what is this?
01-25-2009, 01:29 PM
#2
pics?
it might be the air bypass screw which controls air flow through a passage that goes around the flapper door - adjustment for idle mixture. Personally, I wouldn't mess with it, won't gain you anything.
it might be the air bypass screw which controls air flow through a passage that goes around the flapper door - adjustment for idle mixture. Personally, I wouldn't mess with it, won't gain you anything.
01-25-2009, 01:36 PM
#3
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i bought the truck with the motor out of it. and i can tell someone has messed with this screw.
the plugs are starting to worry me as they are very white. with crusty stuff all over them. like its lean.
the plugs are starting to worry me as they are very white. with crusty stuff all over them. like its lean.
01-25-2009, 02:27 PM
#4
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I believe that's suppose to have a metal cap over it; you wont see the screw unless someone has fiddled with it in the past
couldn't tell ya what it's for though
maybe adjust the amount of air that can go through the bypass passage in the AFM?
couldn't tell ya what it's for though
maybe adjust the amount of air that can go through the bypass passage in the AFM?
Last edited by iamsuperbleeder; 01-25-2009 at 02:29 PM.
01-25-2009, 04:43 PM
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umm... idle mixture adjustment- let's the Toyata engineers and parts manufacturers fine tune the mixture "between" the teeth on the gear inside the AFM.
but don't tell anyone I told you that.
and for the record, it only affects the mixture at idle. above idle, there's too much air flowing through the AFM for that adjustment to be significant. Off-idle, the ECU is looking at the O2 sensor for feedback and would override any 'tweak' to that screw anyways.
but don't tell anyone I told you that.
and for the record, it only affects the mixture at idle. above idle, there's too much air flowing through the AFM for that adjustment to be significant. Off-idle, the ECU is looking at the O2 sensor for feedback and would override any 'tweak' to that screw anyways.
Last edited by abecedarian; 01-25-2009 at 04:46 PM.
01-25-2009, 04:47 PM
#7
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umm... idle mixture adjustment- let's the Toyata engineers and parts manufacturers fine tune the mixture "between" the teeth on the gear inside the AFM.
but don't tell anyone I told you that.
and for the record, it only affects the mixture at idle. above idle, there's too much air flowing through the AFM for that adjustment to be significant. Off-idle, the ECU is looking at the O2 sensor for feedback and would override any 'tweak' to that screw anyways.
but don't tell anyone I told you that.
and for the record, it only affects the mixture at idle. above idle, there's too much air flowing through the AFM for that adjustment to be significant. Off-idle, the ECU is looking at the O2 sensor for feedback and would override any 'tweak' to that screw anyways.
I thought that's the flat-head adjustment screw on the TB? or do they kinda serve that same pupose...
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01-25-2009, 04:49 PM
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01-25-2009, 04:54 PM
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ok so what does detonation sound like? it only makes the noise while it cruisin. not on accel or decel. it don't sound like the noise is in the timing chain area. sounds like its in back of motor. and it has 180pounds of compression on all cylinders.
01-25-2009, 04:56 PM
#12
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just don't try to light them on fire; you'll get the opposite of a brain freeze
Yeah, almost 9pm here as well... normally wouldn't be late for me, but I have to get up at 2:30 and make a 3 hour trip down south for business; my first real "business trip" with the company... I feel like a high roller now
their issuing me a laptop when I get down there, putting me in a company truck to make the trip, and a hotel suit to myself for 2 days 
all because the head honcho at our southern Florida branch slacked off, turned the place into hell, and now the head honcho over all of Florida and I get to go down there and straighten the place up 
have you ruled out an exhaust leak?
Last edited by iamsuperbleeder; 01-25-2009 at 04:57 PM.
01-25-2009, 05:07 PM
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You can also get some noise that sounds similar to pinging or an exhaust leak through the PAIR system. My wife just replaced the converter on her 91 and the noise she thought was an exhaust leak went away, presumably because of an increase in backpressure changing how the air flowed through the PAIR manifold.
I'm in Mason, working at the WLW radio facility.
