wideband o2 setup?

just a quick one - how far into the exhaust stream does the sensor have to sit? ie how proud of the inside of the exhaust?

 

The bung should be the right length. If its going to be close to the head an extender bung can be used to protect from heat.

 

the sensor will be sited just after the manifold/downpipe flange. the bag the bung came in has 'extended bung' written on it, and the bung is 25mm long so that sounds ok. innovate recommends making up a heat sink out of some steel plate to protect the sensor.

including the thickness of the pipe itself this would put the tip of the sensor flush with the inside surface of the exhaust. does that sound about right?

 

That sounds ok, i doubt very much you need extra heat sink tho

 

Yea just use what they give ya. Heat sink is more for close to turbo installations

 

cracking, thanks guys.

 

as i found out ooppps

 

oh dear, what happened?

 

If you want fancy gauge then you can get xd-1 gauge, i use one it has digital readout as well as led-s with programable colours and it simply plugs in to the terminator socket plus 12v supply

Also has calibration button built in and you can set alarm function on it

If you get bored of it it can be configured into some other gauge like a rev counter

 

i had mine on the elbow of the turbo outlet,but the heat of the turbo caused the senser to fail. i now need a heat shield bung, to bring it away from the exhaust pipe but still allow it to read the gas

 

Thats why i mounted mine in the existing lambda hole away from the heat. If you read the instructions its quite clear.

 

well it looks like i'm going to have to remove the downpipe to weld in the boss after all. i was a little unrealistic thinking i could fit it with the downpipe in situ, and still get a good quality weld. with my limited welding skills anyway.

 

i'm now in the process of fitting the o2 sensor, but i have a quick question.

i welded a boss into the exhaust under the gearshifter (the only place where there was room for the sensor to sit), but there are a couple of joints upstream of it. i could theoretically weld these, but it would mean several hours of extra work to fit the pipe in one piece.

so is it acceptable to use exhaust pipe joint sealer upstream of the o2 sensor - as long as it all seals correctly and doesn't allow any o2 to leak in will this be ok?

cheers,olly

 

up stream is to be avoided. it would ruin the sensor if it got any one it.

your car is a syncro isnt it? other wise i would have said put in the down pipe under the manifold connection

 

I have mine in the original location. There is the joint just before it but its not leaking and is a flange. Slip on joints are more pron to leaks therefore false readings.

 

****. i have actually fitted it all together this morning, pipe sealer on the joints and everything. bugger.

i've got the gauge running and it's reading fine, if any of that sealer flakes off would it really contaminate the sensor? it's the white kind of sealer that goes crusty when it sets.

should i be seriously thinking about pulling the exhaust off and welding a boss into the manifold/downpipe flange after all?

how frustrating.

 

dont pull it apart, just run it for a week or so, then take the sensor out and make sure its not got any paste stuck to it.

 

thanks for putting my mind at rest, i'd pretty much decided not to bother doing it again anyway, and just get another sensor if it goes. slip joints aren't leaking at all, but i'll keep an eye on them every now and then. next week i'll pull the sensor out and inspectigate, but it doesn't really poke down into the exhaust stream that much so it should be fine.

on a more positive note i've got the gauge installed nicely. off for a drive tomorrow to see if there's any need to fit the 16v WUR i've got knocking around.

 

just taken it for a spin to the offy & the downpipe's knocking against the bulkhead, which means disturbing all the slip joints to re-position it, which means if it isn't sucking air in now it will be then. so off with the whole lot again tomorrow. i'll move the sensor bung to just after the manifold like i'd planned to start with. bit of a faff but i suppose it's worth doing it right.

tshirt2k i think i think you were right, it may well be sucking in air through the slip joints upstream of the sensor, giving me a false reading. i'm guessing it doesn't take a lot of air getting sucked in to skew the readings substantially? idle is 14:1, part throttle around 16:1, full throttle about 15:1.

what sort of AFRs should i be expecting on a well set-up system with relation to idle, part-throttle, full load etc?

 

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