MK1a - Oil spotted where it shouldn't be

[System-G]

Last week shortly after getting my MKI and just before sending it for an MOT, I removed the air filter to check how clean (or dirty) it might have been and saw oil on the intake pipe side of the filter

Car was due a service with cambelt change at the same time, so I wiped clean the filter and replaced it. Service didn't happen because of MOT failure issues eating up service budget (and because I'm not really driving the car much at all, the service can be done next week.

Today I remove all stock air box items, filter, tubes and pipes to fit an induction filter. I notice on removing the bits that the entire intake pipe is heavily coated in oil. But there was no sign of any oil in the entrace to the TVIS thingy (throttlebody?).

Now:
1] I know this should not be normal.
2] How the F k did it get there?
3] Is it possible my engine ispropper F ked
4] Exhaust doesn't smoke.
5] very minor traces of "mayo" in oil filler cap - but normal - my corolla GTi got it when not driven frequently.
6] No sign of oil in water/coolant system.
7] Engine sounds and runs fine.
8] A fair bit of oil spillage on cam covers.
9] Dipstick level reading above max mark (not much though)
10] No oil on the outer side of the filter.

Any ideas anyone?

[MegatronUK]

I'm not too great on the 4AGE, but if there is a breather from the crankcase or head attached to the intake, and if too much oil is in (as you've described), then you would definitely get some coming through the breather and into the intake - a small amount is normal, especially on something as old as a mk1.. but I'm talking a fine coating, rather than an amount which would pool.

Check all the breather hoses from the crankcase and the head... on most cars they can block with oil deposits with age and cause pressure to build up, forcing the vapours and oil to choose the path of least resistance - it's normal for most cars to get these vapours from pressure inside the engine, but usually they just go back into the intake and then burned during combustion.

[Lauren]

I'm not too great on the 4AGE, but if there is a breather from the crankcase or head attached to the intake, and if too much oil is in (as you've described), then you would definitely get some coming through the breather and into the intake - a small amount is normal, especially on something as old as a mk1.. but I'm talking a fine coating, rather than an amount which would pool.

Check all the breather hoses from the crankcase and the head... on most cars they can block with oil deposits with age and cause pressure to build up, forcing the vapours and oil to choose the path of least resistance - it's normal for most cars to get these vapours from pressure inside the engine, but usually they just go back into the intake and then burned during combustion.

The PCV is after the throttle body though so its unlikely its that tbh.

[Lauren]

Do you get blue smoke out the exhaust when you lift off at high rpms?

There shouldn't be oil on the intake, particularly on the induction side of the throttle body.

When my rings went on my old NA i got oil dripping out of the airfilter!

Just keep an eye on it is about all you can do really.

[System-G]

No blue smoke at all...

There is only the white type of "smoke" when the engine is cold - which is normal for this type of weather. Once the engine is warm no smoke at all

I think I'll wait to find out my mechanics verdict once it's gone in for a service and update this thread... In the mean time I hope something doesn't go bang

[Lauren]

No blue smoke at all...

There is only the white type of "smoke" when the engine is cold - which is normal for this type of weather. Once the engine is warm no smoke at all

I think I'll wait to find out my mechanics verdict once it's gone in for a service and update this thread... In the mean time I hope something doesn't go bang

I wouldn't overly worry about it tbh. If its going to go bang it will etc..

Its not using any coolant is it? I'd honestly say though i wouldn't worry unless oil was dripping out of the air filter as then you would definatley have a problem, though you'd notice it elsewhere first in all honesty!

[BenF]

Last week shortly after getting my MKI and just before sending it for an MOT, I removed the air filter to check how clean (or dirty) it might have been and saw oil on the intake pipe side of the filter

<snip>

Any ideas anyone?

I had a major brown trouser moment driving around Bruntingthrope at MR2004 when I saw clouds of smoke coming from the engine bay of my MK1a. After stopping near a marshall and having a look in the engine bay you could see oil had leaked out and was boiling/burning off the exhaust.

After thinking the worst (HG / Cracked block etc) in the end it was quite simple - I tracked it down to loose cam covers!

When they're loose, oil can leak past at high RPMS and get eveywhere ..

[System-G]

I tracked it down to loose cam covers!

When they're loose, oil can leak past at high RPMS and get eveywhere ..

I could understand that, but inside the stock airbox and on the throttlebody side of the filter and in the air intake pipe?

Engine is clean in comparison to a lot of MKI's (and MKII's) I've seen - bit's of oil top-up spillage here and there, but generally quite clean.

Incedently, I ran the car up on my drive with the filter and air intake pipe removed. Just to see if any oil was spurting from the throttlebody - none. Just very thin whispy clear white "smoke" that looked like exhaust fumes and smelled a bit petrol-ly. It only appeared after backing off the throttle. There was no "smoke" or smell when throttle was open (sucking air inwards)...

[System-G]

I had to drop my car into my mechanic's place as a matter of urgency as I was being overwhelmed by the smell of fuel in the cabin and got quite worried (details of this in another post).

Had a chat to Richard (my mechanic) who said it was likely if the engine was over filled with oil the easiest way out is the hose in the photo which goes between the cam cover and the TVIS "thingy".

We are not 100% certain that the oil in the air intake pipe came from the hose but it's very likely. He also sugested keeping an eye on it to see if oil re-appears, if so then we could be looking at something else entirely.

Photo of the hose:

[System-G]

Bad news.

The oil is back in the air intake pipe
In fact it's dripping out the end of the induction filter now

The oil level on the dipstick is still a tad high (about 1mm above maximum mark). The only way I can think of oil getting into the air intake pipe is through the hose connecting the throttle body and cam cover (pictured above).

The car is going for it's service and cambelt change next week. I suppose I will have to monitor the oil getting to the air filter after the service.

If oil continues to get into the air intake side of things I suppose an oil catch can will have to be fitted between the cam cover and throttlebody, unless someone has any other idea of how the f k it's getting in there

Oil pressure gauge is opperating normally and temp gauge is normal too. Engine sounds fine but is a bit lumpy on idle.

Will keep post updated

[MegatronUK]

Thats exactly the breather hose I was talking about in my reply. Your engine is building up pressure for some reason and the result is that oil is being forced out there. Probably due to a combination of reasons - too much oil, and the other breather pipes being blocked.

I'd try a couple of things:

Take ALL the breather pipes off, not just that one, and clean them all through with petrol, thinners or similar, making sure they are free of blockages. Obviously do it one at a time, so you know where they go back !

Drop the oil and replace the oil filter and refill with oil to below the dipstick upper level. Running a car with the oil midway between the two marks on the dipstick is perfectly fine.

That should clear it.... if not, then there is something more serious causing the pressure to build up, and you'll have to investigate more deeply.

ps. technical term for that 'tvis thingy' is the plenum chamber

[System-G]

Take ALL the breather pipes off, not just that one, and clean them all through with petrol, thinners or similar, making sure they are free of blockages. Obviously do it one at a time, so you know where they go back !

That was going to be my next port of call

Drop the oil and replace the oil filter and refill with oil to below the dipstick upper level. Running a car with the oil midway between the two marks on the dipstick is perfectly fine.

The car is going in for it's full service and cambelt change with my local independant specialist this week coming. So will get him to check everything. Car is running extremely rich (see my other post about fuel smell in cabin). Not only am I still getting a slightly fuely smell in the cabin, but I on got 180 miles out of 3/4 of a tank of fuel I'm not new to 4A-GE engines and I know that is a bit excessive

ps. technical term for that 'tvis thingy' is the plenum chamber

Excellent! Always good to know


Thanks a lot for all you info mate =D>

[Lauren]

Bad news.

The oil is back in the air intake pipe
In fact it's dripping out the end of the induction filter now

The oil level on the dipstick is still a tad high (about 1mm above maximum mark). The only way I can think of oil getting into the air intake pipe is through the hose connecting the throttle body and cam cover (pictured above).

The car is going for it's service and cambelt change next week. I suppose I will have to monitor the oil getting to the air filter after the service.

If oil continues to get into the air intake side of things I suppose an oil catch can will have to be fitted between the cam cover and throttlebody, unless someone has any other idea of how the f k it's getting in there

Oil pressure gauge is opperating normally and temp gauge is normal too. Engine sounds fine but is a bit lumpy on idle.

Will keep post updated

Do a compression test. Am worried its your rings. The oil being slightly overfull won't cause this so its not that. Let us know how it goes.

My first 4AGE had oil dripping out of the intake accompanied by a lot of blue smoke on the overrun, in the end it wouldn't idle and i put it down the rings going.