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MG MGF Technical - Rev limit too low?

I bought an MGF VVC today, but when I accelerate, it hits the rev limiter at only 5,200 RPM.

Just as the power is starting to come in, it dies a death! :(

Any ideas why this is and how it can be raised?

Cheers,

Chris
Chris Evans

Chris, if the rev limiter comes in way before the red line, if you bought the car from a garage take it back and ask them to sort it, if you bought from an individual then you'll have to find a decent garage with a MG Testbook to connect to your cars computer and get things checked out.
I'm assuming that this car is second hand as if it was new you shouldn'tbe exceeding 3k rpm.
Mike
Mike

Yes, it comes in way before the redline.

Bought it second hand. Mate who is a trader got it for me, he knows places that may be able to fix it, but just wondered if anybody knew of anything I can do.

Chris
Chris Evans

Chris, are you sure you bought a VVC ?
Dieter K.

Chris,
Not without a computer, Testbook software and the cable to connect to the ECU.
Just a question, are you sure it's the rev limiter ?, it has been known for the throttle pedal not to be travelling the full distance, have someone depress the throttle whilst you check the engine end to ensure the things is fully open.
Unless of course the cutoff is like someone put the brakes on.
Mike
Mike

Yes Dieter its a VVC, even says it on the top of the engine.

Its definately also the rev limiter, accelerates, then acts as if the power is being cut then put back over and over and sits at 5,200RPM throttle cable is fine.
Chris Evans

The car may not always be a VVC if a VVC plenum has been fitted as a mod, however assuming it is a VVc then it the early rev limit is usually electrical ie the cam position sensor connector might be faulty or if some recent work has been undertaken then the hydraulic controller connections could be incorrectly connected or a hydraulic solenoid at fault, a few simple checks may sort it out.Could even be spark plugs /leads, had the same with a VVC that had a plug out and was bouncing on the engine cover.
Hope your mate has the right contacts.
Mike.
Mike(another)

Woun't bore with my mad daubts, though please check the VIN and other details at Rob's site.
http://www.mgf.ultimatemg.com/facts_and_figures/spotting_the_difference.htm
Hard to hide last evidence is the 8th letter of the VIN.
T is VVC
G is MPI

On the other hand my quest to the speciallists.
Would the wrong ECU fit to a VVC engine as replacement ?
Dieter K.

Here's a quote from the MGF Workshop Manual:

"If the camshaft position sensor fails when the engine is running, the engine will continue to run normally in sequential fuelling mode. If the sensor fails before the engine is started, the engine will start, but run in group fuelling mode. The engine running in grouped fuelling mode can be detected by a reduced rev limit: 550/5800 in comparison to the normal rev limit of 7000/7300. Camshaft position sensor failure can be identified using Testbook."

HTH

Dave
Dave

Could be as simple as a faulty/unplugged connector on the cam sensor: it the "middle one" (I can't remember its colour!) visible when you tip the hood hood forward and remove the engine cover. Certainly mine was quite stiff to plug in...

If it IS this, I'd wonder why its been unplugged...

However, sensors failing aren't unknown an are quite simple (aka cheap) to replace. Check the archive - there's been a thread on it sometime in the last 6 months....

Neil.
Neil

Can position sensor is on the left hand side of the engine, in front of the throttle body.HTH.
Mike.
Mike

This thread was discussed between 22/02/2003 and 23/02/2003

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