Before I beat a path to my dealer, can anyone else with cruise fitted to a vRS TDI tell me if they suffer these symptoms?

Downhill with zero throttle (MFD showing "----- mpg") instead of gliding gently and smoothly downhill, the crusie can't make up its mind whether to keep the throttle on or off. The result - kangarooing between power on, power off, power on, power off etc etc - you get the picture. Is it a faulty cruise, or will the dealer tell me "they all do that sir"..?

Mine does not act in that way at all, its very smooth downhill at around 40mph and showing ----mpg on the maxi. hope this helps

That's not normal

Depends on what gear you are in surely? If you are in a gear where the revs are below a 'normal' running point you may suffer these symptoms!

Yes, but thats not a problem with the cruise thats the way you drive.

I believe it is normal depending what your speed is as cc tries to maintain speed using the engine.

If your car won't maintain say 70mph downhill with no throttle then it will accelerate slightly back to 70 then ease off so it doesn't overspeed. Try going down hill and maintain your speed at a constant using the throttle only and you'll more than likely find you are on and off the throttle too. The effect will probably be less at lower speeds. At motorway speeds I tend to disconnect it down hill to avoid the effect.

(I stand to be corrected but this is my understanding of it) Hope that makes sense.

Jacko

I've not had it unless I've had a dying DMF and then it went as soon as that was replaced.

Personally I'd say it's not normal although an occasional plip on the throttle from the CC if the car is slowing a lot it'sn abnormal you shouldn't really feel it like that.

Downhill with zero throttle (MFD showing "----- mpg") instead of gliding gently and smoothly downhill, the crusie can't make up its mind whether to keep the throttle on or off. The result - kangarooing between power on, power off, power on, power off etc etc

My 2.5 TDI Transporter very occassionally does this, but it only seems to be on certain downhill gradients of a particular steepness (for me it is when the MFD is showing about 1.5-1.8 l/100Km). It is quite noticeable, as the rest of the time it is exceptionally smooth and subtle (best cruise control I've ever had). It is almost like the progarmming map can't cope with that particular circumstance. I often drive the same route, and it only does it on certain hills, and then only about 1 time in 5 or 10, so not very often at all. Possibly it is only a particular speed and gradient ? I'll have to try setting the CC for a slightly faster or slower road speed next time it happens to see what affect that has.

If yours is doing it consistently then it is almost certainly faulty. It is quite irritating when it does happen, feels like it is being driven by a very clumsy driver.

My 2.0TDI has a very smooth cruise, not noticed any problems as long as i don't try 35mph in 6th!

Hi rsbspt.

I have cruise fitted to my vRS Tdi.

Done 25k and I use the cruise quite a lot. Never had any problems what so ever.

When going downhill and the set speed is exceed, the cruise does nothing until the vehicle reaches the bottom of the hill and naturally starts to slow. As the set speed is approached, the cruise kicks back in and away you go once more.

I think it is worth checking out with the dealer and no, 'they all don't do that'.

Good luck.

Before I beat a path to my dealer, can anyone else with cruise fitted to a vRS TDI tell me if they suffer these symptoms?

Downhill with zero throttle (MFD showing "----- mpg") instead of gliding gently and smoothly downhill, the crusie can't make up its mind whether to keep the throttle on or off. The result - kangarooing between power on, power off, power on, power off etc etc - you get the picture. Is it a faulty cruise, or will the dealer tell me "they all do that sir"..?

Is the engine remapped??

My cruise control is very smooth. In fact its the best CC Ive had on any car to date. Yours is definitely not working properly IMHO.

At certain speeds going downhill it occasionally will get in a position where it does go on and off the throttle as you describe , but it's not common and just going one or two mph faster or slower will stop it

Is the engine remapped??

Nope, standard. But I must say I'm tempted, as the 170 engine seems to have a big flat spot which a re-map might eliminate...

Just be a bit careful with the map as if you put too much torque low down on any modern derv with a DMF you will damage it.

Just be a bit careful with the map as if you put too much torque low down on any modern derv with a DMF you will damage it.

Fair point - but I'm not actually looking for any more power or torque, just the elimination of that darned flat spot...

Fair point - but I'm not actually looking for any more power or torque, just the elimination of that darned flat spot...

I know what you mean, but as an example the ford focus 1.8TDCI had a flat spot put in on purpose to protect the DMF. That was at low revs hence it was so easy to stall.

I know what you mean, but as an example the ford focus 1.8TDCI had a flat spot put in on purpose to protect the DMF. That was at low revs hence it was so easy to stall.

The plot thickens. That's exactly when the flat spot shows up on the Octy and yes, I do occaisonally stall it...something I never did with the Furby. Another reason I should have gone for petrol...

The plot thickens. That's exactly when the flat spot shows up on the Octy and yes, I do occaisonally stall it...something I never did with the Furby. Another reason I should have gone for petrol...

If you find it seriously easy to stall and a bit almost jumpy when pulling away it might be worth popping the car into the dealer and asking them to check the DMF as they have been known to break occasionally