Thread: 300 Tdi Tweak

Originally Posted by Leo109

Hi Rangieman,

From your mention of "Stage 1", it sounds a bit like the Tdi tuning notes I wrote a couple of years back that I believe are still linked on this site somewhere? (Never bothered looking for them, 'cos I've got the originals!).

If so, I hope you found them useful. If not, I'll now crawl back into my burrow...

Totally "Off Thread" but we (the Thermoguard Global Headquarters, R&D and Logistics divisions (aka: my good lady, me and the cat, in the caravan) arrived in Tassie this morning. Were off to enjoy the Bay of Fires, hopefully before every Lonely Planet reader gets there, tomorrow. Then, as soon as possible after that, we'll drop in and try to annoy Justin C as best we can. Sorry for hi-jacking your thread...

Ian P.

Yes ian it sure is from your notes , i down loaded them a couple of years ago and have only now been game enough to try it out
Thanks mate

Originally Posted by dullbird

thats strange becuase it did on our 200tdi.....a mate tweek ours up on the way to the fench alps as we were struggling to keep up wioth people. the car went like **** off a shovel when done but we got alot of black smoke to go with it to..on gear changes infact everyone I know that has done it gets some smoke.

because aren't you increasing the amount off fuel being delivered to the injectors? or have i got that wrong...i thought that was were the black smoke came from it was just excess from effectivly overfueling hence the power

The adjustment screw on top of the boost compensator, adjusts the fuel when there is no boost pressure.

As boost starts to build, the pressure acting on the diaphragm pushes the sliding pin and control cone down away from the adjustment screw - so the adjustment no longer plays any part (until the boost pressure drops back to nearly zero.

The gain that you notice when adjusting this screw in is the turbo boost builds quicker when you take off from stopped - because it provides more fuel at no boost, there is more heat in the exhaust gasses to get the turbo spinning.

It want give any improvement after you get going, or on hills etc, as the turbo will be providing boost then.

If you experienced a problem with excessive smoke after this adjustment, then it was screwed in too far.

If you experienced a problem with engine braking, then again, it was screwed in too far, and increased the idling speed.

Just to reinforce what I have said, for others. This adjustment on helps with pulling away and only when the turbo is not making any boost.

IMHO, (as I posted earlier) the first adjustment should be to the rotation of the control cone. Then when you have the full load adjustment right, you can adjust the screw above the sliding pin to get the smoke right when taking off at low boost.