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mattysr20
05-03-2013, 02:35 PM
ok I made one thread about this and I saw the other guys thread about his readings. If a mod wants to delete my other thread that's cool I'm just making this one to try and clean things up a little so I hope people don't get mad I'm just frustrated and wanna figure this out cause the shop can't get me in till next week some time......

so anyways for starters
95 240 ax
s15 Sr20det
normal mods
turbo mani
Megan down pipe
3" cat back exhaust
stainless lines
Megan fpr
circuit sport grounding kit
turboxs bov
turboxs mbc
autometer wideband
HD fmic
Jim wolf tuned ecu
444 injectors
z32 maf
walbro inline fuel pump
12 gallon fuel cell in trunk

ok my issue is my wideband gives crazy reading all the time.
when its cold or cool out it stays at 14.7-15.0 sometimes going a little rich if I get into boost . but when its hot out it goes crazy even when not boosting at all it jumps from 15.0-10.0 and back up to 15.0-14.7 then jump around in between.
I've tried a few things but nothing helps at wot sometimes its rich and other times its lean so I can never tell what my exact reading is.
I do know my bov was leaking and might still be even though I put washers in also I'm pretty sure my fuel pump is going out cause it been acting and sounding funny lately. Is their something I could try? its driving me nut cause I don't want my car to be F-ed up.... I have a video of the wideband reading while driving I just don't know how to post it but I could email if someone wants to see it..




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mattysr20
05-06-2013, 04:13 PM
bump still need help


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mattysr20
05-07-2013, 10:39 AM
why does it only happen when hot out? last night it read perfect last night when it was cool out. It doesn't make sence


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Beemer
05-07-2013, 07:51 PM
How is the sensor in the exhaust installed? Maybe to far away or maybe its not installed on the right angle and is getting moisture on it.

mattysr20
05-07-2013, 09:11 PM
ite on the top of the down pipe bout 3-4 inches from turbo


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Beemer
05-07-2013, 09:40 PM
hmm i dont know if the auto meter wideband is any different then the aem ugeo one, but aem recommends 36 inches away from the turbo. I dont know if that will make a difference or not.

codyace
05-07-2013, 09:44 PM
What does it read when WOT?

OnTheChip
05-08-2013, 09:28 AM
Sounds like an exhaust leak that gets worse as things warm up.

Dave

mattysr20
05-09-2013, 09:28 AM
its usually going nuts but when good at wot it goes into 12s then other times it reads in 14s


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jsu1012
05-09-2013, 09:34 AM
Sounds like an exhaust leak that gets worse as things warm up.

Dave

That's what i was thinking too.

OnTheChip
05-09-2013, 09:44 AM
Other possibilities:

Intermittent fuel pump
non-recirculated/leaky bov
Intermittent MAF signal
Vacuum/boost leak

jovan344
05-09-2013, 10:19 AM
email me the video [email protected] it could be that you might have to alter the fuel tables in between rpms, is it in closed loop or open loop ? and does the afr jump around when youre on a constant speed like constantly on 3k rpm or so ? if you rook it to a dyno and they only did a power tune you still need to do your low speed fuel tables dyno tuners are lazy and only really mess with high speed fuel tables, I make my own street tunes, e to make the car run as smooth and light possible when cruising and actually feel the car pulling each and every bit as I accelerate

ultimateirving
05-09-2013, 11:42 AM
Having the 02 sensor so close to the turbo is not recommended. It should be downstream a little further. If your plugging it into the factory 02 housing your doing it wrong.

Croustibat
05-09-2013, 11:51 AM
Having the 02 sensor so close to the turbo is not recommended. It should be downstream a little further. If your plugging it into the factory 02 housing your doing it wrong.

It works very well at that place, it only shortens the sensor lifetime as it gets hotter. Nothing a little radiator cant fix.

stuckonfresh
05-09-2013, 01:33 PM
you could try AEM's sensor test to see if the sensor is still good. Basically you just have the sensor out of the exhaust but hooked up then turn the key to the on position, but DONT start the car! Afs should read super lean, be careful too bc the sensor gets hot. Then dampen a paper towel with brake cleaner and put it around the sensor- the Afs should go towards the max rich. If they fluctuate the sensor is most likely the problem.

Could look up the vid on youtube too, its by AEM and steph demonstrates it