[Stoep]

Hi all,

Here in the Netherlands, MOT (APK) smoke tests are done with a stationary vehicle. Now, I am toying with the idea to use the speedpulse to find out wether or not the car is moving and with this signal drive a valve to allow or disallow the boost pressure to reach the fuel pump (on boost compensator).

When stationary, less fuel would reach the engine, allowing for more tolerance in the internel max-fuel setting.... Maybe a suitable valve would be my EGR control valve. Since I disconnected that one, I can use it for this purpose. (dunno if it would withstand 18 PSI - anyone?).

I know for a fact that newer diesels use the engine load and road speed (amongst others) to control (limit) the amount of fuel going into the engine (especially when stationary), so why not on a Mk2

An extra dash-switch could be added too, to switch between "economy" and "sport" (it wouldn't be either really tho, LOL).

Reactions please!

David

 

[totalguy]

why not get an adjustable boost controler you can get electronic ones and you can flick a switch in the car to adjust it. not sure where you would get one but ive definately seen them.

 

[Stoep]

Hi m8,

Thanks for the reply! :thumbup:

Your idea would lower boost pressure ie the amount of air, lowering the air to fuel ratio (AFR), increasing smoke levels.

My idea limits the amount of fuel going into the engine, increasing the AFR thus giving a cleaner burn (less smoke).

With this increased AFR, the max fuel setting could be turned up a bit more... without failing MOTs smoke test.

David

 

[reaper]

although i have nothing to offer this does sound very interesting

 

[derv]

umm.....how about pulling off the pipe on the boost compensator for MOT time? Would mean no boost getting to pump thus no extra fuel added.

That may be a useless suggestion but I'm a little confused, lol.

 

[totalguy]

thats a good idea derv easily done too unclip the rubber piece of pipe the pump end

 

[Stoep]

umm.....how about pulling off the pipe on the boost compensator for MOT time? Would mean no boost getting to pump thus no extra fuel added.

That may be a useless suggestion but I'm a little confused, lol.

That was what I had in mind, but then not a manual disconnect... but electronically controlled.

"Disconnect at 0MPH" - automatically...

Wouldn't have to think about it and since it would be a fixed install the garage would not see a disconnected thing and reconnect it for me (just like they always refit the shock absorber on the fuel pump, free of charge...).

Cheers for the feedback

David

 

[totalguy]

thats easy like i said before get a motorised boost controler which u can shut it off totally if you want via a switch or knob inside the car, you tee into the boost pipe when you fit a boost controler so if you got a motorised one you can do anything with it really.

 

[derv]

Fold the pipe over and wrap a cable tie over it to shut it off. Done somehwere out of sight, could work if it's only for a one time only attempt.

Even easier just screw the boost compensator screw right in as far as it would go!

 

[derv]

Tee in

Surely that would mean there's still boost getting to the compensator if it's only a tee piece? Or do you mean tee into the actual boost pipe from the actuator?

 

[totalguy]

oh yeah i got something wrong here i was thinking of boost guague on the boost pipe crossed between the boost controler oops :}

anyway to correct myself, a boost controler coulsd stop boost although it probably wont fully stop it best thing to do is doscinnect the boost pipe or put a valve on the pipe to put it on and off.