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MG MGF Technical - vvc running problems

Hello i have a bad running problem with my vvc engine, i know a few people may not aprove by this but its in a metro, most people dont want to know at this stage but i need help!, i have poped down to my local rover garage and the teck there said that the running problem is that the vvc gearing at the top of the engine has packed up or sticking ! he said that it is stuck in max valve lift and causing the engine to run very lumpy on tick over , and its not very good on fuel and also very flat on bottom end power ! i have carried out this converion to 4 metro's now and have never had and problems , and they have proved to be a very good engine ! the only mods that have been carried out to the car is no cat, comp exhaust , viper a/filter and a lightened flywheel, at first i thought it might be the flywheel at fault , as i thought it might be to light , i am using the r65 1.6 flywheel not the opg1 if thats any help!

all advise will be greatly recieved

many thanx ian
ian parkes


The best bet would be to get the garage to plug it into the testbook(tm!) which will log what fault is causing it. Possible causes are wide and various... but my guess would be some form of sticky/broken VVC solenoid. I'm surprised that the VVC mecahnism has stuck "on" as your garage has suggested. Only the testbook will confirm.

But I may be wrong. :-)

Are you sure it's VVC related and not some sensor problem that's causing the engine to default into "get me home" mode?

P.
Paul Nothard

Hi There

Dave had a similar occurrence last thursday half way through our activity at Northweald..

He put it in for a testbook and this is the reply posted in the thread 'handles like a different car'


>>OK, so the conclusion, for those interested, is that the dealer testbook showed a faulty "VVC Spool Valve and two solenoids". Some sort of hydraulic control mechanism for the VVC system. Anyway, £220's worth of fix - split roughly 50:50 parts:labour. Ouch!<<

Hope this helps

Stu
Stu

Ian,

Sorry I missed this thread - Stu is right, the situation sounds very similar. My symptoms were a very distinctive 'heartbeat' sound coming through the exhaust at idle, with idle revs up at 1100 instead of 900. When moving the car was fine above 2000 revs, but below this it was lacking power and would run roughly at times.

If this sounds the same then the diagnosis that Stu copied from the other thread is the one to look for - VVC spool valve and solenoids - well done Paul for coming to the same conclusion. I'd never heard of this problem before. Paul, I guess you must have - is it common?

Dave
Dave

Could be the flywheel differences between the 1.6 and 1.8 ie crank sensor triggers.
Mike.
mike

PS assuming you have all the wiring and timing correct?
mike

1.8VVC in a Metro? Wow, that'll be an interesting car when you get the project sorted Ian!

Good luck with the fault finding!

BTW When Dave was searching for causes of the problem with his VVC, a number of areas were suggested:

Loose cable connector to individual sensors (Dave, didn't DVA suggest looking at the throttle position potentiometer?)

Inlet manifold leak

Neil suggested to "check the cam sensor plug and socket - right on top of the cam cover (left hand one as you look at it from the rear of the car - the 3 right hand ones are on the VVC unit)." This solved the problem on his VVC.

And Mike's suggestion regarding the crank position sensor certainly sounds like an important area to investigate (it's located, as I am sure you know, in the flywheel...)
Rob Bell

Rob,

Yes, of course, it's worth checking out all the sensor connections first. I was also advised to check breather hoses and vacuum hoses for air leaks or blockages.

Dave
Dave

<<<1.8VVC in a Metro? Wow, that'll be an interesting car>>>

blimey! does it have brass handles on the sides and a nameplate on top all ready?

t ;-)
tony

For clarification, not crank sensor,it wouldn't run if this was faulty. The crank sensor triggers on the flywheel.
mike.
mike

Hello lads thanx for your response, i have checked all conections and they are all o.k , the car can not be put on to test book as it does not have the diag conector!:( i think the problems are the same as dave ! mine is ticking over very lumpy and it is at 1100 rpm , very flat off the bottom end , but o,k when reving ! i have carried out 4 vvc conversions in to metro's and 1 standard 1.8 and this at the moment is the slowest :( , not very impresed at the mo ! like i said a first i thought that the flywhhel may have been to light and causing this problem, but after talking to the engine place that carried out the mods to the flywheel they said that it would not cause this problem ! the car is also not very good on fuel ! dave did u have this problem with yours ?

again many thanx

ian
ian parkes

Ian,

I'm afraid I can't help you on the fuel question, as it was in the middle of an activity day at North Weald airfield when this happened and the ragging the car was getting would have dropped the fuel considerably anyway. I filled up just before and I'm yet to fill up since.

Dave
Dave

Hello thanxs for all your help could uyou please advise me where i can view this thread that was mentioned :VVC spool valve and solenoids , many thanx ian
ian parkes

Ian,

It's on this Technical Board and called "Handles like a different Car !!!", but there's nothing more there than has been posted on this thread i.e. the symptoms I had, that the Spool Valve and Solenoids was the diagnosis from the MGR dealer and that they replaced the part. Do you want the part number?

Dave
Dave

yes please dave if you dont mind ! thanxs

so all the faults that i have mentioned seem to be the same or similar faults that you had ?

thanx ian
ian parkes

Ian,

Your words "...ticking over very lumpy and it is at 1100 rpm , very flat off the bottom end , but o,k when reving..."

My words "...the car running perfectly above 2K. Below 2K it is lumpy and lacks power. At idle it has a distinctive heartbeat drum in the exhaust note and it's doing 1100 revs rather than the correct 900..."

Seems pretty similar to me. Do you hear what I've called the 'heatbeat' in the exhaust?

Part number = LGH101350 @ £85.74 inc VAT

Dave
Dave

hello yes i am getting a thump thump all the time through the exhaust !

many thanx ian
ian parkes

Ian,

OK, so we have a 3 out of 3 match on our symptoms. Looks quite convincing, but an expensive part to replace on spec. Shame you can't get it on testbook. Let us know how you get on.

Dave
Dave

will do and thanx again mate ! much appreciated


thanx all ian
ian parkes

This thread was discussed between 04/12/2002 and 06/12/2002

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