fuel adjustment screw

[jpliddy]

hi all is it ok to adjust the fuel adjustment screw at front of the injection pump behind the I.P. pipes
i would like to reduce the fuel a little as its a bit smokey unburnt diesel?
i have never touched this screw in all the 16 years i have owned my 940 tdi 1995
all comments most welcome

[ngoma]

Sure, easy to experiment. Mark the starting position so you can easily return it to your baseline if you encounter any problems. Try testing 1/4 turn increments and see where that gets you.

Although, since your car is turbo, depending on the specifics of excessive smoke behavior, the problem might lie in the LDA or its adjustments. Does it smoke at idle, off-idle, cruise, high RPM/high load?

[jpliddy]

hi
car only smokes when cold at take of and some times when i put foot down to
car is only returning about 28mpg now but thats with no long runs.
no smoke when warm but when i start up when hot it leaves a splatter of black soot from exhaust on the ground so I'm thinking this is unburnt diesel
what do you think ?

[jpliddy]

hi ngoma
what does L.D.A. mean

[ngoma]

Originally Posted by jpliddy

what do you think ?

Sounds almost normal, from your description.

LDA is the flying saucer-looking device on the top of the IP. Cuts extra fueling at low turbo boost conditions, sends extra fuel at higher boost conditions.

[jpliddy]

hi ngoma
thanks for your input.
but the splatter of soot is not nice have you seen this before.
so do you think leave well alone

[ngoma]

Can't say, based on your description. Could you have someone take some photos?

[jpliddy]

thanks again for your input Nogma i will leave it for now as i have M.O.T. on
saturday morning 1st thing at 21 years old will be crossing fingers that it gets through ok but we never know what they will find will let you know how i get on
regards jim