Accelerator linkage

Duncan

Member
Has anybody found a fix for slack accelerator linkage?
2" free play - makes hill starts very difficult as pedal has to be pressed hard to prevent stalling
 
Has anybody found a fix for slack accelerator linkage?
2" free play - makes hill starts very difficult as pedal has to be pressed hard to prevent stalling

All A2 engines are "drive by wire". The accelerator pedal isn't connected to the engine, it just as a position sensor in the pivot. This tells the ECU how far its pressed and the computer decides what to do. In the case of a petrol, open the throttle butterfly valve, control injector timing and amount etc.

The 1.4 petrol is renowned for not having very much go at the low end with not much happening for the first part of pressing the pedal. It can be easy to stall when getting off and parking until you get used to it. I have a 1.4 petrol and even after 5 years I do still stall occasionally when parking. The problem is that there isn't much torque low down.

Your one does sound a bit excessive though. What's the clutch bite like? My clutch was burnt by a previous owner probably using excessive revs on manoeuvre to counter act the lack of low down torque. That meant that the clutch didn't really slip and so pulling away and hill starts were tricky. After about 5 years its almost back to "normal".

How's your engine running? A too lean mixture due to an intake air leak doesn't help low down torque and a dirty throttle body can block off the air supply at the bottom end. Are there any faults recorded on the engine?

Although a 1.4 petrol will never be like a diesel or large petrol engine for low down torque, I would never describe it as "undriveable".

regards

Andrew
 
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All A2 engines are "drive by wire". The accelerator pedal isn't connected to the engine, it just as a position sensor in the pivot. This tells the ECU how far its pressed and the computer decides what to do. In the case of a petrol, open the throttle butterfly valve, control injector timing and amount etc.

The 1.4 petrol is renowned for not having very much go at the low end with not much happening for the first part of pressing the pedal. It can be easy to stall when getting off and parking until you get used to it. I have a 1.4 petrol and even after 5 years I do still stall occasionally when parking. The problem is that there isn't much torque low down.

Your one does sound a bit excessive though. What's the clutch bite like? My clutch was burnt by a previous owner probably using excessive revs on manoeuvre to counter act the lack of low down torque. That meant that the clutch didn't really slip and so pulling away and hill starts were tricky. After about 5 years its almost back to "normal".

How's your engine running? A too lean mixture due to an intake air leak doesn't help low down torque and a dirty throttle body can block off the air supply at the bottom end. Are there any faults recorded on the engine?

Although a 1.4 petrol will never be like a diesel or large petrol engine for low down torque, I would never describe it as "undriveable".

regards

Andrew
Thanks for your comments
All A2 engines are "drive by wire". The accelerator pedal isn't connected to the engine, it just as a position sensor in the pivot. This tells the ECU how far its pressed and the computer decides what to do. In the case of a petrol, open the throttle butterfly valve, control injector timing and amount etc.

The 1.4 petrol is renowned for not having very much go at the low end with not much happening for the first part of pressing the pedal. It can be easy to stall when getting off and parking until you get used to it. I have a 1.4 petrol and even after 5 years I do still stall occasionally when parking. The problem is that there isn't much torque low down.

Your one does sound a bit excessive though. What's the clutch bite like? My clutch was burnt by a previous owner probably using excessive revs on manoeuvre to counter act the lack of low down torque. That meant that the clutch didn't really slip and so pulling away and hill starts were tricky. After about 5 years its almost back to "normal".

How's your engine running? A too lean mixture due to an intake air leak doesn't help low down torque and a dirty throttle body can block off the air supply at the bottom end. Are there any faults recorded on the engine?

Although a 1.4 petrol will never be like a diesel or large petrol engine for low down torque, I would never describe it as "undriveable".

regards

Andrew
Thanks for your comments
I agree as I previously had a 1.4 TDI
But there is no increase in revs during the first 2" of throttle movement and revs do not appear to die away during gear changes when pedal is completely released
Audi East Kent could not find any faults despite changing accelerator pedal
Problem is so bad my wife refuses to drive!
It means you have to stamp hard to raise revs when doing hill starts
 
The floor mat isn't stuck under it is it? I have not noticed this on our 1.4 petrol even after driving my 535d
 
The floor mat isn't stuck under it is it? I have not noticed this on our 1.4 petrol even after driving my 535d
Thanks for ideas
No its the 2" of free play before revs rise that make pulling away particularly on hill starts
As it is so unresponsive it either stalls or over revs to move off - very embarising
 
Sorry for hijacking the topic, but didn't wanna open a new one for my question. Can anyone confirm, that the gas pedal, 1.4 petrol, sits about over an inch lower than the clutch and break? Feels like I'm moving my legs a lot between gas and break, as I have to change the whole position to reach it properly and then back again. I was driving my old 1996 75hp 1.3 colt when I was visiting my family last week, and that thing feels twice as fast as the a2 even though they should be the same 0-60, but mostly my heels didn't need to move between gas and break, but I do that a lot in the a2. I'm thinking of aftermarket only has pedal tuning, to make it leveled with other pedals. Thanks
 
Sorry for hijacking the topic, but didn't wanna open a new one for my question. Can anyone confirm, that the gas pedal, 1.4 petrol, sits about over an inch lower than the clutch and break? Feels like I'm moving my legs a lot between gas and break, as I have to change the whole position to reach it properly and then back again. I was driving my old 1996 75hp 1.3 colt when I was visiting my family last week, and that thing feels twice as fast as the a2 even though they should be the same 0-60, but mostly my heels didn't need to move between gas and break, but I do that a lot in the a2. I'm thinking of aftermarket only has pedal tuning, to make it leveled with other pedals. Thanks
Just looked at the pedals on my FSI and the brake and clutch are perfectly level, yet the accelerator about 2" lower. Always thought the accelerator pedal was lower by design to reduce the risk of pressing both the accelerator and the brake at the same in panic braking, or indeed forcing the removal of the foot from the accelerator pedal to press the brake with almost a whole right leg movement.

Andy
 
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Just looked at the pedals on my FSI and the brake and clutch are perfectly level, yet the accelerator about 2" lower. Always thought the accelerator pedal was lower by design to reduce the risk of pressing both the accelerator and the brake at the same in panic braking, or indeed forcing the removal of the foot from the accelerator pedal to press the brake with almost a whole right leg movement.

Andy
Lots of car makers do this and probably its good for learners too, but I prefer the much closer levelled to the clutch and break. The sitting doesn't feel right like this, as I always have to stretch for the gas or being bit too close to the break.
Is there a way the pedal could be raised? I know it's not wired, but attached to some kind of sensor. Thanks
 
Just about every car I have owned has been laid out with the accelerator pedal lower than the clutch / brake pedals and at a different angle. I do not think - may be completely wrong here - that there is any MOT requirement as to their heights. I think it is there to help prevent braking and pressing the accelerator at the same time. The differences in the angles I put down to your foot is more accurate at the angle of the accelerator thus smoother operation is possible, it is more comfortable and lets face it your foot is on it far more than the others and stays on it. The brake and clutch pedals are only on / off pedals by comparison, but there angle allows the foot to apply a greater force which has to be a safety feature. Think of it more as squeezing the accelerator and stamping on the brake and clutch pedals. There may even be some "memory effect" in your foot that after braking the leg resumes the same position when you swap back to the accelerator. These are not based on any technical or legal documents they are only my explanation for the positioning of the pedals. If you notice the foot rest to the left of the clutch pecal on lots of cars is set about the same height and angle as the accelerator pedal so again guess it is for comfort and a more natural position for the foot.
 
I've been driving my A2 this afternoon and can confirm that the Tdi's pedals are as Andrew and Audifan describe theirs. I don't find them at all difficult to use but, if you want to see how a higher accelerator would feel, I suggest a three inch length of 2 X 1 timber, curved to suit the original pedal on the underside, drilled through a couple of times and cable tied to the standard accelerator, would give you the opportunity to try it.
 
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