MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGF Technical - Exhaust solenoid

Hi guys!

I'm getting more and more excited about my 3 weeks old TF 135, and I learn a lot about it thanks to Rob and the BBS.

For instance, I discovered in a post that there was this solenoid on the right exhaust, and went to check how it was working. Well, quite surprising, my rignt exhaust keeps looking brand new, is not even really hot even after a sporty ride... Judging from the post, it should open after 4000 RPM, so decided to test it. I asked "Mrs Fred" to accelerate up to 5000 rpm while I was watching it (no gear engaged, of course!)... Nothing... Is that normal?

Another question: what are the concequences if I disconnect it: performance? sound? nothing?

Thanks

Fred
Frederic Lemaire

We're not quite sure when it opens, it may be load related as well, disconnecting will have no effect except a very little more power and a little more noise.
Will Munns

Sounds to me as though it is not functioning properly Fred.

What happens when the plug is disconnected? This should result in the flap staying opening. If the flap remains closed (no exhaust gas out of the RHS tail pipe), then the flap has jammed. If is a simple mechanical device, so you could probably easily 'unstick it' - or get the car looked at under warranty.

If it does open, then for some reason the actuator is not functioning properly. It uses engine vacuum to sense the rpm/ load - so there may be a leak in the vacuum pipe or a poor connection leading to a loss of vacuum.

Fiddly area to access though! Good luck, and keep us posted! :o)
Rob Bell

Following the earlier thread on this subject, I disconnected my solenoid....then my friendly MGR techie blamed a subsequent engine warning (see another thread) on it being disconnected (obviously couldn't find the REAL cause!!!) and so he re-connected the block.

The thing is...altho the wiring is back in situ, the flap appears to still be open permanently!!!

So everyone's happy!!!
SimonKE

Simon, if your flap had been 'open' for a long time it's possible that sufficient corosion may have taken place such that the mechanical bits stick open.

I had intended to re-connct mine from time to time to 'exercise' the flap and avoid such an eventuality.


Fred, I agree with Will. I think opening depends on more than just reving stationary car engine.

To prove if its working or not may mean Madame Lemaire sitting in the boot while you roar up and down le rue.

If she objects you could instead wedge some paper up the pipe and see if it gets blown out.

jt
John Thomas

>It uses engine vacuum to sense the rpm/ load - so there
>may be a leak in the vacuum pipe or a poor connection
>leading to a loss of vacuum.

Not quite, the vacume operates the flap, but the choice to open is entirely electrical and done by the MEMS
Will Munns

Vacume Will? ;o)

Okay, MEMS has control over the valve, via that disconnectable plug, you're right Will. Still dependent upon rpm/load though... ;o)
Rob Bell

Yep, but I can spell dyslexic (cos it makes sense, if you know what it means!)
Will Munns

Wait a minute,has somebody just invented the first 2+2 MGF? this could be useful!
M J Gibbens

This thread was discussed between 11/07/2003 and 12/07/2003

MG MGF Technical index

This thread is from the archives. Join the live MG MGF Technical BBS now