2.0d starting problems, bad mileage, lack of power
 

Hi all,

I keep on having problems with my c30 2.0d. Mileage lately is horrible. On the highway doing 75mph, cruise control on, on flat roads I get an average of 35mpg, combined with city its even worse, 30mpg. I almost never go over 2000rpm, the dpf is not clogged, turbo pressure is OK, 4 brand new injectors.
I cleaned the throttle body and noticed that the valve which is shut by default does need a little pressure before moving (and clicks before it moves) is this normal or should it be smooth all the way from being shut to open?
on top of that I am also missing power. Friend has te same car, 40 to 60mph in +-3 seconds, mine in 5 seconds, same road, same conditions.
On top of that, my car doesn't start smooth when it is a bit colder. Starting from 0degrees and down the car sometimes needs 2 tries to start and when it starts it vibrates a lot for about 10 seconds and then it gets better, measured glow plugs, all 1.9ohm. DMF is on its way out though.
Anyone any ideas? Sorry for the long post, the car is driving me nuts lately..

Br,
Hans

Have you had the codes read on the car?
One thing you could try is swapping your friend's throttle body onto your car and see if that improves things.

No error codes on vida, forgot to mention that. 😊Next time I see him I will try that but that won't be soon. For now I'm stuck..

Update! Ran a couple of checks with vida and noticed I get around 230mg/stroke from the maf sensor when running idle while vida says it should be around 300. Also something very strange, when I turn the ignition on, the glow plugs come on, afters starting they go of, and then after a couple of seconds they come on again and stay on.. Did this happen to anyone before?

Hi,
I just did a test using vida. In neutral, I floor the accelerator pedal for one second and watch the desired boost pressure, intake manifold pressure, turbo control valve and air mass/stroke. I notice that the actual pressure only gets to 1500hpa while the desired is 2300hpa. Air mass per stroke on idle is also on the low side. And I also notice weird behavior on the turbo control valve when idling.. Does anyone have any ideas? Please help me out here, I'm getting more and more depressed everyday :-( rpm goes up to 4000rpm after 1 second btw. Thanks a lot for any help!!

Check the anti-shudder valve which is the throttle vane type thing which bolts to the inlet manifold - has it jammed shut?

The valve is vacuum operated and closes when you turn the ignition off so the engine stops dead and does not peter out over a few seconds as the fuel system pressure falls.

I've cut mine out and sealed the resulting hole with a nut & bolt & PTFE tape (also blanked the vacuum feed). The shudder on switch off is barely noticeable.

Do you mean the one of two valves in the throttle body which is closed by default? When connect a hose to it and suck it with my mouth it opens so if that's the one you mean it is not jammed, have to suck pretty hard though :-p thanks for your reply BTW!