Increasing fuel on the pump

E_T_V
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Re: Increasing fuel on the pump

Post by E_T_V »

It shouldn't make much difference and depending on how it was originally tuned you may see a small improvement in economy, however if you don't drive it any harder then the economy change will be minimal.
Remi55
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Re: Increasing fuel on the pump

Post by Remi55 »

This sound great ;) Well I'm rather an economic driver, changing gears before 2.500rpm and driving always in the highest gear :lol: sometimes if it's needed i unleash the power of my SD :D
Remi55
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Re: Increasing fuel on the pump

Post by Remi55 »

Well I'm back with some info after my tuning steps :lol:

I fitted an cone air filter:
http://www.youtube.com/watch?v=gvXahamyOas

Makes a lot of noise and after a 2h drive on the motorway i had enough of it :lol: I have to built an airbox :D

Next i shorten the linkage on the acurator but my gauge showed only once 1.2bar and after that it never gets above 1.1bar. I think the boost-hose on the gauge slipped off because i can hear a whislting noise above 0.5bar ;) I have to check this. :roll:

But my biggest problem ist a "bending metal under high pressure" noise. It sound like a bending submarine outer hull at great depth :shock: I comes from the pump after turning the max fuel screw.

Image
I started like this upper pictures shows ;)
My staring point was a mark on Pos.0, then i turn the screw clockwise in such way,that after locking it with the locknut it stopped on pos.1 :) But on Pos.1 no i couldnt feel any improvment, the idle speed was still the same as from the beginning, no smoke cloud and after each motor starting I got this bending noise :shock: I had gone away after 2-5sek after the engine was running :geek:

Then I though maybe I have overtighten the locknut so I unscrew it again & turn the max fuel screw to pos.2. The locknut now is not so strong tigthten up. I can feel a improvment, the idle speed is a little bit higher but the bending sound is still available. It's no longer so oud and noisy but i can still hear it after the engine start & the difference is that it not allways appears. :|

Maybe you have an explanation for thsi bending sound :?: ;)
E_T_V
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Posts: 439
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Re: Increasing fuel on the pump

Post by E_T_V »

Remi55 wrote:But my biggest problem ist a "bending metal under high pressure" noise. It sound like a bending submarine outer hull at great depth :shock: I comes from the pump after turning the max fuel screw.

Image
I started like this upper pictures shows ;)
My staring point was a mark on Pos.0, then i turn the screw clockwise in such way,that after locking it with the locknut it stopped on pos.1 :) But on Pos.1 no i couldnt feel any improvment, the idle speed was still the same as from the beginning, no smoke cloud and after each motor starting I got this bending noise :shock: I had gone away after 2-5sek after the engine was running :geek:

Then I though maybe I have overtighten the locknut so I unscrew it again & turn the max fuel screw to pos.2. The locknut now is not so strong tigthten up. I can feel a improvment, the idle speed is a little bit higher but the bending sound is still available. It's no longer so oud and noisy but i can still hear it after the engine start & the difference is that it not allways appears. :|

Maybe you have an explanation for thsi bending sound :?: ;)
I'm not sure of the type of noise you are hearing. Perhaps you could video/record it? Turning the max fuel screw should have no affect on the engine noise aside from increasing the idle speed until you reset it back to normal.

Are you sure your new air filter isn't rubbing on something or something similar? As it us unusual for the pump to make any real noise aside from the buzzing when the engine isn't running.
Remi55
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Posts: 33
Joined: Thu Oct 01, 2009 10:44 pm

Re: Increasing fuel on the pump

Post by Remi55 »

I tried to record it, but the weather the past few days was very very windy in Vienna and you couldn't really hear the noise.

Yeah it's definitely coming form the pump because when you put your head next to it, it's the loudnest generation point. Holding the cone filtr doesn't make any difference and isn't rubbing against anything. This was also my first thought.

If you start the engine about 1 or 2min later after you turned it off the sound isn' available, you have to wait min 5min or longer to hear it. As i wrote in the other posting it's now after the 2."fuel increasing" attempt not always hearable at the engine starting point but sometimes at the turning off point.

The noise is a little bit similar to a not bleeded servomechanism :shock: It's making the same bending noise ;)

I also discoverd if you start you car without any gear (neutral position) the noise never appears, but with first gear in and pushed clutch it's hearable. While you driving there is silence :| :geek:
E_T_V
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Re: Increasing fuel on the pump

Post by E_T_V »

Does the noise come and go if you press and release the clutch pedal in neutral? If so then i'd suspect a worn clutch release bearing which is near the pump inside the bell housing.

Otherwise aside from a worn engine mount or something rubbing on the clutch arm I'm a bit puzzled as to what it could be.

Altering the max fuel screw simply moves a coller inside the fuel pump which controls where the fuel pressure is released as fuel is delivered to the injectors, so I can't think of why you are getting this flexing noise.

See if you can get a recording of the noise and see if you can isolate any of the components that are causing it.
Disgusted
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Re: Increasing fuel on the pump

Post by Disgusted »

I agree, it sounds like clutch release bearing, or gearbox input shaft bearings.
Remi55
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Re: Increasing fuel on the pump

Post by Remi55 »

Maybe it's really the clutch (is't still the first one in and I've got 200.000km on the clock :D ) but why ist now less noisy after i changed the "fuel screw position" :o That's the big mystery for me. In position one it was more noisy and i tested it two times before i changed the position 2. Now is quieter ;)

On the day before i started to tune the pump everthying was fine. I was twice in a supermarket that day and couldn't hear any suspicious sound. Then after the tuning steps I took my girlfreind for a test drive to the same supermarekt, some time later we get back in the car, started the engine as always and the sound was very clear hearable. My girlfriend was a litlle bit shocked. :o :D

I'll try tomorrow to record the sound and how i turn the screw. I'll also screw the bolt back to the original position and see if it this noise still appears. So long thank you for the help ;)
Remi55
Bolt Twiddler
Posts: 33
Joined: Thu Oct 01, 2009 10:44 pm

Re: Increasing fuel on the pump

Post by Remi55 »

Ok, i ha no success to record it :( It's gone and I tried one hour with 5min wait intervals :?

Here is one Video:
http://www.youtube.com/watch?v=zr67QC7VQm0

It's running perfect now and also the boost increases up to 1.25bar :D I have done nothing to be honest. That's a real mysterie :evil:
Remi55
Bolt Twiddler
Posts: 33
Joined: Thu Oct 01, 2009 10:44 pm

Re: Increasing fuel on the pump

Post by Remi55 »

Hi,
I'm back with some good news. I found out what cause the bending sound :lol: It was the cooling fan :shock: The bottom Intercooler pipe squeezed the plastic cooling fan casing and as a result the fan baldes couldn't rotate. :(

I also have some pics for you of the smoke screw. :lol:

Image

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