MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGF Technical - sticky throttle

Okay

were do I start well I have ha dmy MGF for the last 12 months and have spent a stupid amount of money on it not on anything special either just things like a clutch brakes but now I have reached the end of my rope with a sticking throttle, I have changed the Throttle body no change so Im appealing to you fellow owns for HELP does any one have an answer for me please HELP.

If only to eliminate the things that I have already done.
Mike

Is the throttle cable sticking in the sleeve. They can get dirty and snag, I had a similar problem and a spray of WD40 did the trick.

Also stepper motor could need resetting, turn on ignition and push accelerator 5 times. Turn off ignition and then start engine.

Do you feel any tension on the pedal or is the engine just revving high when you release.
Chris Catchpole

Good advice from Chris there :o)

Echoing Chris's question, could the symptoms be described as an occasional high idle? If so an intermittent sensor failure might be the cause - loads of stuff in the archives, well worth a look.

A sketchy connection somewhere can produce similar symptoms too, well worth unplugging every electrical connector you can find and sluicing both ends with electrical contact spray (Maplins etc), including the ones you unplugged to swap the throttle body as they still can't be ruled out.
Mike Hankin

Now you have changed the TB have you checked the cable returns fully. Get a freind to help. Might just be catching somewere. Jamie
j.peirson

Thanks folks for the advise but from what a local MGF club have said it might be the loom.

Yet more money.

If anyone else has any ideas please post them I would be really grateful

Mike
Mike

Is the engine idle unusual high ?

If so, then check for temperature sensor problems (Connection and Sensors themself)
Dieter

I agree with Dieter - test procedure can be found here Mike: http://www.mgf.ultimatemg.com/group2/common_problems/hgf_pages/related_problems_overheating.htm
Rob Bell

Well

Im really at a loss now the fault stopped for 2 days thne came back.

this has to be something so easy it is un true but I cannt figure out what.

thanks for the links Ive tried all of them and still no cure HELP........
mike

Mike,

Is the behaviour similar to the typical 'occasional high idle'? Is it usually to the same degree, i.e. consistently hanging at around 2000rpm, or does it vary?

The wiring to the throttle position sensor can fatigue over time; next time the car is idling high remove the inspection grille, reach in and give all the wiring you can see a gentle wiggle. If that has an immediate effect on the idle then that may be the root cause.

Is your throttle body the plastic OE item or is it alloy? The plastic bodies are particularly sensitive to the tightness of the jubilee clip clamping the rubber induction hose onto the throttle body. Loosen it off completely, then slowly tighten until you can't twist the rubber on the throttle, and then another half-turn of the screw is plenty.
Mike Hankin

Have you checked throttle is actually returning to its stop. On my I found that there are a kind of rubber seal each side on the throttle shaft which was squeaking and gripping the shaft. Engine off try opening & closing throttle from engine bay - stiff?

I cleaned out what I could of the throttle body bore and sprayed these seals and the shaft with an aerosol silicone lubricant, gave it a wiggle, put the rubber inlet back on, very gently on the hose clip and it's been fine for four years now.

Pete
Pete Tipping

This thread was discussed between 28/09/2006 and 23/10/2006

MG MGF Technical index

This thread is from the archives. Join the live MG MGF Technical BBS now