Need more fuel under boost....

[turbotor]

Maybe I should take a picture of my home made LDA pin, its conservative like the stock pin off boost and allow max fuel under boost.

my engine idle at 900rpm, light smoke before turbo spools up then 0 smoke but it pulls great. the fastest IDI diesel in my town  :wink:

vwmike: do you sell seal kit to the pump? I did see that i have a very smal leak at the fuel screw.

[DVST8R]

Well small leaks, and bubbles in the fuel system are deffinatly holding you back. Does it cause it to miss at all?

Get the pump sealed up, the filter changed, and make sure the bubbles are gone. If you are still not getting thick black smoke even at 15psi, I am stumped, but will continue thinking it through.  :wink:

[turbotor]

Well small leaks, and bubbles in the fuel system are deffinatly holding you back. Does it cause it to miss at all?

Get the pump sealed up, the filter changed, and make sure the bubbles are gone. If you are still not getting thick black smoke even at 15psi, I am stumped, but will continue thinking it through.  :wink:

It doesnt miss...maybe a little(first 30 sec) when it`s very cold utside.
Going to change filter tomorrow and see if I can find a sealing ring(o-ring) to put on the fuel screw.

[vwmike]

vwmike: do you sell seal kit to the pump? I did see that i have a very smal leak at the fuel screw.

I'm sorry, I don't  

I really ought to look into that.

[turbotor]

I have changed filter and that plastic valve on top of the filter....and airbubbles are gone!! and best of all car pulls better  
....its dark so I didnt see any smoke  :wink:

BUT on one side of the pump there is a adjustment screw, and when I look inside one of my scrap pump I can see that this can limit the travel like the boost pin. What is this for? :roll:

[turbotor]

I have changed filter and that plastic valve on top of the filter....and airbubbles are gone!! and best of all car pulls better  
....its dark so I didnt see any smoke  :wink:

BUT on one side of the pump there is a adjustment screw, and when I look inside one of my scrap pump I can see that this can limit the travel like the boost pin. What is this for? :roll:

ehh, opposide the cold start.

[zagarus]

so what does adjusting this screw do (in red)?



oh and where is the fuel pump?

[RabbitJockey]

that changes how much fueling you get when you have the pedal to the floor, i think.

[zagarus]

thats not gonna give me more fuel is it?

[malone]

thats not gonna give me more fuel is it?

That screw is called the "max throttle screw" if I remember correctly.

While the engine's turned off, get a friend to hold down the accelerator pedal while you look at the fuel pump. If you see the throttle lever (that swings when your friend hits the pedal) easily touch the max. throttle screw, then that means there may be room for the lever to swing further - yes this will mean a little more fuel for you.

Loosen the tightening nut on that screw with a wrench and then back the screw out by turning it counter-clockwise with a flathead screwdriver.

Without needing your friend's help swing the throttle lever as far as it can go with your hand (until it cannot swing any further) and then set your screw there.

I have seen some people completely remove the max throttle screw but if you step on the accelerator pedal with your weight it might cause a little strain on the pump throttle assembly. Thus push the screw back in a little bit so that the lever will always hit the screw at max throttle.

Have someone step on your accelerator pedal again and see how far your throttle lever actually swings. Does it swing all the way to the screw like you did with your hand? Should your accelerator/throttle cable need tightening? Anyway, if your throttle lever has moved any further than before, you'll finally have a little more fuel now. Go for a drive.

Make sure you don't smoke too much.. no more than a light grey haze. If you're fueling a little too much, push the max. throttle screw in a little more. I did this on a 1.5 NA Rabbit recently and it went from virtually no smoke to quite the grey smoker (only at WOT).. it was also able to chirp tires in 1st gear when it couldn't before.

Many VW IDIs already have full throttle swing FYI.. but it's worth checking.

[zagarus]

well i adjusted the fuel a little tonight (not the max swing screw) but the more fuel screw, and well i can go up hills easier now     i didnt adjust it too much cause i dont want to damage the engine, but at least i know a little more of whats going on.  And i drove with no music tonight and damn, i love the sound of a turbo  :lol:

[turbotor]

The screw I was thinking about is right under this screw that is marked with red.

[RabbitJockey]

my car has a nice haze compared to the dark as night cloud it used to have.  i don't have any trouble chirping tires or going up hills.  i've actually chirped going into second gear before.  and i've had my tires spinning pretty good before too, like i could have kept them going.  but that was in the winter when it was running awesome.  the summer isn't as pleasing to drive.

[zagarus]

ya summer for me is gonna require an intercooler if i want to keep workin on the engine, winter was nice and all and especially nights, notice a big difference in performance, but summertime will be hot and cooling is a must.  So this summer plans will be to get an intercooler, and 2.5inch exhaust system from turbo back into a magnaflow muffler with a tdi style tip, and im gonna fibreglass the rear bumper to get a smooth clan look, then paint the car.  Gonna be sweet.  Hopefully get rid of the diesel sticking to the rear problem.

[addautomotive]

Does anyone use an electric lift pump to get more fuel at full throttle? I've always wondered if there are gains to be had there. I'd be curious to see what kind of vacuum the IP pulls at full throttle, and if you maintained a small pressure if you'd see any improvements.