Installing lambda sensor from scratch

sladey · Post by **sladey** » Tue Jan 05, 2016 7:58 pm

Some of you will have seen my other posts where I've installed a second hand CANEMS ECU. The installation has gone well and the car is booked min for a rolling road setup some time next week.

My car has never had a lambda sensor (I say never - by the time I bought it there wasn't one there) but there is a fancy fancy wide band lambda sensor included with the kit. So I'd like to fit it if possible to take advantage of the oxygen reading in tuning the car. This is what came

Here is the sensor.

My question is - as I've not had one installed before I'm going to need to weld something into the exhaust. The sensor part will then screw into that. However I've not found anywhere that talks about what is needed. In the photos above there is that threaded collar that the sensor screws into. However if I welded that in the sensor wouldn't be exposed to the gases.

I'm guessing I either need to get a nut of the right diameter and weld that into the exhaust OR chop off part of the threaded tube and weld that in - allowing the sensor to poke into the airstream. Can anyone confirm I'm on the right lines and/or point me to online advice on this - whenever I search I keep finding stuff about replacing the sensor - which all assumes you've already got the threaded part set into your exhaust

With regard to where to fit it I'm thinking onto one of the 'stems' leading into the muffler - that will cover 3 header pipes output so should give a reasonable reading.

Thanks in advance for any help you are able to give

Oh and here's a pic of the rest of the sensor kit

210bhp · Post by **210bhp** » Tue Jan 05, 2016 8:48 pm

You really need one sensor on each bank. My nuts (from memory) were welded onto each heat exchanger about two inches back from the flange with the exhaust. Ask James Hot66 or JohnM. They have both got them I think.

Regards
Mike

impmad2000 · Post by **impmad2000** » Tue Jan 05, 2016 8:57 pm

I' d shorten the boss so that the sensor sits in the gas flow. the photo shows where the boss's are welded in just before the exhaust flange to silencer. Keep the innovate controller away from heat sources, these can die if they get too hot, I saw one mounted above the silencer !!

shambly · Post by **shambly** » Tue Jan 05, 2016 9:01 pm

The LC-1 has been superseded by the LC-2 now. Looking at an LC-2 I have here, it is supplied with a simple 1" mild steel threaded tube much like what you have to weld into the exhaust.

We often, though, supply a stainless alternative to the mild steel bung when LC-2s are used by our GaugePilot customers (as they often have stainless exhausts).

Item 111762435609 on eBay is the sort of thing - its designed to be welded at the flange with the smaller OD within the exhaust pipe putting the sensor nicely in the flow. (no affiliation to the vendor and I haven't checked out the item in detail - I cite it as an example.)

The lambda sensors are quite sensitive so place it, and the controller, following Innovate's recommendations. Also avoid starting the engine from cold having had the ignition on long enough for the sensor to heat up (cold condensation thrown at the hot sensor can kill them). Having said that for some people they seem to work forever without issue and for others they cause nothing but trouble. I killed one sensor over 10 years use in my Chesil.

Simon

Splitpin · Post by **Splitpin** » Tue Jan 05, 2016 9:18 pm

I try to fit them so the wire end is higher than the sensor end to keep condensation out. Having the sensor further into the flow can cause over heating of the sensor in my experience.

I used them a lot a good few years ago

hot66 · Post by **hot66** » Tue Jan 05, 2016 9:44 pm

Mark, I've emailed you a pic

... I have 2, monitoring each bank which has proven to be very useful ... Both are connected to a dual afr meter located in the glove box rather than being part of a FI system.

Mine are mounted at approx 45deg , wire facing up. Boss welded to ssi , roughly in line with the rear of the rocker cover ... All this done by Neil Bainbridge

smallspeed · Post by **smallspeed** » Tue Jan 05, 2016 9:44 pm

Make sure you follow the correct set up instructions too BEFORE you install it into the exhaust - they need to be calibrated with the sensor in open air as a baseline and its best to do that in open air and not installed into the exhaust with the engine off

In terms of installing the threaded boss - weld on and then drill through BUT make sue you look at how far the sensor is supposed to poke out into the exhaust gas "stream" - too far and it will burn up/get coked up, not far enough and it won't read correctly.. Its fairly easy to grind it down a bit or (if you have access to one) slap it on a lathe

As Tim says keep the controller inside the car if possible to keep the temp down and keep it dry

Regards one vs two - if you're not controlling cylinders or banks individually you can get away with one - for example if you're wasted spark ign in 3 pairs and injectors on 2 banks then it should be fine.. I've always got away with it anyway.. If you've got no cat and you only have one tail pipe then you could always fit it after the two banks merge?..

sladey · Post by **sladey** » Tue Jan 05, 2016 10:21 pm

Wow thanks guys - serious amount of useful information there. I've ordered the flange and some stainless MIG wire. At the week-end I'll weld it on.

I'll have a look at calibrating it before I fit it - perhaps even read the instruction manual

I'm going to stick with one for the time being - I might look at fitting it on the single tail pipe provided I can get it in behind the bumper

smallspeed · Post by **smallspeed** » Tue Jan 05, 2016 11:05 pm

Might be a bit far away from the engine but worth checking - I've fitted one right after the x-pipe on a bmw which is a good meter from the cylinder head and it works fine so might be ok..

sladey · Post by **sladey** » Wed Jan 06, 2016 7:41 am

Thanks for the response again. Done a bit more searching and found a useful guide to placement

http://wbo2.com/lsu/position.htm

So I reckon the tail pipe will be too far away and won't warm it quick enough - I'm going to go for one of the muffler input stems probably - will have a good look around at the week-end

smallspeed · Post by **smallspeed** » Wed Jan 06, 2016 8:34 am

that's a really useful page actually especially the out of car checks!..
I think the locations Tim and James have sounds best for a 911
If you decide you want two drop me a PM as I have one sitting on the shelf that's never been used. Its a couple of years old, but literally new, in the packaging. I can get them from the US when I travel with work so can easily get a replacement if I need one another time

sladey · Post by **sladey** » Wed Jan 06, 2016 12:42 pm

thanks for the kind offer. I think I'm going to stick with the one for the time being. At the moment it's running pretty well with none, so 1 should be an improvement, and I can't see from the manual how you'd connect two sensors

sladey · Post by **sladey** » Wed Jan 13, 2016 7:16 am

smallspeed wrote:that's a really useful page actually especially the out of car checks!..
I think the locations Tim and James have sounds best for a 911
If you decide you want two drop me a PM as I have one sitting on the shelf that's never been used. Its a couple of years old, but literally new, in the packaging. I can get them from the US when I travel with work so can easily get a replacement if I need one another time

You have PM

I installed it at the week-end (viewtopic.php?f=28&t=6932&start=1440) and I'm not convinced it's actually working.

I've got the rolling road tomorrow so if I could borrow it today just in case?

DDK - Die Deutschen Klassiker