Hello! Since I bought my fabia mk1 which was a few year ago there is a problem I still can't find out how to fix. I'm talking about 1.4 16v 101hp engine. The car is really sluggish up to 3000 rpm and when it goes after 3k it becomes really sensitive and pleasant to drive. While suddenly pushing the pedal at idling, the car needs like a second to respond. There is delay which makes it uncomfortable for driving at low speed. Also while taking off my foot from the accelerator pedal before shifting gears there isn't enough time for the revs to go down and it happens something like self-forcing. The revs comes down really slow. but there aren't any problems while idling. When I push and hold the accelerator pedal just a bit (let's say about 3%) and don't move my leg, there is hesitation in the revs (going up and down almost about 200 rpm). Checked that with vcds as well. There aren't any fault codes and what I've tried is switching the accelerator pedal (with the potentiometer) from another fabia which works well but that didn't make any change. I've cleaned the throttle body and the EGR and I've done

the adaptations needed after that with vcds. Also crank shaft sensor has been changed with a new one.  Would you suggest me what else to check ? Thanks in advence :)

I'd go right through the vacuum pipework and make sure there are no leaks and check the non return valve is working properly.

Coil packs?

EDIT: There is only one coil pack and I tried to change it.  The problem isn't coming from there. Thanks guys. Any other suggestions ? 

Can you possibly show a video of it happening?

 

Record it on your phone then compress the video so its below 10mb

I'm going to provide such a video a little bit later.

On the first video I'm pushing the pedal down and letting it go back almost immediately and you can see how the revs go down slower than I think it should be. In the second video I pushed the accelerator pedal slightly and held it there. The revs are really unstable and that's even more noticeable when I try to go forward at first gear and let out the clutch with almost no gas. I want you to  the car seems really stable while Idling and there isn't such rev hesitation.

Hi. I am having similar symptoms in mine '02 1.4mpi. When driving normally you have to change gears a little slowly for the revs to settle/go down which i think is bit odd. 

About the gas pedal response i remember reading somewhere here that Skoda made it sort of exponential so that you there is very little difference in how much pressing the first travel of the pedal does compared to the last. Presumably this was to reduce fuel consumption, but i really found it a bit difficult to get used to at first. Getting a smooth start up a hill in a hurry can be a bit tricky when its hard to control the revs precisely in my opinion. 

Did you find anything else about any of this?

Not sure if this applies but I'll mention it anyway.

 

Is there an upper clutch switch? When this failed on a previous car the revs would hang higher for a second or so.

Edited 31 October, 20223 yr by PetrolDave

11 minutes ago, FabiaIsLife said:

Hi. I am having similar symptoms in mine '02 1.4mpi. When driving normally you have to change gears a little slowly for the revs to settle/go down which i think is bit odd. 

 

I have the 1.4 mpi too and it seems be be a trait on them the revs drop fairly slowly when changing gear, etc.  Took some getting used to when I first got the car. Throttle response on mine is also the same as you describe.

The revs are falling off at the correct rate, yes an engine would slow down quicker on a closed throttle but at the cost of emissions (oil mist drawn through valve guides and past piston rings) so the idle by pass valve allows air but not fuel to pass removing the intake vacuum.

 

Fuelling is added as it nears idle speed and you can see that by the marked slowing down of the fall of the RPM, the hunting up and down between 800 and 1000 rpm is the idle stabilisation circuit, the first upwards blip I would expect but not the hunting while you were trying to maintain a fast idle, there will be an air leak somewhere, either a vacuum pipe, the idle by pass valve or EGR valve not seating properly.

 

I doubt that the revs will ever fall faster between gear changes than they currently do. The engine may also have a lot of inertia from the flywheel, if it has one of those abortion 3 bearing crankshafts then that alone will produce enough  inertia to make you change gear slowly.

9 hours ago, J.R. said:

if it has one of those abortion 3 bearing crankshafts then that alone will produce enough  inertia to make you change gear slowly.

 

 

It's a proper lump of pig iron.

 

Edited 31 October, 20223 yr by TMB

Yep, thats the one I was thinking of!

 

Add a flywheel to that and you would need to turn off the ignition 5 minutes before the engine would stop!