91 22re. on the maf it looks like some kind of adjustment screw. what is that for? thanks

 

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.

 

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.

 

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?

 

on another note, does detonation sound like a loose valve? it sounds like i got one but there are all adjusted right.

 

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.

 

I thought that's the flat-head adjustment screw on the TB? or do they kinda serve that same pupose...

 

idle "fuel" (air/fuel ratio) mixture, not idle "speed".

 

oh, duh, ok, nevermind

wow... total brain fart...

it's late, I'm tired, sorry, lol

 

it's late here too... like almost 9:00 pm.

and have to ask: do brain farts smell?

 

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.

 

their horible...

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?

 

abe you in ohio now? i got a good buddy in akron.

 

detonation sounds somewhat like a few BB's being shaken in a tin can (if you can imagine), random high-pitched 'tinks'.
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.

 

ha ha see i kinda thought this was a small exhaust leak. but today i checked all the bolts and they were tight.