VWDiesel.net The IDI, TDI, and mTDI source.

Engine Specific Info and Questions => IDI Engine => Topic started by: Infinitrium on July 10, 2008, 05:31:27 pm

Title: Can the fuel screw be turned out too far?
Post by: Infinitrium on July 10, 2008, 05:31:27 pm

I was adjusting the fuel screw earlier, I turned it almost 1/2 turn counterclockwise then tightened the nut back up and took it for a test drive. Definitely much less smoke now, almost nonexistent, and it even seems to run a bit cooler too. I think as it is now, it's turned a bit too far out. There seems to be a flat spot on acceleration at lower speeds until the turbo gets going. Is it turned out too far? Will that do anything bad to the engine being like that? I am considering turning the screw 1/4 turn clockwise to see if the low speed acceleration flat spot goes away.

Title: Can the fuel screw be turned out too far?
Post by: jtanguay on July 10, 2008, 06:12:46 pm

turn the idle screw in a little bit.  or is it out???  :lol:

Title: Can the fuel screw be turned out too far?
Post by: Infinitrium on July 10, 2008, 06:40:54 pm

Oh boy, idle screw? Heh, pretty sure I didn't touch that one, I don't even know where it is.

Title: Can the fuel screw be turned out too far?
Post by: Smokey Eddy on July 10, 2008, 11:06:46 pm

it's the screw that the ... i dunno what you'd call it ... throttle body? rests on ... makes sense dun it??? its the same as your max throttle screw but on the opposite side of course

Title: Can the fuel screw be turned out too far?
Post by: jtanguay on July 11, 2008, 03:24:36 am

when you increase the fueling with the max fuel screw, the idle will rise/hang.  to compensate you (un)screw? the service idle screw.  the same applies when reducing the fueling  (reverse the direction of the service idle screw) :wink:

its located behind the pump closest to injector no-1.  there is a 10mm locknut that needs to be loosened, and you'll need a thin flat head to turn it.  if it hasn't been turned in a while then spray it with some penetrant, but don't go spray happy on it... unless it doesn't react with any seals/rubber etc.  then go nuts  :lol:

Title: Can the fuel screw be turned out too far?
Post by: regcheeseman on July 13, 2008, 02:40:43 pm

Quote

Can the fuel screw be turned out too far?

Yes, struggling to get mine through emissions test I wound the screw out too far - It breezed the test but was absolutely flat as a turd - no power or acceleration but would get to up to speed eventually.
Had to stop on a steep hill and it was a struggle to restart and then would not pull 2nd gear.

I twizzled the screw back out to max smoke as soon as I got home.

Title: Can the fuel screw be turned out too far?
Post by: FWD.MOTION on July 17, 2008, 03:55:50 pm

how do you set the idle without the rpm gauge....or know if your engines running too fast/slo? how can one know

Title: Can the fuel screw be turned out too far?
Post by: Black Smokin' Diesel on July 17, 2008, 04:28:08 pm

Quote from: "FWD.MOTION"

how do you set the idle without the rpm gauge....or know if your engines running too fast/slo? how can one know

Go by ear. Idles gets really lumpy if it is too low. If the engine rattles quite a bit, turning up the idle a bit works good to reduce cabin vibrations.