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MG MGF Technical - jerky accelerator

Hellooo!

I have a prob with my F. It is a preg vvc. (Thats not the problem!)

When I press the accelerator it feels like the cable is rubbing on metal (ie it is hard to push down in a 'jarry' way and feels like it needs lubricating or something. In the winter it froze solid so this may be connected.

Also when i apply the brakes on the M25 it tends to veer to the right a bit.

Thanks v v much for any help

abb
Abb

It is a preg vvc.
Whens it due?

>When I press the accelerator it feels like the cable is
>rubbing on metal (ie it is hard to push down in a #
>'jarry' way and feels like it needs lubricating or
>something. In the winter it froze solid so this may be
>connected.

First thing to do is open the boot and check if the throttle linkage is smooth,

if it then check the cable is on the cam, they can come off and give this (not very lightly, but free so worth checking)

If that is not the case then it probebly has had water get into the cable and it has corroded (fits freezing up problem). If this has happened you could try to revive it by squirting oil into the wire jacket, but in order to do this you will need a special tool (a motorbike shop might do it for little £) But you will probebly have to change the cable itself.
Will Munns

Thankyou Will

it has had its 5 year service 8 mths ago.

Im a bit crappy with mechanics...what does this mean and how do i do it?

(check if the throttle linkage is smooth

if it then check the cable is on the cam)

thanks
Abb
abbey

>>check if the throttle linkage is smooth
get someone to push the acelerator whilst you look into the engine bay, the bits you see move are the linkage, the cable runs around a plastic wheel, this is the 'cam' (In this case, not to be confused with the other cams in the engine).
Remove person from the car and try to move the linkage by hand (rotate the cam), it should be smooth.


>>if it then check the cable is on the cam)
when you rotate the cam by hand you should see the cable lifting up from between two ridges on the cam, if it is not within these ridges then make it so.

If the cam does not move freely then it could be destroyed roller bearings, in which case a replacement throttle body is in order, a trophy one will slot right in and give you more power (~£100)
Will Munns

Open the boot lid and remove the grille to the engine bay (it just clips into position, 4 wire legs and 4 wire clips).

As you look at the engine to your right is a black alloy rectangle with the letters VVC cast into it, this is the inlet plenum, attached to the left of this is the throttle body - this is the bit we are interested in.

On the front of the throttle body is a semi-circular wheel connected to a cable, this is the throttle cable (the other end of it is attached to the accelerator pedal). Have a look at the semi-circular wheel, the cable attaches at one end and runs around the wheel in a groove, basically when you press the accelerator, the cable pulls the wheel round.

Check 1) Inspect the wheel and make sure the cable is sitting in the groove. If not, rotate the wheel manually to give you some slack and place the cable back into the groove. This should cure the problem.

Check 2) Grab the wheel and rotate it manually, the action should be smooth with no jerks. If there is any resistance (other than the spring) you should be able to feel if it is the wheel or the cable that is causing the problem.

If it is the cable, my advice would be to have it changed - if it is kinked / rusted internally then it could snap and this will leave you stranded with a pedal that is not connected to the engine.

If it is anything else, then post back here and we'll see what else we can come up with.

Good luck

SF
Scarlet Fever

Beat me to it Will :-)

SF
Scarlet Fever

Yeah, what Andy says, english mode not enabled today ;-)
Will Munns

Abb

If all the above point to needing a new cable then it is at least worth lubing the one already fitted.

Go to BikeStop in Stevenage Old Town and tell John you need a cable oiler and a can of GT85 silicone spray.

Follow instructions on the card that the oiler is attached to - basically fit the oiler round the cable and squirt lube into the oiler.
John Ponting

>>Also when i apply the brakes on the M25 it tends to veer to the right a bit.<<

Abb, have you checked the condition of the tyre treads, and the pressures recently? Usually, the car pulling to one side indicates that the tracking is off. Feltham tyres near Heathrow will do a four wheel alignment for 40 quid - excellent value, and good work.

Hopefully you'll get the car sorted soon! :o)
Rob Bell

Abb, as you're in Herts you wouldn't be a million miles away for a trip to the next Essex Roadsters meet. You could always come along and have a handfull of guys (me included) have a look and see what we reckon? Just an idea.....

Ian
Ian

Sorry Ian but Herts really is a million miles away from Essex!
John Ponting

Haha, ok John good point to which I concede, but, I did mean geographically!

Ian
Ian

This thread was discussed on 30/07/2003

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