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MG MGF Technical - High idle speed at beginning of journeys

Hi technical people,
My MGF is suffering from erratic idle speeds, anywhere from 600 - 5000 during the first 15 minutes of a journey. After that it seems to settle down to a steady 800.
Any suggestions of what the problem might be.
Mark
Mark

either a sticky throttle, a fault with the throttle position sensor, a fault with the Idle control valve or a temp sensor fault.

for the first two, replace the throttle with a new shiney alloy trophy model, for the last one check the readings against Dieters web page and see if they look reasonable. For the one in the middle, try clamping the hose on the IACV and see if the problem persists or gets worse.

Will
Will Munns

Thanks Will. I'm pretty sure it isn't the temp sensor, since I had that replaced fairly recently........Sounds very sticky throttle like
M
Mark

If it's going to 5000RPM then it's almost certainly a sticky throttle !
Has the car been worked on recently ? Servicing / Modifications ?
It may just need cleaning.

Steve
Steve

OK...went to my MG dealer to have this looked at, and this is what they discovered. The ECU in the car is not an MG original, and has been wired in so that the immobiliser is disconnected (which is rather disturbing). They cannot diagnose the problem because the ECU tells them nothing....where do I go next...I don't particularly want to spend lots on a new unit..........grrr
Mark

Mark, find out what ECU it is, if it's an Emerald then Whee hee, you can download the tools and you have a much better solution!

Will
Will Munns

Will...OK, I am offcially a real niice (as you ay have guessed. How do I best get to the ECU. I can the see if it has a label or some Markings...and then what.
Mark

Sorry, Just read my last comment on this thread. I seem to miss every other key as I was typing:
What it was meant to read was:
I am officially a real novice (as you may have guessed). How do I best get to the ECU to see if it has any labels or markings.....an if I can, what can I do then
Thanks
Mark
Mark

Mark, Pop the bonnet and take the grill off (the black grill with 2 plastic coverings).

Then on the left side there should be a silver flat box looking thing on the boot side of the wall. :-)
If you look at Dieter's site, you will be able to find a lot of photos...

Hanah Kim

I know which bit your talking about...I'll have a look later. Can someone let me know the web address for Dieter's site. I see it mentioned everywhere.
Thanks
Mark
Mark

Mark,

www.mgfcar.de (if I remember rightly !!)

Hope you get the problem sorted !

Tony





Tony Lynch

This thread was discussed between 11/09/2002 and 16/09/2002

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