O2 sensor

[Fast Guy]

Is this worth changing for the just sake of it, now that most of them will be very old. ie will we see any benefits? It tends to be one of those parts that sit's there and gets forgotten about and to be honest I don't know how long they're supposed to last.

Is there a suitable (cheap) replacement part or are we stuck with OE Nissan. (anyone got a price)

 

[deslynam]

Just get it checked to make sure it's switching correctly - mine wasn't but it was due to dodgy connector rather than the sensor itself

 

[Trust-R]

there are replacements available and cheaper but aslong as the sensor is working no need to bother with it, and its definately one of the things that nobody thinks about, regarding how long theyre supposed to last no idea , i guess a very long time though

 

[Sunny GTi]

Your right Fast Guy, lambda's do tend to be neglected. Tbh, mine still works fine so Im in no hurry to replace it, but after so many years of soaking up exhaust fumes they can get poisoned and getting a new one wouldnt be a bad idea.

If a sensor is past it, it can throw off the emissions and possibly fail you an MOT, lead to hesitation when pulling through the rev range and also make idling irratic.

I cant say for certain about the 'R, but the GTi uses a 3-wire Titania sensor. Not very common so its not cheap and expensive from Nissan I should imagine. Best places Ive found are http://www.justlambda.co.uk/ and http://www.rinis-automotive.com/product.php?xProd=96&xSec=1183

 

[chrism]

I checked,its 180 quid from nissan!!

 

[campbellju]

I thought my Nissan one was the right side of £100, possibly £80? As someone has said, they're Titania so even the non Nissan ones will be expensive. Zirconia ones won't work. The main improvement will be in idle and cruise economy as that's the only time its used. I changed mine after an MOT fail but my economy did improve as a result too.

Jim

 

[Sunny GTi]

Actually, the lambda sensor constantly sends an electrical signal to the ECU, not just when the engine is idling or cruising. Thats why a sensor that has deteriorated can cause an engine to run poorly under any conditions.

 

[campbellju]

Yep, you're right. I should have said, that's the only time its of any use. I'm not convinced about the self learning mode as it never seemed to correct for minor faults. I don't know if you know what modification range it has?

 

[Sunny GTi]

Of the ECU? No idea tbh, not sure if being quite old it would even have that capability.

Evo's and presumably other modern cars have built in knock sensors so can advance ignition automatically if the petrol quality allows. Oh and apparently if you unplug an R34's computer overnight and then reconnect it the next day, it can adapt to things like filter and exhaust upgrades and set itself up automatically!

 

[ashills]

pulsar uses knock signal to push ignition where possible thats why u have limp home mode etc and code 34 when the knock sensor is knackered

 

[Fusion Ed]

The ECU doesn't learn as such. I.e. It cannot re-map itself, by slowly learning a map correction table or anything. Instead it has one main correction which is the AFR Base correction, this is the trim table that its adjusted by the lambda feedback, and it compensates the main fuel map to ensure that the ecu is providing correct fuel when in a closed loop condition and it will also use this for when in an open loop but at the last closed loop value. (as far as i know anyway)

The ecu also has two ignition maps. A high octane for when no knock is present, a knock map with retarded values for when knock is detected and if there is still knock detected / or a fault with the sensor, it will then go into fault and show the knock error code.

These ECU's do not trim the ignition such as some more modern ignition systems can.