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[diyjoe]

Time marches on and I am desperate to keep on driving my omega, I have for medical reasons had the car fitted with mechanical hand controls.  The accelerator pedal has been converted to flip up when I drive and down again for normal use. Trouble is the hand control is fitted close to the pedal pivot pin and needs a lot of pressure to get going smoothly. I have thought of installing a lighter return spring which would help me but not sure what effect it would have on the car or on other drivers.

Not that I know where the return spring is as yet and I can't afford electronic contraptions. Any suggestions at all would be appreciated except give up driving

[Nick W]

Has it always been like this, or become stiff?
If it needs a lot of pressure to get moving perhaps the leverage is inadequate which will have been permanent, or the linkage is binding and needs adjustment - most of the hand throttles I've seen have been quite complicated.

Any modifications must be fail-safe: the linkage must return to a closed throttle when released.

[Kevin Wood]

Assuming it's the 2.6 that's listed in your profile, this has an electronic throttle, so the pedal just moves a pot which sends an electronic throttle signal to the ECU. I haven't looked but the return spring is probably just mounted on the pedal itself and might well be quite easy to change.

Drivers using the normal controls would have to take a bit of care, as it would become more sensitive.

I wonder if cruise control would help? That's quite easy to retro-fit if you don't already have it and it would remove the need to keep constant pressure on the hand controls while running at a steady speed.

[Diamond Black Geezer]

Indeed, and also are incredibly 'slack'/weak...you need to have a go driving my V6, which is a 'proper' cable throttle, and is at least twice as hard to push compared with my old DBW Diesel... as above, a different spring would theoretically help.

[Kevin Wood]

In theory, you could even have a completely separate throttle pot mounted on the steering column, much closer to the hand controls, and a switch to select input either from it or the normal pedal, and then you could get rid of most of the troublesome mechanism down to the pedal itself.

However, I'm not sure:

a) If there's any "learning" of the sensor characteristics in the ECU which would be confused by switching sensors.
b) If you'd get told to get lost by your insurer having declared such a mod.

 

[Nick W]

In theory, you could even have a completely separate throttle pot mounted on the steering column, much closer to the hand controls, and a switch to select input either from it or the normal pedal, and then you could get rid of most of the troublesome mechanism down to the pedal itself.

However, I'm not sure:

a) If there's any "learning" of the sensor characteristics in the ECU which would be confused by switching sensors.
b) If you'd get told to get lost by your insurer having declared such a mod.

 

That would make sense to me, but considering the blacksmith engineering of the hand controls(and dual controls) I've seen I doubt that many of the suppliers are capable of doing it. I couldn't do it, but would happily make the mechanical parts.

[Kevin Wood]

That would make sense to me, but considering the blacksmith engineering of the hand controls(and dual controls) I've seen I doubt that many of the suppliers are capable of doing it. I couldn't do it, but would happily make the mechanical parts.

Yes, it's quite surprising that the manufacturers of hand controls haven't spotted this opportunity now that the majority of cars are DBW. Like you say, though, they take a "Blacksmith" approach.

[zirk]

Not sure if this is going to help, but I will be in the process of removing a Disabled Controls from an Omega 3.2 Auto, its a combined Brake and Accelerator Hand Control, right hand side of the Steering Wheel, I have driven it, from memory the hand control is push forward to brake, push towards you to accelerate (or was it the other way around). it certainly wasn't hard or dificult to operate, its been professionally fitted, the 2 foot pedals are still intact, so it can be driven from the foot pedals or solely on the Hand Lever.

I will probably buy the car from Him and part of the deal was I remove disabled part for him, as it wasn't cheap, with the view to possible fit, or He can get it fitted to his new car, But I not convinced it will bolt straight on to something new as it was designed for the Omega.

If you want I can make some inquiries, should the unit become redundant.

[diyjoe]

Thank you all for the replies and suggestions.
The car drives perfectly when driven with the foot pedal, and is no problem to drive at steady speed or changing speed with hand control, its just the initial pull upwards of the hand control to get the car rolling smoothly without lurching forward that is the problem. The specialist fitters have checked the system and can find nothing wrong with the hand control. They have agreed that the pressure on the pedal arm is greater by hand than the pressure applied by foot if the linkage by hand was direct to the pedal arm, but the design of the hand control compensates for this. They have politely suggested it could be the lack of strength or control of my hand that is the problem. However I did take a physical and driving assessment in a small car with hand controls before I had my hand controls fitted and had no trouble at all. I think I will have to use the services of a garage to check the car out.

Eric

[Doctor Gollum]

Replacing the pedal linkage with a more suitable routed and connected cable might do it... I presume that the hand lever and pedal are physically connected so that the car thinks all is normal might also be that the return mechanism on the hand control is heavier in order to counter the brake pedal return spring causing far greater effort to be required.

Sounds primarily like a geometry issue on the accelerator pedal though and Kevins suggestion of fitting cruise control is a good one... even if used in an urban environment,  as soon as you move to brake, it switches off. For most people using it in such a way would be a bind, but it might make your driving a bit easier