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 - Lambda, are they all the same ?

I'm currently upgrading my stock exhaust manifold to a Piper 4-2-1 manifold. I can't unscrew the lambda like I allready suspected so I sourced a new Lambda on Ebay some time ago. They seem to be different:

Stock:
MHK10006 (used until VIN YD522572 for MGF VVC and MPi)
LSH6
0 258 003 229
12V

"Ebay":
MHK100840 (used from VIN D522573 and on for MGF VVC and MPi)
LFS4
0 258 006 127
12V

The connector is different but this can be changed over with the old one. The wires which come from the lamda have the same color:

grey
black
white
white

Is there any difference between the white wires ?
(are the used for the pre-heating of the sensor ?

Any thoughts are very much appreciated. I'll continue un-doing some engine mounts now ;)

Sander

I canīt help you on this one Sander.
but two things seem clear:
1. two wires for heat up, another two for measurements?
2. you have a spare manifold which Iīm desperate to get my hands on ;-) *LOL*

cheers,
David Peters

IIRC all 4-wire lambdas are effectively the same - although the colour codes may differ. The two white wires are often grey for example, and are the wires that heat the sensor. The remaining two are the signal wires.

It boils down to wiring up the connector appropriately :o)

I think that Tim had the diagram for wiring an aftermarket Bosch Lambda to the Rover loom?
Rob Bell

The 4-2 part is in place. The "1" part will follow after I've reconnected the Lambda. I think I'll just connect the colors the "logical" way. Since white will be for heating I don't think the polarity will matter ?

If I screw up I'll just have to call Bruno with the T4 ;)

Thanks for the input guys !
Sander

The 2 white cables are for the heater. Can be connected either way as the heater element is "floating" with no internal conn. to ground.
The black cable from the new sensor should be the signal out and the grey is the ground,(outer casing of the sensor.)
To confuse matters further (!) there is a plug for the sensor where colours changes....

Sensor white = blue/red at plug
Sensor white = black at plug
Sensor black = grey at plug
Sensor grey = light green/grey at plug

If you dont get the correct mating plug do crimp connections as per above. Good luck / Carl.
Carl

Hi Carl, I've copied the colors form the old connector so I should be o.k. Thanks for the diagram.
My F seems to be running fine with the new lambda.

I still have one (small) problem though. I can't get the connection with which the 4-2-1 is connected to the flexible section air-tight. It's leaking quite allot. I've tried to connect it as "in-line" as possible and even added fire gum to fill in potential small leaks.

It seems as though the "V" clamp which is supposed to "pull" both sides against each other clamps on the tube of the exhaust instead of the "slopes" of the "trumpet" shapes. (Hope you can follow me ;)

Has anyone experienced someting similar ? What's the best way to fix it ?
Sander

I had the same problem with my Janspeed manifold Sander.
On my last car it sealed fine, but when it was removed and fitted to my current TF I too couldn't get the flexy to manifold joint to seal.
My solution was almost identical to yours too LOL. I removed the clip and spread fire gum all the way round the joint before refitting the clip. Its been fine since. I also put a bit of thread lock on the tightening bolt as I found it had a habit of slackening itself off over time.
Only problem I now have is that the flexy is very close to the rear tie bar and knocks against it at low revs (I assume this is a TF only problem) so I may have to come up with an additional exhaust steady.
Steve White

Well, it seems like I fixed it:

I've removed the flexipipe. The flange was a little "dented" where the clip once was so I hit it back into shape with a hammer. When holding it into place I noticed the cat was sitting relatively high. Too high for the flexi2manifold joint to sit 100% naturally. I removed the MK1->MK2 adapter pipe+cat bypass from the Janspeed and refitted it so that the whole converter-cat assembly could "hinge" over the adapter's connecting joint. Positioned it in such a way the flexipipe would sit as naturally as possible and put everything back together with (lots ;) of Firegum.

This time I let the firegum vulcanize for about 30 minutes instead of starting the car immediately and just relying on the heat

Everyting seems fine now :o)

Thanks for al the advise !
Sander

This thread was discussed between 26/06/2006 and 27/06/2006

MG MGF Technical index

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