Odd AFR Readings....
#1
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I fitted a Dawes AFR Meter and it seems to be fine, if i boot it through the gears, as soon as it comes on boost i get a blue light
However if i drive fairly hard for a wee while then it seems to get lower and lower until sometimes i only get the red light or maybe orange
If i back off again and take it easy for a minute or two it goes back to normal.. The only thing i could think of is if my fuel pump is on it's way out and couldn't supply sufficient fuel for prolonged periods.... This is my completely uneducated guess so am prepared to be shot down... Only other mods are exhaust, filter and VTA BOV.
Any thoughts/opinions would be apreciated as i don't want to blow it up
However if i drive fairly hard for a wee while then it seems to get lower and lower until sometimes i only get the red light or maybe orange
If i back off again and take it easy for a minute or two it goes back to normal.. The only thing i could think of is if my fuel pump is on it's way out and couldn't supply sufficient fuel for prolonged periods.... This is my completely uneducated guess so am prepared to be shot down... Only other mods are exhaust, filter and VTA BOV.
Any thoughts/opinions would be apreciated as i don't want to blow it up
#4
When driving hard for long periods - high EGTs may be causing the AFR (Lambda Sensor) to under-read - this is quite common & may not necessarily be a problem?
You still need to check everything though - just to make sure.
Chris
EGT gauge &/or Det. Display gauge would help here.
[Edited by Chris.Palmer - 1/18/2003 9:27:50 PM]
You still need to check everything though - just to make sure.
Chris
EGT gauge &/or Det. Display gauge would help here.
[Edited by Chris.Palmer - 1/18/2003 9:27:50 PM]
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As Chris says may not be a problem, lambda sensor sounds tired though. Need to check the MAF to make sure it really isn't lean. You need it on a Select Monitor or similar. Reason I say that is that many cars with a healthy lambda sensor thrashed around a track would still stay on green or blue. Tiring lambda sensors seem to drop off quicker as the EGTs go up.
[Edited by john banks - 1/18/2003 9:21:01 PM]
[Edited by john banks - 1/18/2003 9:21:01 PM]
#7
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Thanks for your help guys.. It is a MY97 with 80k on the clock It is serviced at the regular intervals (every 7.5k) at a Subaru dealer so would they not do this check at the service?
I'll pop round anyway and get them to plug in the select monitor to see if it comes up with anything.
I'll pop round anyway and get them to plug in the select monitor to see if it comes up with anything.
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#8
Had this very same problem a few weeks ago posted a few threads on here if you do a search for lambda sensor or AFR heading.
The fault never showed up on computer when I took car to Main dealers.
Went ahead and bought a new Lambda sensor, fitted it took about 5 mins, Bobs yer uncle, works fine now Blue light constantly at WOT.
The fault never showed up on computer when I took car to Main dealers.
Went ahead and bought a new Lambda sensor, fitted it took about 5 mins, Bobs yer uncle, works fine now Blue light constantly at WOT.
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Just been thinking (scary isn't it) I'm sure i read somewhere that that when you're on WOT the MAF takes over for the fuelling as opposed to the Lambda sensor The Lambda is only used when it's not on WOT... In which case it couldn't be a faulty Lambda causing my probs
Or have i got it the wrong way round
Or have i got it the wrong way round
#14
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Seems to be a pretty common fault this one
I too have a 94WRX which is showing exactly the same symptoms, but i have an Autometer AFR. I was actually beleiving that the gauge was shot.....
New lambda sensor on order as we speak
I too have a 94WRX which is showing exactly the same symptoms, but i have an Autometer AFR. I was actually beleiving that the gauge was shot.....
New lambda sensor on order as we speak
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