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MG MGF Technical - ATTENTION:need your help

Right guys,

I was driving my mgf home last night and when i was in a low gear and low speed it keept jumping, and when still at a junction and i was reving it,the reve counter went up ok like normal but stopped on 2000 revs and slowly went back down to 1000, kept reving its self?

any surgestions need it back on the road

cheers
sarah blunt

Which model/year is your car Sarah?

The problem you are describing sounds a little like the problem Dieter had 'fun' trying to sort out - but the areas to check are the air filter, the throttle butterfly and the IACV...
Rob Bell

mine is 1.81 n reg about 1995 1996
sarah blunt

Sarah, thanks. Will's suggestion of using some contact cleaner on the electrical connections to the TPS and IACV seems like a good place to start: easy and cheap to do.

Failing that, it could be that oily/resin deposits have deposited around the throttle spindle or in the IACV. A proprietary carburretor cleaner would be good to clear all these, and would be my next step.
Rob Bell

Yep, electric contact troubles was the 'very fun' Rob reffers to.

Drove me nuts for more than 1 year until I found the solution at my car with re-routing the wires to the black ECU connector in _smooth_ curves.

Image from the ECU bracket rear side.
http://www.mgfcar.de/mems1.9/2_off_Dsc02518.jpg
The plastic stud (grey) was loose and the loom on the right going upwards to the ECU connector had come downwardsand was pulling at the wires.

This all after several works at the TPS (throttle position sensor), _useless_ change of the brown coloured ECU Temperature Sensor, cleaning Sensor contacts etc.

The IACV might be sticky from any dust and oil derivates though.
But at first I'd have a look to the ECU connector and the thin wires leading into the the connector. Any _pull force_ may be transferred to the fine blades/sockets end bent them in unwanted direction (result=high contct resistance). Bad crimps may be another cause)
Wherein the sensors own resistance is low with app 2k Ohm only and lowest distortions will cause the ECU to switch to save running mode.

This site covers some of my _desperate_ attempts to get behind the problem.
Ignore the theories mentioned there about sticky butterly and vacuum leaks.
But check the MPG movies linked on the left.
http://www.mgfcar.de/high_revs/index.htm
Apology, at any time I'll sort it)

HTH
Dieter

Dieter K.

cheers guys appreciate all your help and knowlege always helpfull,i took it out for a spin, got it reving in low gear for a while just to give it a clear out, it hasnt had a service for 10,000 miles so gonna get it in next week, think its just clogging up with crappy dirty oil.but i will impliment all the above jobs to get it spot on.

cheers dudes
sarah blunt

This thread was discussed between 10/05/2005 and 11/05/2005

MG MGF Technical index

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