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MG MGF Technical - MG TF Sticky throttle

Just bought 04 TF, Brilliant..But.Throttle action makes for tricky take off. Have lubed most parts that I can easily see, to no avail. Any advice please.
Mark H Williams

And I thought it was me - same year car, same problem - I eagerly await some advice as well!!

Colin
C Martin

Probably replacement of the cable.
http://forums.mg-rover.org/showthread.php?t=312940
You can get cable oilers which pressure feed oil down the cable - a useful aid with the bonnet cable - but sounds as if it may be too late for that.
Charless

Thank you Charless. I have ordered part and will follow your excellent directions.
Mark H Williams

C Martin, Please let me know how you get on. Sort of pleased we have the same problem! thought it was just me!
Mark H Williams

You might find it improves a whole lot if you reset the throttle position - TPS reset.

Switch on the ignition so the red lights all come on but don't start the car, fully depress the throttle 4 times in less then 20 secs and switch off again.

If my car has been unused for a few of weeks it seems to forget and is a pig to drive with a real on/off throttle response - this is a magic wand!
Tony

I had much the same problem, mine turned out to be the butterfly in the throttle body was sticking and gummed up. After removing it and a through clean with carb cleaner all was well.
AndrewMc

"""Thank you Charless. I have ordered part and will follow your excellent directions."""

I should love to bask in your generous praise but am not CJJ on dot org! I agree with you, he has done a very good job though! There are loads of very good 'how-to's on dot org, but also a loads of irritating chatter too - which is why I prefer this site!
There are a couple of other cheap potential solutions to try from this thread too - well worth a go before you break the seal on the new cable! Good luck.
Charless

I reset the TPS as advised above, I think it may be better but difficult to be sure. I will clean the butterfly when I get a spare moment.

Colin
C Martin

I also reset TSP... no improvement. Next step to clean butterfly. Now got juddery clutch ! What have I bought?
Mark H Williams

The fitting instructions for a K&N air intake filter make it plain the intake tube clamp at the throttle body must not be overtightened - for fear of distorting the throttle body. The fragility of a standard plastic TB applies regardless of fitting a K&N or retaing the standard setup. Perhaps the air intake tube clamp has been overtightened in your case and the TB is now distorted?

I believe the band should be tightened to just grip the TB then no more than one full turn after that. If your clamp is tighter it's likely that TB distortion could be your problem.

It might be worth a go to slacken the band clamp, rotate it 1/4 turn and retighten to see if it resolves the ovality that may have happened. You may need to remove the band and refit the other way round, in order to get access to the clamp's screw from the engine guard side which will avoid removing the engine access panel.

As for a juddery clutch - are your sure it's not loose or worn engine mounts or a missing top mount nut at the front on the engine (r/h from the rear view). The mount is removed when performing a timing belt change and may not have been refitted properly.

Jeff

J Lennon

Thanks Jeff. Car goes into my local garage [Sussex Cars] on Thursday armed with your and others info to follow.
Mark
Mark H Williams

Thanks to all and Clive at Sussex Cars my TF is now so much easier to drive. Butterfly seemed to be the culprit, but I'm sure you will hear from me again!... A few words about Sussex cars of East Preston owned by Andrew Shipp.. Very helpful, very understanding, very reasonable rates, excellent mechanics, Clive and Liam. Sign up for "Mates rates" and get 10% discount.I don't work for them!
Mark H Williams

Good news Mark. Do you know what they did to the butterfly?

Jeff
J Lennon

Jeff
Basically gave it a good clean with carb cleaner and an old toothbrush, also checked the air intake filter as per your suggestion. I took the chance to dribble oil into the throttle cable whilst the mechanic {Clive} had his back turned!
Mark
Mark H Williams

Thanks Mark.

Whilst my throttle is not (yet) sticking, I noticed the butterfly was grubby when I changed air intake to K&N type and made a note to self to fix it. Now I know howto, thanks. I was told that the throttle cable can be set too tight and this causes stutters when the car is warming up. Dr Dave had a look a few months back and backed the adjuster down a slot to get some slack in it at rest. No more stut.ut.ers!

Jeff
J Lennon

Hi Jeff
Don't want to bore everyone but do K&N improve performance?
Mark H Williams

Yes!

Especially after 4,000 rpm if you have a VVC.
On light throttle you'd not notice it.
If you feel like giving the motor a thrash, the induction roar cuts in and the car accelerates siginificantly better. Great noise, you'll love it.
Back off the throttle and the roar ceases.

IMHO if you can improve the breathing THEN you can set about improving the exhaust. The K&N gets cold(er) and thus denser air into the engine via a direct route that does not involve a load of pipe bends. Of course, if you mod the car to improve performance, you might invalidate your insurance, so do check first.

Fitting a K&N is easy. Whip out the engine access panel, decouple the original air intake pipe from the throttle body, undo the air box clips and remove it's paper filter. Unscrew the air box fixing bolt and remove the box base from the car. Decouple the plastic elbow from the resonator box. Leave the resonator box in place.
The kit comes with instructions for an MGF/TF - basically fit the pair of flexi tubes (stretch to extend them first) through the gap left by the removed resonator box elbow and bend them to face front under the car. These act as a cold air feed - most effective when moving forward at speed. With the supplied straps, fix the tubes to the underside of the vehicle. Fix the cone, tube and pipe as an assembly to the throttle body using the jubilee clamps supplied. Bend then fix the cold air tubes with straps supplied so they face the cone approx 4 inches distant. That's it! Refit the engine panel and enjoy better performance. If you can restrain yourself to drive it as you did before (grin) you'll get more mpg.

Oh! Before you start, get a small pack of heavy duty plastic tie straps (as per the ones in the kit). I used more of them to make a neat/secure job. You can get them from Maplins, B&Q etc. I got my K&N from Greg at http://www.sussexclassiccar.co.uk for sensible money(other sources are available of course).

There's a decent series of articles on air filters and howto's at http://www.mgf.ultimatemg.com/group2/air_filters/

Jeff
J Lennon

Snap, funny as it is such an easy thing to fix. Like most of the above I considered new cables etc. I had the TB off for a different reason when I noticed all the gunk.

I tend to clean mine about once a year now.
AndrewMc

Thanks to all for your help on the above topic, but I think I will be back!
Mark H Williams

This thread was discussed between 27/08/2009 and 22/09/2009

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