IDLE ADJUSTMENT

[Toyboy]

Just thought id ask yous guys if you had adjusted your idle b4 :?: I in the past have adjusted it using this screw here
http://www.digitalpose.com/mbr/1/13511/p/485560_7521823962538681445_vl.jpg
But have been told by another person i should be doing it through this screw here in the throttle body

http://www.digitalpose.com/mbr/1/13511/p/485561_5262578596351894493_vl.jpg

Which is the correct 1 for the adjustment :?:

Thanks in advance :wink:

[BigBoyLemonade]

the 2nd way...

[Toyboy]

Thanks Tony,had a feeling that was the proper way,but i never knew so i did it the other way :oops:

[Aaron]

In a way they're both right....

The top one is adjusting the 'base position of the throttle butterfly... The 2nd pic is adjusting the airflow through a bypass port on the throttle body.

The 2nd one is for fine adjustment to get a 'base' central idle point that the ECU can then control via the IAC motor (which is why the car has different idle speeds depending on the A/C, electrical load, engine temp etc etc.

Ideally the blade should be adjusted to a fully closed position but not 'wedged' and the idle set via the bypass.

A.

[Toyboy]

Should the idle be set by this screw(bypass port) while the diagnostics are in test mode? And what exactly do you mean by "wedged" :oops:
Thanks for that Aaron :D

[Aaron]

At a guess I'd say yes it should be in diagnostics or 'calirabtion' mode or whatever mode Mazda has to allow for it to be adjusted properly... Normally such a mode sets the AIC to dead middle of it's normal range meaning that it can adjust equally on each side of the set idle.

However I don't have the Mazda books, so this is probably best left to someone with the appropriate FSM.

As for wedged, this depends on the TB design, most aren't made up of a perfectly round throttle plate, rather it's ovoid and is set to be closed while still being at a slight angle. This means that it will 'wedge' if the spring pulls it back past a very light touching fit. The vibration and pressure will eventually wear grooves into the bores of the TB and then you've got stuff all chance of ever making it idle right again unless you resort to tuning trick 101... Boring the TB ;) To adjust it right typically you'd back the screw out until it's 'free' of the stop point, then wind it back so it's 'firmly' against the stop point and maybe a little past it. It varies from car to car though. Some want it cracked open a bit and then a fine adjust done with the bypass before leaving the whole lot up to the ECU and IAC.

I definately don't know enough specifics about the Mazda setups but would think that the FSM has it all covered.

BTW has anyone got one of the digital dash interfaces runing on their car?

A.

A.

[Toyboy]

Thanks again Aaron,your input is appricated :D

[dfvadr]

possibly if ur idle needs doing all off a sudden
the throttle body may need cleaning so get sum carby cleaner take off the intake pipe give the throttle body inside a good spray clean start the car
will run like **** for a couple off seconds while it clears should make the accelerator easyier too
cheers

[Dogo]

*drags up an old topic*

I want to adjust my idle on the weekend, and I can see these 2 adjustment screws. But having never done it before can someone give me an idea of what i need to do ? The car seems to rev a bit high at idle.

It also drops low if the clutch is pushed in suddenly and it looks like it could threaten to stall if i dont do something abt that too

[Toyboy]

If you turn that screw in clockwize dogo it should drop the idle,anti clockwize will raise it,thats all i can tell ya :wink: