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MG MGF Technical - 48k service and trim heights

Hi all,

I just put my wifes MGF VVC 1999T in for a service this morning. It has done 22k miles and has had its 36k mile service last April. The service manager advised me to have the 48k mile service as it will be 4years old in April which has cost 130+vat. However, service tech. has phoned to say the car need the following aswell:

1 Bulb :-)
brake fluid (currently dirty) 16+vat
hose clips missing 24+vat

and he says the car is sitting very low (needed help to get on the car jack) and the suspension (hydragas) needs pumping up quite a bit - cost 43+vat.

All in all - approx 230/240 pounds for a car I thought was in pristine condition :-(

Should this be expected for age of the car and is the prices reasonable.

Recently, she has had some problems with the car revving at lights or when the car is started, but the tech said it would cost another 50 just to plug in a diagnostic machine to check the ECU and could be done anytime - so I declined the offer.

Any comments welcome.

MgF hyrogas will need pumping up from time to time.. 365mm From wheel arch to centre of hub is the measurement I think. If the car rides too low the geometry of the suspension will not be correct and will cause excessive tyre wear and poor handling charateristic. You may also need four wheel alignment.

On the other point one probably cause that causes the car to rev is a warped throttle body (not an uncommon problem), many people have replaced the original plastic items with alloy ones. Unfortunately the alloy ones are about 100 quid but you'll be able to get a replacement plastic one for practically nothing from many people on this board. I certainly have one available. Four bolts and a couple of screws and you're done.
tim woolcott

Speaking of the 48k service, where will I find a list of what should be covered in this?

Mark B

Hi Tim,

thanks for the quick reply.
We just replaced the two rear tyres because of poor wear on them, so this may have been caused by the hydragas settings. Hopefully this should fix that and
provide an even better ride :-)

How do I check for the warped throttle body - in the footwell or under the bonnet at the driver side and what does it look like? Is it that easy to replace? Where do you get the plastic or alloy replacements?

thanks again

Yikes - the dealer raised your car for you? What height is it now?

It should be pointed out that if the ride height is modified, then the tracking needs to be re-checked.

This was a job that perhaps they should have asked permission for, as you now need to spend another 40 quid on alignment...

>>Recently, she has had some problems with the car revving at lights or when the car is started<<

Tim has pointed out one potential cause of this problem - a warped throttle body. Unfortunately, an external inspection doesn't help your cause: it is impossible to see.

Replacement throttle bodies can be purchased from MGR, or indeed from a number of mg specialists including Brown and Gammons and Mike Satur (not to mention the MGF specialist autobreakers).

But you might not have a warped TB: this is usually caused by using a jubilee clip on the hose to the throttlebody. The original type clip is much better in evening out the clamping force - inspect the TB (seen through the boot inspection grille, towards the left hand side).

High idle speed can also be caused by dirty throttle bodies, a problem with the throttle position sensor, a problem with the coolant temperature sensor or a blocked IACV.

The throttle position sensor is easy to check: turn ignition to position II, and floor the throttle 5 times, and switch off. This will reset the throttle position sensor. It may cure your idle speed problem.

If a dirty throttle body, you can clean this using a proprietary carburettor cleaning spray - or alternatively, give the car a thoroughly good thrash to the red line, through the gears for 1/2 an hour (once the engine is warm of course!). Often clears crud out of the system.

A faulty water temperature sensor will make the engine management think that it is cold when it's not: result is that it effectively keeps the choke open for longer. This reduces fuel economy for starters. You may also see the water temperature guage creep up above its usual 'one gradation below half' position... More on this on

So plenty of areas to look at!
Rob Bell


If you would like a servicing schedule email me and I'll send one to you.


To see it if the throttle body (TB) is warped you could rotate the throttle butterfly in the engine bay by hand (it's the half moon shaped rocker with moves when the throttle pedal is pushed) , you may be able to feel the butterfly sticking inside.

If you want my plastic TB you're welcome to if for postage, but there is nothing to say it won't warp as well in time. For a new alloy TB try Mike Satur or B&G, or MGF centre you might get a secondhand one from the latter.

On a VVC you'll get a little more power too from the Alloy one, it's 52mm diametre rather than 48mm. Welcome to the dark side....
tim woolcott

Tim, you're a gent!

That would be great.

my email add is:

Many thanks
Mark B

Is that email address correct.... ?
tim woolcott

Ride height is 368mm, but what is 3mm between friends! This measurement is checked between the front wheel centre and the edge of the wheel arch lip directly above where the wing bends under. Of more importance is the need for the measurment and any adjustment to be done on level ground after a settlement period of at least 2 hours during which time the suspension not only settles but all temperatures stabilise.

Speaking of temperatures also brings in the fact that the measurment is applicable at a nominal 17 degrees C and that there is a float of plus or minus 10mm to allow for temperature difference based on a ride height variation that occurs at the rate of 0.6mm per 1 degree C change.

Rear ride height is incidentally 363mm, but since the front to rear on the same side of the car is interconnected what happens with system pressures at the frotn applies at the rear too. The rear measurment is mainly to cater for detecting specific displacer issues where usually a major difference in ride height for just that corner would be quite obvious.

Note to that there is more than one alloy throttle body aa all K series moved away from the original plastic one. In fact there are three basic types a 48mm from an 84Ps K 1.4, the similar looking body from the 103Ps version of the same engine and all 1.6 and sub 120Ps 1.8's. Then there is the 52mm body from the 135 and 160Ps versions.

The main problem here is that if you use an 84Ps body you will se a very serious loss of power as the design only allows partial opening of the throttle as a restrictor to keep power down to 84Ps!!!!

Brake fluid changes are a 24 month change item irrespective of mileage covered. Thus a 199 car should now theoretically be approaching it's second change!

Roger Parker

Yes Tim - that's the one
Mark B


"Ride height is 368mm, but what is 3mm between friends! " Naturally I had already factored in the ride height for winter temperature ;0)


I emailed you last night, hope you got it ok
tim woolcott


Just out of interest where are you taking your car for servicing?

David Clelland

Hi David,

Serviced at MRL (Macharg) in Castlebank Street. Do you have any comments about them -good/bad?

Guys thanks for the great replies - much appreciated.
One extra point - should I query the garage whether thay checked the tracking after raising the suspension?



It's never easy commenting on a particular dealer. I've not used McHargs other than to buy brackets for my hardtop. They are of course part of the Arnold Clark Group and while I don't have a problem buying a car from AC (bought several including my F) I've had problems with them servicing my cars in the past. I know that a few of the CSMGF guys from the Glasgow area use either Morrisons in Falkirk or Stirling (seperate companies). I use Morrisons in Stirling and I've always found them pretty good. I had a two year / 24,000 mile service done on the F a couple of weeks ago and it cost me 152 which included the brake fluid change. I asked them if they adjust the ride height as part of the service and was told no (I didn't want them to). I'd just fitted new tyres so I decided to get the car tracked at a place in Sighthill, Edinburgh. My ride height is near the bottom limit so I didn't get that altered. Combination of new tyres and tracking have certainly made the car handle slightly better.

Hope this helps.

David Clelland

Service prices quoted here seem very reasonable to me. Just had 2nd annual service (MGR dealer) on my Trophy (done 6k miles only) plus brake fluid change 226! And that's after (an alleged) 10% discount. This included things like "Gas Treatment" to clean and lubricate upper cylinder area, Wynns engine flush, 30 quid for oil, brake fluid, air and oil filters, plus the good old "sundries", environmental disposal charge and a mystery item called "Battery - B/Alarm" which I only spotted when I got home. Anyone know what that little "extra" might be before I ring the dealer on Monday?



Morrisons of Stirling (MG Dealer) carried out my second year service at 15154 miles

Service + Brake Fluid Change - 85.00

Brake Fluid - 4.76
GTX Magnatec - 26.41
Washer - 0.36
Cartridge - 4.29
Brake Clner - 2.5
Screen Wash - 0.75
Battery B/AL - 2.39

Lubricating Oils - 2.99

VAT - 22.74

Total - 152.69

The battery is for your key. It is changed at everty service so that you don't have problems getting into the car.

David Clelland

Thamks David - seems like you got a good deal.

This thread was discussed between 20/02/2003 and 23/02/2003

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