help me out with air fuel ratio
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I have just installed a afx air fuel ratio meter in my car(402 and full bolt on's, fast 102 intake and t/b...), i am waiting to tune with hp tuners(not received yet) and help from a tuner by e-mail. just wondering what a/f should i see while crusing around and also idling, just something for me to keep an eye on while i wait. i left it idle last night and my a/f was 14.6 and drive home from shop(1 mile) 14.5 at low rpm and i looked under car and my cats were turning red after i had left it idle???
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Have you driven the car before the addition of the a/f gauge??
Did you do a free air calibrate on the sensor? [I'm assuming it's a wideband??]
Are you SURE it's working?
No change in idle vs driving sounds like it's not.
Over heated cats will cause them to fail....FAST!
What do the oem sensors read?
Sounds like the a/f is WAY off.
Did you do a free air calibrate on the sensor? [I'm assuming it's a wideband??]
Are you SURE it's working?
No change in idle vs driving sounds like it's not.
Over heated cats will cause them to fail....FAST!
What do the oem sensors read?
Sounds like the a/f is WAY off.
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i haven't driven car since installing fast intake 102 and t/b 102, same size but different brand injectors, my tune was off before them changes, that is why i did modes because i knew i was getting it tuned again, yes i calibrated the wide band,ntk, there was changes in air fuel ratio but that was the average i was seeing, i only drove a mile., i also have a 100mm maf but had my old 85mm on car to get it to the shop, it won't even run with the 100mm.
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uummm.. not understanding this here. The car, under all part throttle & cruising will be at Stoichiometric...14.6 or so AFR
your cats shouldn't be glowing red just from this and from idling. have you gotten your eyes checked?
if you didn't go WOT...or beat the **** out of it, none of your exhaust should be glowing at all.
your cats shouldn't be glowing red just from this and from idling. have you gotten your eyes checked?
if you didn't go WOT...or beat the **** out of it, none of your exhaust should be glowing at all.
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i know that they should not be red, i drove from shop slowly, no hard aceleration 1 mile and left idle while i open the door of garage , i could smell like burnt plastic(the same smell i have been smelling at my last tuner all summer long, i went there 8 times for retune, every time he would leave it idle for long period of time i would have the same smell, only the back part(exit) of the cats were turning red. can i get someone to give the normal a/f for differente conditions like idle, crusing,acceleration etc, i kno every car is diferent but just looking for refrence.
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(8 times) that is why i getting hp tuner and i am going to work with a professionel tuner by e-mail, my first guy was a 7 hours round trip every time, my next closest is 32 hours round trip, you said 14s are fine, what about acceleration?
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as i am doing more research on a/f ratio, my tuner last year had the sensor clamped on the tip of my exauste maybe 3 inches in, and also i still had my air pump instaled on my headders and my 2 cats, isn't this all wrong, shouldn't that a/f sensor be ahead of the cats (isn't cats capable of storing oxygene)and no air pump putting more oxygene in the systeme, wouldn't that give him falls reading?
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From what I understand the reading in the tailpipe will be a couple tenths leaner after cats, etc. So, if you trying for stoich (14.7) you would want to see about 14.9-15.0 at the exit.
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what about being so close to exit of tail pipe, also having the air pump still on car would make a difference, when does the air injection pump air in the exauste anyway?