Arrgghhh Major problem...... Help..!!

[Felix.]

Audi A4 diesel 2.4 V8
:1zhelp:
Car has been running fine until yesterday when the glow plug light began to flash.

Carried on for a bit with no bangs, whirls, strange noises of any kind

Suddenly the car stops and won’t start although it does turn over. Looking under the car, there is oil all over the back end of the engine (back of gear box, exhaust pipe etc)

Looking at the oil leak however, it is a mixture of diesel and engine oil (there is no oil in the sump either)

Coolant water is fine and there is no ‘mayo’ on the oil cap

Now the only place I think engine oil and diesel oil come close is the turbo...... Do you think has gone bang..!!!!

Any advice on how to find out – or has anyone else suffered a similar catastrophe :aargh4:

[bez101]

dont think you get diesel in the turbo

[spartacus 68]

Your car is a V6, not a V8. If it was a V8, then you'd have twin turbos, twin inlet manifolds, etc. The 2.4 was a 30v petrol engine? I'm assuming this is a 2.5 TDi V6 lump?

I suspect the timing belt has broken, hence everything is out of sync. Even if the timing belt hasn't broken, it's possibly skipped a tooth (collapsed tensioner pulley bearing, water-pump broken). Pre-2003 cars had cam shaft issues. Early ones had hollow shafts with iron shrunk-on lobes. These lobes split and come loose when worn. A skilled mechanic will be able to diagnose. Keep us posted.

[Felix.]

Right - typed the original in a hurry - it’s a 2.5 V6,

It does turn over still (I know it has no oil, but we are talking mere seconds worth of turning). I wouldn’t have thought it would do this if the belt had snapped.

I'm tempted to clean it all up, put some oil in and see if there's an obvious leak by turning it over again – I’ll check the belt first of course.

I’m tempted to think that this is more ‘outside of the engine problem’ as the coolant has not been affected at all. Although I am perplexed as to why the oil smells strangely of diesel.

[phil miller]

hi mate if it was me id top up the oil level and try again, it is very possible that the ECU detected the lack of oil level and has shut down to prevent failure, now the oil light will only come on if there is lack of pressure you only need about 1/2 lt of oil to fill the oil pump and put the light out, so altho there is an oil leak that needs fixing, my first step would be tpo top up the level and see if it starts if it does then get the leak sorted asap, i dont think this is a timing issue as you said there were no bangs, keep us updated mate

[Felix.]

i will indeed mate


.....and why do these things happen right on Christmas

[phil miller]

i will indeed mate


.....and why do these things happen right on Christmas

i think its called sods law, its the one thing in life you can count on :(

[spartacus 68]

What's the history of this car? It's a 2000 'X' registered AKN 2.5 TDI. Things we need to determine are when was the timing belt changed (should be every 80k including water-pump and tensioner pulley). What oil are you using - ideally a fully synthetic 5w30 viscosity. Still convinced it's jumped a tooth regards the cam belt.

[bez101]

What's the history of this car? It's a 2000 'X' registered AKN 2.5 TDI. Things we need to determine are when was the timing belt changed (should be every 80k including water-pump and tensioner pulley). What oil are you using - ideally a fully synthetic 5w30 viscosity. Still convinced it's jumped a tooth regards the cam belt.
if if jumped a tooth on the belt why would he have lost all the oil ?

[phil miller]

if if jumped a tooth on the belt why would he have lost all the oil ?

i agree, with cars like this it is very easy to jump in at the deep end and condem things without doing the basics, so topping the oil up first and foremost is the first step, plus if it had jumped A tooth it would still start just be very flat when being driven

[bez101]

i agree, with cars like this it is very easy to jump in at the deep end and condem things without doing the basics, so topping the oil up first and foremost is the first step, plus if it had jumped A tooth it would still start just be very flat when being driven
thats what i thought
iv had them jump on petrol and diesel snapped cams and snapped belts
iv never lost oil cos of it

[spartacus 68]

if if jumped a tooth on the belt why would he have lost all the oil ?

Go back to original post by Felix. He's driving along and then the car suddenly loses power and stops and will no longer start, although it will turn over. The V6 takes 6.2 litres (so that's a lot of oil to dump in one go). The obvious things for losing oil would be sump gasket, camshaft or crank oil seal, although not in sufficient quantities to lose it all (unless the sump was damaged). Then there's the diesel smell? Has the fuel pump been damaged. The pump itself can leak as it's under pressure, but a mix of oil and diesel? Sounds catastrophic and expensive, whatever it is.

First thing to do is steam clean the engine bay and determine where the oil leak is coming from. I wouldn't even attempt to fire her up in case the engine siezes. Might be worth using cheap oil for this purpose, then drain. No point using Castrol Edge at £50 a pop to see it all come out again. Also check breather pipes for splits.

[Felix.]

Well... Christmas over

I've put the battery on charge, filled her up with oil and cleaned off underneath having stuck her on axel stands.... then it got dark

I think the leak appears to be more from the passenger side of the engine although I can not see anything obvious. The gearbox and the exhaust pipe had most of the oil on it, but the fly wheel looks to be clean and the clutch was not slipping at all before she stopped.

There has been no oil leakage so far, but I’m going to turn the engine over tomorrow and see what happens.

[nanndy]

give us a holla if need any engine bits

[spartacus 68]

Yep, keep us posted... this one is intriguing.

[Felix.]

Had a go at starting her up.

It won’t start - but everything seems to be moving as it should, looking into the oil filler port, I can see the cam moving, so I’m happy the timing belt is OK

The car is full of oil, but after a while the ‘flashing oil sign’ comes on. Now I know this is low oil pressure but there is nothing leaking out of the car so far.....?

[Felix.]

Here's a weird thing as well, the windscreen water warning light comes on as well, eventhough its full....?
And the water washer pump is not working, but the wipers do - so not a fuse issue

[nanndy]

any water in the box on the left hand side where engine loom goes into?

[Felix.]

ECU box...?

Yep, dry as a bone

[Felix.]

Right.....

Topped the oil up and nothing has leaked out.

Took the two rubber fule lines off the fuel filter and tried to crank the engine. Nothing came out of either. One will be a feed and one a return - so can i assume the fuel pump has gone....?

If so where is it. Is it in the tank or is it the thing at the front of the engine with the 6 pipes coming from it to the cylinders

[Felix.]

Right then...

Found the pump (at the front of the engine so re-adjusted my test.

Took of the two pipes pump side of the filter and dipped the ends into a jar of fresh diesel. Still would not start, but I could see movement in the jar, so i assume the pump is doing something..

Took the metal breather pipe off and cleaned out underneath the pump, liquid here was diesel which I think was the leak from the car in the first place, but the underside of the fuel pump is dry and so are the connections.

Is there a pressure valve (or similar) in the pump, so that if the filter is blocked, it can push out the fuel somewhere...?

Battery went flat so it’s back on charge and I’m going to try again tomorrow. Could this be an immobiliser/car safety feature which has kicked in and is now preventing the car turning over...?

[Felix.]

Hoorray :fest30:

Got it back working. Turned out to be the tank fuel pump. £25 second hand one from e-bay. Bled the system and hey presto.... The fuel gauge was bouncing up and down for a bit though which seemed strange, but seems to have settled out.

I think what happened was the weeper pipe from the injector split and air was introduced into the return system. This seems to have upset the pump (or it was on its way out in any case). So, no returning diesel ment the baffle ran dry inside the tank - hence the car stopped.

Fantastic noise of engine starting again....... :banana:

[Felix.]

The other thing. The other electrical part of the sender unit has a float on the bottom...?

Anyone know what this is....?

I assume its the engine cut off - so if the tank runs dry, it stops the engine before air gets into the pipework..