre and back box from VW, so would be gutted to not fit that back on!

 

the 12v is more "toppy" than the 24v in the same way that the 16v was over the 8v Mk2s so may give you the opposite sensation than what you're after. that said they are still more powerful overall and the much greater power low down is definitely noticeable compared to the 12v and more used everyday.

 

and yes, the exhaust is just a downpipe issue.

[Ice White Socks 0]

I had exactly this issue- I just pulled the PCV off and cleaned the joins, retightened the clips, and that was that. I wouldn't automatically assume its a symptom of a worn engine as mine uses no oil, keeps its plugs perfectly, doesn't smoke etc. It only takes a few drops of oil to make a nasty smell if its just being left to char itself on the manifold.

 

I think 1/2 litre per 1000 miles is a sign of engine wear, not to mention the amount of oil the OP mentioned is in the intake pipe.

 

1/2 a litre per 1000 miles is undeniably a sign of engine wear- I never said it wasn't? In fact I never even mentioned anything about oil usage :?