Bifkin

Greeting all,

Yesterday i took my beloved 1999 RB5 (Not WR) to local MOT station for its annual inspection, i was shocked to find out that it had failed on emissions !!!. I have the full standard exhaust fitted to the car at the moment, a bailey dump valve is the only modification to the engine bay. Here are my results :

Fast Idle test:

Engine Speed: 2500-3000
CO: 2.02 FAIL
HC: 40 PASS
Lambda: 0.94 FAIL

Second fast Idle test:

Engine Speed: 2500-3000
CO: 2.28 FAIL
HC: 85 PASS
Lambda: 0.93 FAIL

Natural Idle test:

CO: 1.49 FAIL

Overall test : FAIL!!!

The car passed everything except emissions. I have ordered a new MAF sensor from my local Subaru dealer at a cost of £67.56 and also enquired the price of a new Lambda sensor £156.00 !!!! (Not ordered yet). I ordered the MAF sensor after reading a thread on teh RB5oc boards. (they are currently down at the mo).

Can anyone reassure me that im heading the right way to fixing this prob or is there more than meets the eye with this type of situation. Any help or advice gladly received.

Many Thanks

Craig.

john banks

Get a univeral lambda sensor on it for about £30.

Shark Man

Woah! that's alot of CO for 2 cats

Looking like an oxygen sensor failure...quite easy to check it - with an analogure voltmetre it should switch voltages every second from around 0.2volts to about 0.8 volts. If it switches any slower its knackered (a digital voltmetre iwon't really work as usually it is not sensitive or fast enough so would probably hover around 0.5 volts, much higher or lower indicates its not right)

£156!! Is that with the labour?? Should cost around £60 or £30 for a geneirc one.

Sure it was all nice and hot..ideally taken for nice gentle blast beforehand? - especially if you've been doddering round like an old fart a few days beforehand

Bifkin

Thanks for your replys,

Could you recommend somewhere i could purchase a cheeper Lambda sensor please id like to get 1 asap i have only 4 days till the old MOT runs out and the car will be off the road =(

Cheers

Craig.

pslewis

The Lambda sensor is the culprit I guess - didn't the garage offer any help?

They MOT all the time I take it?

I know that the Subaru lambda Sensor is very expensive - anyone know why?

MAF gets blamed for anything from a misfire to a flat tyre, from a bulb blown to a wiper split

Pete

zhastaph

You can get a 3 wire universal sensor from Cats Direct, this is a straight swap though you'll have to cut the wires and crimp them to the old connector on the car, it comes with all the bits to do this.

The Lambda sensor is by and large the most likely culprit, they're known to gradually fail and when they do the car will start running rich when off boost.


Other possiblities include;

Dodgy sparks/HT Leads/Coil pack
Poor compression on one or more cylinders
Leaky fuel injector

Though these would result in a noticeable drop in performance also.

Bifkin

Since taking your advice i have:


Stripped out and removed the old lambda sensor (Turbo heat shield was a nightmare to remove heh) and ordered a replacement 3 - wire sensor at a cost of £49.99 + £5 postage, it arrives Tuesday.

I'm still gonna replace the MAF sensor also

Many thanks


Craig.