Hi all (again),

 

I had a mate who knows a little more about engines than I do have a poke around with the plastic cover off. In the pictures below, you can see there are some damp looking bits (circled) over on the right side of the engine (looking at it from the front, aka: the passenger side of the car, aka: the opposite side to the fuel filter). It looks like it might be a very slight leak from the fuel lines? Or potentially from the tandem pump (that's the metal thing under the braided hose, right?). There is definitely a strong smell of 'hot engine' once the car is up to temp which can be smelt from inside the cabin, outside the car and under the bonnet.

 

Would like to hear anyone's opinion on what it could be, I'm happy to try and get any more photos/run any simple tests if that can shed any extra light? I've also got VCDS if there are any scans I can do that would help the diagnosis process as well?

 

As you can see from my signature (if it shows up) it's a 2.0PD BKD 140, I'm getting pretty decent MPGs still, and the car has had this 'issue' since I bought it second-hand back in November '21.

 

I've done some reading over various forums already and I'm guessing it will either be perished rubber hoses due to age, a gasket going into the tandem pump, or possibly the pump itself (ouch)? I could be way off though with all of those guesses, though.

 

Cheers in advance,

Adam

If you're having problems locating and determining what the leak is, thoroughly wash and degrease the area and monitor thereafter.

Hi,

I have and Octavia 2 from 2009 and since summer I have the same problem.... I checked everything I could but nothing....

 

Roger

Okeydokes, an update:

 

This Easter is turning out to be bloody expensive 🙃😂 The DMF (Dual-Mass Flywheel) has decided to say its goodbyes (the usual horrific rattle that disappears completely the second the clutch is engaged). Additionally, I'm almost certain the tandem pump is goneski as well for two reasons:

1. Strong smell of fuel (I believe) from that side of the engine (RHS as viewed from the front of the vehicle), between the main block and the air intake pipe (?). This is accompanied by generic wetness in the area as well from the limited amount I can see without ripping stuff apart. I'll be asking the garage to take some photos of that side of the engine, as well as the top of the bell housing, when they take the gearbox off to replace clutch + DMF + release bearing + CSC (Concentric Slave Cylinder).
2. Diesel fuel in the oil (again, I believe). I did a spot test onto a standard bit of A4 (Tesco lined if anyone's interested 😉) and a while later got the results shown in the attached photo. If someone could confirm that this is indeed diesel in oil, then that would be great (oil was changed at Christmas by the way).

I'm probably just going to ask them to replace the tandem pump completely and just get it over and done with. Hopefully, this will cure the oil contamination issue which has been going on for god knows how long (no reminders please of the damage this is likely to have caused).

 

If the above doesn't cure that, then the answer will be leaking injectors/seals, I know that much. Don't they usually give issues with starting and smoking though? I have no smoke at all - when cold or otherwise - and no issues with starting at all, if anything it fires up worryingly quick (if that's even a thing).

 

^^ Spot test, oil sample taken from shaking the dipstick.

Okay, another update: DMF & clutch replaced, plus an oil and filter change. Idle is now pretty smooth (smoothest it's been since I've owned the car) and certainly consistent, and no more death rattle.

 

I've determined that it can't really be the tandem pump, it started nice and fast even after being sat (nose higher than tail) for well over a week. From the forum research I've done, that would imply that the fuel system isn't losing any prime, thus the tandem pump is likely absolutely fine. The smell is still there though.

 

The smell seems a bit sweet for oil (unless synthetic does smell a bit sweet?) but smelling around the top of the dipstick when hot is different to the smell directly above the tandem pump. Do tandem pumps just smell slightly of fuel when hot? Like, is it just a PD thing?

 

The oil level is now definitely between min and max on the dipstick so I will be keeping a close eye on that over the coming weeks as well. Also I've thrown in some of that fluorescent dye stuff so that should show up any oil leaks, no matter how minor. One thing to note though is that the oil was black after a 10 minute drive after picking up the car with fresh oil (and after the garage had tested all rattles were resolved). Again, is this a normal PD thing? My previous car (a common rail Megane) maintained nice treacle-coloured oil for ages.

 

The only other things that seem relevant to my smell are:

1. I saw it mentioned in one forum thread that poor (retarded) cam timing caused a fuel smell? I know that mine is -3.9 thanks to VCDS, although I'm probably going to wait until my belt is due next year before I tackle that, given that it's still within official specs... Unless it is likely to cause expensive problems if left until then.
2. It's the injectors/seals, although again I don't get any smoke of any kind under any conditions except for a little bit of black smoke at high RPM under WOT, which I'm pretty sure is completely normal for pretty much any diesel.

Would appreciate if someone could clarify whether I'm barking up the wrong tree, or what I'm saying sounds plausible.