I've just got round on putting the vegiboost stuff in the car (40ml over full tank of diesel) today and it went into limp mode straight after I started up.

I've checked all the boost pipes etc they are fine. I tried to switch off ignition and on again but it wouldn't go away. Now currently have battery unplug to see if I can reset the limp mode.

Annoyingly I misplaced my obd cable to check exactly whats wrong. Are there any common problems which will kick it in limp mode instantly as the car is started?

Sharks little box of tricks doesnt seem to detect any DTC codes either. Maybe I should reflash the ECU again to reset it?

Any thoughts/help would be great. Thanks in advance.

I wanted to try this stuff. I thought it was 10ml to a tank though?

Can't help with the limp mode though, sorry :(

Ah, on the description it says 0.1% of the total volume. 0.1% of a 40litre is 40ml isnt it?

Ah, on the description it says 0.1% of the total volume. 0.1% of a 40litre is 40ml isnt it?

Oh right, if that's the case then yeah... that'd work out as 40ml I think. I'm sure I read 10ml somewhere Maybe it's Millers that has 10ml per "dose" and I am getting confused.

Got any further, or still leaving with the battery off for now?

Ah, on the description it says 0.1% of the total volume. 0.1% of a 40litre is 40ml isnt it?

I'm not the sharpest knife in the drawer, but 0.1% equates to 1ml per 10 litres.

So 4ml equates to 40 litres.

1% per 40 litres equates to 40ml

Go on say I'm no good at maths. LOL

Goggled the sum and I got above answer so wrong Dad.

As below 'vrs180' states.LOL

I'm not the sharpest knife in the drawer, but 0.1% equates to 1ml per 10 litres.

So 4ml equates to 40 litres.

1% per 40 litres equates to 40ml

Go on say I'm no good at maths. LOL

Your no good at maths........

0.1% of 40 liters = 40 millilitres.

eg: 40,000 (millilitres) divided by 100 = 400

400 x 0.1 = 40 (millilitres).

HTH

Bill.

Update.. still on limp mode, but when full load and change gear I hear turbo chattering. Does this mean something bad? :(

Update pt 2.

1 Fault Found:

17957 - Boost Pressure Regulation Valve (N75): Open or Short to Ground

P1549 - 35-10 - - - Intermittent

Readiness: N/A

trying to find the next step.. feel free to shout something to test/try if its a common fault.!

Sent from my Desire HD using Tapatalk

N75 is in the vacuum box on the drivers side inner wing. It controls the Turbo Vacuum Actuator for the variable vanes (VNT)

1: Check the N75 port is providing vacuum to the Turbo Actuator

2: Check Turbo Actuator is free to move and not stiff (Stuck VNT)

3: Using a vacuum pump, apply vacuum to turbo actuator and make sure the rod to VNT moves (if not actuator diaphragm shot.)

Engine OFF for steps 2 and 3

N75 is in the vacuum box on the drivers side inner wing. It controls the Turbo Vacuum Actuator for the variable vanes (VNT)

1: Check the N75 port is providing vacuum to the Turbo Actuator

2: Check Turbo Actuator is free to move and not stiff (Stuck VNT)

3: Using a vacuum pump, apply vacuum to turbo actuator and make sure the rod to VNT moves (if not actuator diaphragm shot.)

Engine OFF for steps 2 and 3

Thanks! I was trawling around the net trying to find where it is in the car, I'll have a go at sorting it out tomorrow. I assume the N75 rarely give up? I see a fair few threads talking about J valves and race valves etc. Suppose its a maintenance upgrade if the valve is shot .

Thanks! I was trawling around the net trying to find where it is in the car, I'll have a go at sorting it out tomorrow. I assume the N75 rarely give up? I see a fair few threads talking about J valves and race valves etc. Suppose its a maintenance upgrade if the valve is shot .

N75 is pretty reliable, but the black vacuum box it's in does pack up sometimes (the black box also operates EGR and intake air temperature flap)

The turbo actuator bolted to the turbo does sometimes fail (diaphragm leaks). Skoda will not supply just the actuator, but state that you need a new turbo. This is rubbish, as you can get a new actuator from most good turbo places, or even from a scrapper.

Don't rule out vacuum hoses between N75 and Turbo, they can crack and leak.

N75 is pretty reliable, but the black vacuum box it's in does pack up sometimes (the black box also operates EGR and intake air temperature flap)

The turbo actuator bolted to the turbo does sometimes fail (diaphragm leaks). Skoda will not supply just the actuator, but state that you need a new turbo. This is rubbish, as you can get a new actuator from most good turbo places, or even from a scrapper.

Don't rule out vacuum hoses between N75 and Turbo, they can crack and leak.

Right, the actuator moves up and down, it get progressively tighter the more you push it down, doesn't feel sticky so I assume the vnt is fine?

I took the vacuum box out but im pretty sure you cant take it apart? Or is it simply brute force by prying the top open?

Silly question but how do i test the vacuum on the n75 valve? ignition pos 2 and stick my finger on the port to see if there is vacuum?

Also... is this supposed to sound normal..? It does this when I switch from ignition 2 then off (I done it twice in the vid).

http://www.youtube.com/watch?v=eITHRKqbzLQ&feature=player_profilepage

Sorry I also didnt note that, I could not clear the fault code as stated above. It just came back near instantly. So could this be a electrical fault in terms of ECU detecting there is a clear break in the circuit thus near instant flagging up..?

The black vacuum box is non serviceable, sealed unit. If the code is coming back without starting the engine, good bet it's the vacuum control box that's faulty. The video sound suggests that something is trying to cycle itself, and it shouldn't happen. I would remove the boost pipe to EGR and check that the butterfly is open, and the EGR plunger closed.

The black vacuum box is non serviceable, sealed unit. If the code is coming back without starting the engine, good bet it's the vacuum control box that's faulty. The video sound suggests that something is trying to cycle itself, and it shouldn't happen. I would remove the boost pipe to EGR and check that the butterfly is open, and the EGR plunger closed.

lol I really dont know whats wrong.. I blocked up the EGR pipe and this time the code cleared, went for a test run (50mins), it started off sounding like a rich fuel mixture but after the drive it was sounding like it should, felt smoother aswell (must be from the egr block and higher centene levels). What is strange though no CEL light is up yet, maybe it'll come on tomorrow. The car is toying with me..

Thanks for your help dude, I'll keep an eye out for it and keep the other eye out for a replacement vacuum unit.