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Air in diesel fuel line Help!

Hello,

I have driven audi 80 TD on reserve diesel till it started missing. Then I have tanked but it started giving white smoke. I thought that filter is full of dirt so I changed the filter then I noticed that there is air in the lines so today I changed all rubber lines from filter to the pump but still I can see air in the lines and the white smoke is there.

My Qs is, Is it injector which is letting air? car is rough with reduced power and I already tried the injector cleaner with the fuel but so far no effect.

I also tried losening the diesel intake on the injectors to check if no RPM reduces then I can spot the faulty injector but all injectors effect the RPM so I guess they are partially working.

What shoud be the next thing to check? It was all ok before I drove to empty tank.

Any tip is much appriciated.

Thanks

Reply to
chilldown
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Did you fill up the new filter with diesel fuel before you installed it? Skipping that step in itself would create a fairly large air pocket.

Reply to
Madesio

I opened the filetr twice after that and yes I filled the filter everytime. Somehow I noticed that vacuum is not building up.

Reply to
chilldown

I have a hard time understanding you, but from what i gather this happened only after you filled up the tank? Your model is a little old but most TDI's came equipped with an in-tank fuel transfer pump with a check valve that often times became stuck open. It would also help to rule out any damaged parts of the tank and lines up to the belt driven pump that would be pulling in air as the pump runs.

Reply to
Madesio

The fuel system needs bleeding. ( bleeding means letting the air out ) Look for the highest point on the fuel line, there may be a bleed screw there. On older diesels it is not a difficult thing to do, it was not always necessary to have pressure in the system other than gravity. New eng' fuel systems may be different and the system may need to be pressurised and pressurised back to the pump to remove air in the pump(s). One way may be to have the engine running and start at the furthest injector from the fuel pump or filter, bleed that one and work your way back to the nearest injector to the pump. Opening and closing the connections one at a time, waiting about 5 secs between opening and closing the connections. You may need to do this several times. You shall need something to soak up or catch the fuel in.

Reply to
neeoup

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