smoke issue 1.6tdq

[Tonis506]

I have a mk2 jetta, it has a 1.6td with a what I believe is a na pump. It doesnt have the canister on top just the post for the return lines. There is like a whiteish Blue smoke that smells like fuel at idle and underboost it goes away. The valve seals are good I just had the head checked for everything and it was fine. The car runs great mad has power. The exhaust is a downpipe and that is all but that wouldnt have anything to do with it. Any suggestions I am new to diesels and I just put the motor in this car.

[8v-of-fury]

The timing is too far retarded. You must advance it. The smoke goes away while under boost or under way because the pumps internal advance takes over and advances.

Answer me this, does pulling the cold start make the smoke go away at idle?

[Tonis506]

The timing is too far retarded. You must advance it. The smoke goes away while under boost or under way because the pumps internal advance takes over and advances.

Answer me this, does pulling the cold start make the smoke go away at idle?

The cold start isnt hooked up. When I work on the Car tonight I am going to retime the pump, make sure its in spec. And try to reach in there and move the cold start assembly.

[TylerDurden]

Another clue to determine if it is timing, is whether the engine clatters when cold, or not.... No or little clatter when cold could support the notion that the timing is too retarded. (Constant clatter when warm could be too advanced.) A timed engine will clatter when cold and not when warm.

Timing to spec may be a good start when everything else is spec, but if the injector break-pressures are high, the timing might need more advance.

Some folks time the IP "by-ear", setting the pump to the cusp of clatter at idle when the engine is warm.


Smoke with a TD can also come from overfueling, boost at higher rpm will reduce that smoke (that's the reason for the extra bits on a TD pump... reducing fuel at low rpm until boost builds).