A mate of mine is getting seriously low milage from his motor and i want to check if his lambda is behaving normally or not.
What voltage should i be expecting from the lambda sensor at idle and am i correct in thinking it should be reading around 0.9v at WOT?
Also can someone confirm that the ecu pin out for a MY99 lambda reading is "B136 #7"

Any advise appreciated.
Cheers, John

 

Problem is that during closed loop (ECU control) fuelling, the ecu will continue throwing in fuel until it reaches the voltage it thinks is stoich from the lambda. That's why it uses so much fuel

And on WOT the voltage is not really to be relied upon as many factors affect it's operation (stock should be above .985v on the first power run, but will progressively drop afterwards).

I'd recommend swapping the lambda from a known good car to confirm....unless, like a lot of phase 2's, the sensor was overtightened in the factory and a pig to remove

Richard

 

I know when mine went knackered it was stuck on a reading of about 0.26v so i will see what i get on his.
Cheers for your input dowser.
Just need to confirm the pin out.

 

Pin required is B136-21, can email a pdf if you need it.

cheers

bob

 

Nice one Bob, if you could e-mail it me that would be great.

[Edited by Triple X - 10/31/2003 11:43:38 AM]

 

Actually just found the pin your refering to in the Link users manual. The pin number i gave above was from Ravens Blade web site for an MY99 RS ecu pin out diagram. Is the RS ecu pin out completely differant? I take it it must be as it seems to show 2 oxygen sensors.
And also is an STi V5 ecu the same as a UK MY99?

[Edited by Triple X - 10/31/2003 1:06:16 PM]

 

The v5 Sti is similar, but crank and cam sensor pins are swapped, plus STi may have intake temp sensor.

Richard

 

Ive just replaced my O2 sensor with the Halfords L300. Ive suspected my O2 to be out for a while, anyway i fitted an AFR meter, and it wouldnt work, so indicating failure of the O2sensor. Sure enough, as soon as the new O2 sensor was fitted the AFR srung to life.

and guess what..?? my fuel economy raised from 260km's on a full tank to 340 ... blimey, if only i had of realised 6 months earlier.

 

incidentally, my O2 sensor was stuck reading 0.280v when i checked it before removing it.



MY93wrx

 

Link manual is a direct crib of the Subaru manual and is correct, it also covers the switched crank/cam sensor inputs.

cheers

bob

 

Good stuff, thanx for your help guys.