Low Oil Light but Oil Seems Fine?! Help Please!

[Springer*]

Hi there,

Strange thing happened at the weekend as I drove my 2003 Audi A4 1.9 TDi PD130 Quattro Sport down to London from Leeds.

Car drove fine but roughly 100 miles into the journey I was greeted by a warning bleep and a low oil warning on the electronic display (yellow oil can)

The oil level is regularly checked along with the other fluids and in nearly 4 years of ownership I have never known the car to burn much oil or have any serious leaks. I carry out oil services myself annually and with the correct PD-spec oil too.

Anyway, when I pulled into the nearest services and checked the dipstick (on a warm engine obviously) there didn't appear to be any oil level at all. Am I right in assuming though that because the engine was warm that I wouldn't get a normal reading from the dipstick?!

I therefore purchased a litre of (extortionately overpriced ) VW-spec 5w 30 fully synthetic oil and put it in.

After setting off again the oil light stayed on but went out again after about 20 more miles.

I drove the car back up to Leeds again that evening covering 390 miles in the day and on the way back the car drove perfectly.

The following day I checked the (cool) oil level and it gave a perfectly normal reading half way up the dipstick, which seemed strange because if the oil was really low the day before, a litre of oil from the services wouldn't have filled it up to halfway, and also if there was no oil loss and the warning light was just an electrical gremlin, then surely the oil dipstick reading the following day would have been high?!

Either way, I'm rather confused and worried about some form of imminent oil pump failure or leak etc.

Could anyone shed any light on what could have caused this sudden apparent oil leak? Or if this is a common glitch on older cars?

Finally, one last thing is that I think my EGR is on its way out and has been leaking a bit of oil vapour over the last 18 months or so. I'm not sure its enough to have caused this though.

Any help would be much appreciated

J

 

[john777w]

Shouldn't it be at the top of the crossed-hatch area of the dipstick??

 

[Mike B]

Yes you should have had something on the stick even when the engine is hot.The level must be within the hatched area at alltimes.However it couldn't have been critical cos the litre has given you a decent level.The question is when did you last check before this what was the level and how many miles since?If its suddenly started to use the oil then you need to find out why.these engines are so solid I would guess something to do with the turbo.What does the exhaust look like?Perhaps you could just wait and see what happens to the level if it appears normal but if the light comes on again it will become urgent so I wouldn't risk another long trip until you know more.whats the mileage?Some older cars do use some oil but the increase should be small and steady.My 2.5tdi 03 on 120k hardly uses any but our 1.8T is just holding to the Audi guide of up to 1ltr per1000km on 130k but I think that's right for that engine .

 

[Springer*]

Thanks for the replies.

Mike,

I checked the level probably 300-400 miles ago and it was fine. This was probably 2-3 weeks ago.

The car is on 137,000 miles and I've owned it since 2011 when it had 94,000 miles under its wheels.

About 18 months ago I had the EGR and Intake Manifold completely stripped down and cleaned by a VW/Audi specialist. I had the EGR blanked off at the same time too. The EGR was in a pretty bad state and was more or less totally blocked but the Intake Manifold was gunked up, but not as bad. I did the EGR blank to stop the sooting up starting again.

There have never been any issues with the turbo up to now and I've not suffered from the sticking turbo vanes like so many have with cars of this age.

Upon start up when cold the car can puff out quite a large(ish) plume of blue(ish) smoke but once this clears its hardly smoky at all. Well no more than any other pre-DPF diesel car anyway.

The exhaust has always been fine and even though slightly sooty at the ends (its a twin being the Quattro) its no more so than any other diesel of its age.

Its due its annual oil service next month and so I'll ensure all levels are as they should be then and in the coming months I'm due to get the cambelt and waterpump changed and tensioners checked etc.

I think I will just keep an eye on things for now but naturally I hope its not the turbo on its way out. The annoying thing is that I need to drive down to Surrey from Leeds next week and could do without this lol!

Any ideas?

Cheers,

J

 

[Mike B]

Is it possible it may not have been on the level when you checked?All you can do is watch it and hope its a oneofI think you would notice if the turbo was failing.I would stop on the way down just to check the level if you have chance.

 

[Mike_B]

Oil level sensor? Known to go bad, and certainly did early in the life of a B7 I had back in the day. If the car's going in for major work soon anyway, might be worth having it changed at the same time?

 

[Mike B]

But he has had to put in a litre after only 400miles so wheres it going?

 

[hades-]

the dip will show low or nothing when the low oil light comes on a ltr will top it up
the light comes on when its 1 LTR down.

the dip stick isn't for the full 4.5 ltr

 

[Mike_B]

Well, I guess the only real solution is top it up (cold / level) to the "full" mark on the d/s - then monitor, perhaps also letting it run to the point where the warning light illuminates and then top off again. Works for me anyway, combined with checking the oil every week (!!!) and using the trip to cross-check as well. That's how I know I need a ltr every 1,000 miles or so, which is well within limits even for a car with 135k on it. Mind you, my old Mondeo didnt use as much. Just saying

 

[Mike B]

Agree hes got to watch it closely but understandably his concern is why its suddenlydropped a lot after a long time with no bother.Just shows it pays to check things regularly and not rely entirely on these warning lights.

 

[Mike_B]

This is true, Mr B - nowt to beat the old ways, before these new fangled gizmos came along - - that said, I find it hard to get a reading on a d/stick on a hot engine, so maybe that was part of it?

 

[Darran]

The large plume of blue smoke when you start up is 1 of 2 things......
1...Air leak on the fuel line somewhere.
2....Valve stem oil seals weeping abit.
Let the car tickover for 10 mins then get someone to give it a good rev IF you get the blue smoke and then it clears then its valve stem seals and personally i don't mind them weeping a small amount as it pre lubricates the bores.

If it were turbo seals then you need to check your inlet pipe to the inlet manifold (air pipe from intercooler) if its full of oil then turbo seals are leaking. Hope this helps.

 

[Springer*]

Thanks for the replies peeps. A great help!

Just given the car a clean and a spruce up prior to my trip down to Surrey tomorrow morning. Checked all of the fluids and all seems fine so far.

The brake fluid was a little low in the reservoir so I've topped that up, coolant where it should be, oil level hasn't budged since I topped it up, so hopefully all is okay for now.

Will certainly do the tests for valve stem and oil seals when I have some time.

Still really mystified as to why the oil level dropped over a couple of weeks but will certainly keep a much closer eye on things from now on.

J