I fitted my Dawes AFR this week (the one for Impreza's) and found that it didn't light up under any circumstances, except once it flashed amber for about half a second.

I rechecked all my wiring changed my power feed so that now I'm coming directly off the battery (2 amp fuse), earthed to the battery and I'm tapping into the white lambda wire at the ECU.

Sound like a knackered lambda sensor maybe?

 

Could be, but there are probably more likely explanations.

If your O2 sensor was completely knackered, you should probably expect a CEL, rough running/poor fuel economy off boost, or both. Is this the case?

Also, are you certain you got the right wire in the ECU plug, that the fuse is good, and that the AFR meter itself isn't faulty?

If in doubt I'd try and check the lambda output at the ECU plug with a digital voltmeter to make sure there's something coming out.

 

No CEL, car runs great, get about 21 - 23 mpg as an average.

Fuse is checked, as was all wiring (I actually re-did it all this afternoon as it wasn't as tidy as I would have liked).

I'll check the readings on the lambda signal and also try connecting the AFR up to 12v which should light the blue LED (according the their website).

 

Yep, it's definately white with a silver stripe

 

your lambda sensor is knackered. Mine was the same when fitted.... ran fine....No CEL. Changed the sensor, and worked fine. As a result though I got the MY99/00 cold hesitation thing

 

STi, when you say "as a result" do you mean after you changed the sensor or before (i.e. as a result of the knackered sensor) ? My car runs like a dog when cold.

 

Rev, now mate.

I have fitted two of these afr's to two diferent Leg T's.

On my car I spent hours taking the thing on and off coss I could get it to light up. It turned out that I didnt allow the sensor time to heat up and start working. . I went out for a run and with in ten minutes hey presto christmas lights.

Not saying thats the problem, but have you been out in the car since wiring it up? My wiring was right first time. doh.

Me mates car was a bit different again. Could I cobblers get the afr to light up. He got the odd flicker of the amber light but it wasnt working in sequence.

A new lambda sensor from Subaru sorted that out though. Both cars now opperate correctly and doing what god inteded.

Might be of use .... prolly not but you never know.

Good Luck.

Ste.

Oh and cant remeber if I thanked you for the Bosch coils?

If I didnt....... THANKS .... Your a star.

 

Cheers STE

I thought about that, I'd let the car run for a few minutes on the drive, then went out for a 5 minute run and no lights. Then I had to take a run out to Manchester Airport (half an hour each way) and still no lights

I think I'm going to bodge one of them Halfords £20 jobbies on and see if that makes a difference.

 

With the new sensor I got the hesitation.

 

OK, how the *&^% do you get the old sensor out? Soaked in WD40, lying with my feet wedged on bits of the suspension and pulling with everything I have and the bugger won't move. Tried the hammer (well pissed off by this stage) and all that does is round the nut off.

I remember a thread a while back saying that it's easier to do this while the engine is stone cold (i.e. left over night) but is that right? Thinking I might warm it up a bit so then I'll be soaked in WD40, lying with my feet wedged on bits of suspension and suffering 3rd degree burns. [img]images/smilies/mad.gif[/img]

Ban cars, I say! [img]images/smilies/mad.gif[/img] [img]images/smilies/mad.gif[/img]

 

Woohoo, sorted, lights now work as expected, although the car doesn't seem to run any differently

ECU reset on the way!

 

Eh? What were you expecting? AFR meter isn't supposed to make your car run any differently, it just tells you how it's fuelling.

 

greasemonkey

He means the new sensor he has put on..!

Dan

 

Yep, thats exactly what I meant.

With the new sensor fitted, car spends most of it's (full throttle) time lighting the blue, with the occasional green flicker, although I do get a momentary red light going from cruise to WOT, but I guess thats normal and it quickly goes down the scale to blue.

 

Doh, I've woken up now!

Sounds like you're now seeing what you'd expect to see from a properly functioning engine and sensor.

Not too surprising that you don't feel any difference, especially when you're giving it some welly. Don't forget that as soon as the engine goes open loop, the ECU ignores the lambda reading and fuels based on MAF. Thus, even a totally knackered lambda sensor wouldn't affect the car when driven hard.

You'd be most likely to notice any differences when just cruising around. Improvement in fuel economy would be the likeliest "symptom" of the sensor replacement.

[Edited by greasemonkey - 9/13/2003 6:00:55 PM]

 

Every time I buy something for the car MrsREV says "will that make it more economical?". At last, I don't have to lie!

 

Try the same trick with a bigger turbo. If it lets more air into the engine, the car will go further for the same amount of fuel!

 

 

Got my dumb head on - WTF does "WOT" stand for

 

Wide open throttle

 

Ah, my right foot syndrome

 

NotoriousREV,

When you took the pin at the ECU i.e pin 6 B43, did you count 6 wires across because if you did you may have the wrong wire. If you look closely at the B43 plug one of the positions were a wire should be is blank. I think the wire you want is white with silver stripes around it..

Dan


[Edited by dhorwich - 9/11/2003 7:00:00 PM]