(No more) Soot and dirty oil building up around glowe plug

Fredaudi

A2OC Donor
Good evening A2 friends!
Yesterday I had an inspection under the enginecover and found a thick layer of soot and dirt near the glow plug, and around the corner of the engine.
Is this a leak from somewhere, or is it just a place where dirt builds up over time?
I tried to hear, and look for leaks, but could not find any source for it.
Anybody with a theory?
 

Attachments

  • 6F6114E2-9CD6-47BA-BFFE-ACB10D3E81DA.jpeg
    6F6114E2-9CD6-47BA-BFFE-ACB10D3E81DA.jpeg
    519.3 KB · Views: 167
No theory but I'd give the area a thorough clean then check for staining after a run. If it's a compression leak it will show up straight away

Cheers Spike
 
Last edited:
Thanks everyone, great suggestions.I gave it a good clean, and had the glow plug out.Its not from that.
The build up was mostly under the plastic thing(..) with wires going into the top, this is a place where the engine top cover - do not cover too good, so my first guess was that it was a place for turbulence of soot and oil to build up.
I give in a week or so, and then check again.
In the mean time I will google tandem pump, injection looms and rocker gaskets..
 
After clean up. Better picture.
 

Attachments

  • 6A62FAEC-A80B-4C27-A971-4B0B54D815ED.jpeg
    6A62FAEC-A80B-4C27-A971-4B0B54D815ED.jpeg
    740 KB · Views: 135
I am somewhat surprised we don't see more leaking in that area, but again it does not have much pressure by that loom I guess?

It has an O ring over there and fairly easy to replace just need to be careful to not break connectors - need to take rocker cover off though it would have a bit of wiggle room with just undoing the 2 bolts and move it back and forth to give it a bit of a clean.

Not sure on the O Rings spec but replacement loom is not terribly prices either from memory.
 
I agree, if it was the injector loom o-ring, I guess the build up would be all around it.I will give it some days, and see where, and if, a new build up starts.
The leak might be small, and the build up came over years, so its a bit tricky to determine.
Maybe I should do a compression test?

 
Last edited:
I have actually had a look at my 1.4 AMF and it also has a considerable build up of oil in the same spot. It is definitely oil and all of the mess is radiating around that injector loom connector. It can't be a very big leak though because I am not really noticing any oil consumption (oil still at the top end of the dipstick measurement 3,500 miles after the service). Will be interested in further developments.
 
Update.
Am I starting to see a bigger problem here?After I found the soot and oil build up around and under tandem pump, I took off the undertray of the car and found more oil from somewhere.A bracket supporting the hose to the intercooler was broken off, and there was fresh oil from the lower part of the intercooler, on the hose, and at the undertray.
Could it be a link between the two?That the source is the same, and it only looks( from above)that it is from around the tandem pump and the glow plug area under?


After a closer inspection, I think its the tandem pump gasket, that has a small leak.
The Bosch F009 D02 799 with OEM number 038 145 209Q needs modifications to fit BHC engine, if I understand it right?
What other options exists?
Order a new aftermarked pump, OEM gaskets form Audi, or one of the gasket repair kits?
I would want to make a replacement that lasts.
One other thing, the pumps shows up as a part of the brakesystem, maybe this can explain why my brake pedal sinks a bit, when high pressure is applied standing still?
(No leaks or air in the brakesystem)
 
Last edited:
Yes the Bosch pump will need an additional spacer to clear the ASV on the BHC and ATL engines. It is a better pump than the LUK pump. Saying that the LUK was fitted from the factory and lasted this long, so you could just fit another LUK without any modification.

Choice is yours either Bosch or LUK, either way you need a quality OEM gasket which usually is not included with the new pump. Do not buy trhe pump from Audi, do a search and find one at a good price. As for a repair kit, do not waste your time and money.

It is called a tandem pump because it is two pumps in one. It is a high pressure fuel pump and a vacuum pump.

Your brake issue may or may not be the tandem.
 
Can you post a picture of your ASV showing the pipes. Reaso I am asking this is on the LHD AMF engines the air pie enters the EGR from the left side and is nowhere near the tandem. Just need to see if on the BHC LHD cars if it routes to the right i.e. past the tandem or if it also routes to the left..
 
I would prefer Bosch, and it appears as a BHC-fit; in some lists.The LUK pump is not so easy to find new either.
Different car repair shops did a bleeding of the brakes, but the brakes are not like they used to be earlier.
Would be great If you could confirm that the Bosch is a fit.
ASV is on the opposite side of the tandem pump here.
 

Attachments

  • 540D14A7-960E-436D-9771-2102EE4A2BB1.jpeg
    540D14A7-960E-436D-9771-2102EE4A2BB1.jpeg
    943.7 KB · Views: 115
Last edited:
That is good news for your LHD car. They have done the same as the AMF engined LHD cars. So you will NOT need the extra spacer to clear the ASV and the Bosch tandem pump will be a direct replacement to your existing pump. Just make sure any brake pipes or rubber pipes are still giving enough clearance to prevent frettage and chafing.
 
Wunderbar! A new shiny Bosch pump is going in.Hard to find out, if the Bosch F009 D02 799 comes with a gasket or not.With even more luck, the mysterious brake issue will cure!
The list of concerns are going to go to zero soon..
 
Last edited:
From my experience Bosch does not supply the gasket with their pumps, but some retailers bundle a gasket in the sale of the pump. Best to check if they do otherwise order an OEM quality gasket ( one with the 2 little blue tracts of silicone ).
 
A gasket could be a delicate thing, should be OEM I guess." one with the 2 little blue tracts of silicone" Great!
Still, I do not understand how the braking system is involved.The Bosch pump is a part of braking system.Playing the 3rd violin in the tandem 2 pump trio then..
 
Last edited:
The tandem pump is two pumps in the same housing. One part supplies the high pressure fuel by sucking it from the fuel tank and sending it to the injectors, the return surplus fuel also passes through the tandem on its way back to the tank. The second pump is a vacuum pump, as the diesel has little induction vacuum. This vacuum supplies the brake servo and also any vacuum operated valve or switch on the car. A common often unnoticed failure of the tandem is the spigot on the rear that supplies the vacuum becomes a loose fit in the tandem housing. This causes havoc with the vacuum, even worse if it is just loose enough to seal every now and then to produce full vacuum again only for it to leak away as the spigot vibrates again.
 
Cool, thanks for your involvement.I do not understand how the tandem pump supplies vacuum to the brake servo or other valves yet, but the brake servo has been mentioned every time I have serviced the brakes.
Does the brake servo depend on vacuum from the tandem pump, or is it more of a support?
Spigot!
I hope the spigot problem is a never returning ghost with a new pump..
 
Back
Top