Throttle jumping to 1800RPM

[BlueFabDaz7]

Hi all

Only my third day in my new Fabia (SEL 110) and no doubt this is just a process of getting used to clutch and throttle (coming from a Yaris 1.4 D-4D).....but what I've noticed is that when pulling away from a standing start, the slightest touch on the throttle send the revs up to about 1800RPM. As the clutch is then being fed in, it drops to around 1000 / 1200 RPM and then drive off normally.

 

Is this little throttle 'blip' common? Didn't notice it on my test drive...but that was a couple of months ago so it may have and I've just forgot!

 

Thanks

Daz

Edited 13 January, 2017 by BlueFabDaz7

[ettlz]

Now that sounds eerily familiar... :notme:

 

It shouldn't instantly jump to 1800 rpm at a slight touch with no load on the engine. You should be able to get revs between that and idle. That said, I've found the throttle on mine requires a great deal more ankle precision than it did on the Citigo. It doesn't help that the throttle return spring is so light, giving next to no feeling -- that part of my brain responsible for translating desired power to food movement has to try very hard. Sometimes I find rolling my foot side-to-side gives better control.

 

Does yours have a small unresponsive spot at the start of the pedal travel too? It's a shame there's no screws on it to adjust that out.

 

The clutch has a very different curve to the Citigo as well, the engagement part is steeper. Then again, the Citigo is a ridiculously easy car to drive. (The trouble with comparing to test drive vehicles is you don't really know how sympathetically they've been treated. Also on the test drive you'd be more "aware" that it was a different car, with other aspects of the drive occupying you more at the time.)

Edited 13 January, 2017 by ettlz

[fzrkev]

Mine does this too. 1.2tsi 90. Asked the dealer about it and all normal. Even the courtesy car did it. You can raise the revs slowly bit it requires mm perfect control. If you let the clutch out slightly before throttling, you'll notice the revs increase to 1k automatically. It's smoother doing it that way I've found.

[GeneralPurpose]

Blue, it's normal for all the TSI engines on these Mk3's. They are sensitive (it's fly by wire) but once you get used to it you won't have a problem and you won't even think about it. Remember, these engines produce maximum torque at 1400rpm and what with the fly by wire slightly sensitive system, it does take some practice to start with. Best way to get used to it is to set the throttle so that the engine revs are at 1200rpm. Next raise the clutch slowly to the biting point and hold it steady as the car starts to move forward. Feed in more throttle as you need it. It's like going back to basics when we all learned to drive. You'll be fine.

Edited 13 January, 2017 by Estate Man

[ettlz]

Blue, it's normal for all the TSI engines on these Mk3's. They are sensitive (it's fly by wire) but once you get used to it you won't have a problem and you won't even think about it. Remember, these engines produce maximum torque at 1400rpm and what with the fly by wire slightly sensitive system, it does take some practice to start with. Best way to get used to it is to set the throttle so that the engine revs are at 1200rpm. Next raise the clutch slowly to the biting point and hold it steady as the car starts to move forward. Feed in more throttle as you need it. It's like going back to basics when we all learned to drive. You'll be fine.

 

Presumably somewhere in VAG engineering a decision was taken to make the throttle response this sensitive. Which seems odd because the one of the points of an xBW system is to reduce human manual control effort so the operator can dedicate more time to situation awareness. (Although to be fair TSI would probably be hard to do without at least some software intervention.)

 

Trying to hold 1200 and release the clutch can be easier said than done with a sensitive throttle. As the left foot comes up the body twists sufficiently to alter the throttle position. I also have the suspicion that the EMS can take matters into its own hands -- throttle control is also a function of clutch position, as noticed by fzrkev. I'm not convinced this is anti-stall, it happens well before the biting point. Unfortunately none of this is documented one way or the other.

 

Other than that, the engine's a hoot -- and quite a riot for a 1.2.

Edited 13 January, 2017 by ettlz

[fzrkev]

There also seems to be 2 maps in use. Map 1 is when stationary and has a rev limit of 4k. The response after the initial jump to 1200rpm is fluffy. Not alot of revs compared to pedal travel. Map 2 kicks in when you've reached a certain speed. You can feel it change if you give it some off the line and polish the clutch a bit. Kinda works in reverse to the way you think it should. I.E. Big throttle movement to get going then lift off a bit when the clutch is engaged. I feel this doing hill starts. It's fine pulling away, but then accelerate too quickly and have to back off. I'm sure it made sense in the strokey beard meeting at VAG HQ when this was invented.

[GeneralPurpose]

fzrkev, if that's your actual photo in your post, aren't you a bit young to be driving...lol! Agree with ettiz, these TSI engines are a real hoot to drive...loads of fun! These TSI motors have variable valve timing and it's that, along with mapping changes that you can feel taking place. Nice extra surge of power. 

[BlueFabDaz7]

Thanks all

Had a good drive out this weekend trying to get used to things. As mentioned, feeding the clutch in slightly first along with the throttle keeps it nice and smooth. Even without that, have got my right foot movement a little finer now so that even if it does jump, it only jumps to about 1500RPM.

 

Just a case of re-mapping my brain / foot combinations coming from a Yaris diesel.

 

Cheers

Daz