And for my next problem!

[chris.richard]

Where to put my Lambda probe. (Steady Bernard) Does it need to be exposed to both banks of cylinders, or will putting it in one pipe be OK? If it needs both, would putting it in the silencer box at a position straddling the two sides of the cylinder do, or is that too far from the engine, and not be fresh enough exhaust? (Fresh exhaust fumes? - Shome mishtake shurely, Mish Moneypenny?)
In that case I'll need to form some sort of cross tube, but it would be a different distance from each manifold, -would that matter? Is a cross tube of great benefit anyway?

So many questions, so little knowledge. Any offers out there?:confused:

[Stratos]

I've only got one. It's direct into the rear-most manifold.

But, mine was only used for mapping the engine when it was installed, and my engine is a 12v.

On the 24v, I believe the ECU actually uses the Lambda Sensor to control the engine.

Jerry has a 24v engine fitted to his car, so I suppose he is best placed to comment.

[Stratos]

I'm sure David May will also chip in, as he probably knows more about this than most of us.

[David May]

Oops, do I detect a scent of boredom with my electrical comments? It's only a job after all!

There are lots of different types of lambda sensors and several ways of mapping them into the engine control algorithms. If you only have a single one on a V6 engine, then it's probably quite basic and the mounting position will have little or no effect on the running (as it is they only come into play at low - and part-throttle openings. If the car is to be fully homologated and pass a full emissions cycle test (something only manufacturers or importers do), then it needs to be installed precisely and well mapped, but if it's only to pass the garage exhaust gas sniffer test, its much less critical as the difficult warm-up phase is not measured. They need to be close enough to the manifold to heat up quickly (even if electrically heated) but not subject to excessive temperatures (over 1000C) or irregular gas swirl.
It will almost certainly be too cold in a silencer (the garages usually test at tickover and just above and it won't get hot there, and even a heated sensor may even get cooled down) so the front-pipe is the usual choice.

On USA-spec 24V engines, they are both mounted at the bottom of the manifolds, just below the front-pipe branches.

Watch out where you run the cables - only the first part is asbestos lined and you won't want to melt the connectors or break the wire with excessive movement! The nose of the sensor should protrude into the gas-flow, and don't put it on the bottom of a horizontal run when condensing water will run into it.


Dave May

[Stratos]

Originally posted by David May
Oops, do I detect a scent of boredom with my electrical comments? It's only a job after all!

Dave May

David,

Exactly the opposite. It's nice to be able to call on someone with your level of expertise in this field.

[lpriestland]

The nose of the sensor should protrude into the gas-flow, and don't put it on the bottom of a horizontal run when condensing water will run into it.

Nice one David, I'm just about to insert a Lambda into my exhaust and hadn't considered this. My intended location was on top of a horizontal pipe but it's good to think these things through, similar to 'measure twice, cut once'...

[Bernard]

Where to put my Lambda probe. (Steady Bernard)..................................mmmmmmmm mmm looks like I'm getting a reputation !!!!:D
Bernard