4age very low idle on a hot day???

[old ae92]

4age very low idle on a hot day?
hey
On the hot days we have recently in syd when im driving my my 4age rolla fwd i hit a red lights i slow down of course when i do the revs drop quick.
when i stop they drop to about 400 rpm there bouts and that drop nearly stalls the motor then it just sits near 500ish rpm on a hot day but on a cool day it runs fine between 800rpm and 900rpm i dont want to forget about the problem so im asking for help on this
is it an intake thing due to humidity in air as i have a stainless mesh pod filter the only mod i have
cheers mike

[roadsailing]

if you have aircon, do you use it on hot days?

thermo fans can drop your idle quite a bit, mine does, but my idle is all over the place anyway, due to not having any idle bypasses at all.

[toyoda]

this seems 2 be very common. on hot days or after giving my rears a good work out my rpm will do the same...
i have a thermo fan so it might be that like shinybluesteel said.

jay was asking about this the aother day. jay n e answer?

[old ae92]

i do have air con but cant use it due to missing parts near radiator think its the a condenser and pipe work.
im not sure whether the termo is running a the time but if its hot i suppose it would be running

[beige_bandit]

my 4age does the same but i have no A/C and no thermo fan!

My theory is:

Air is less dense when its hot or humid, so your idle is set when air
is at an average temp(hopefully in this case) , then you get out there on a hot day
and idle drops cause of the less dense air?

just a thought, but on these hot past few weeks my idle has been changing
from morning to afternoon.

[Goolz]

Your idle drops because on all 4age's they have coolant running through the throttle which in turn heats a wax pellet making it softer which then is used to raises or lowers your idle. Its toyota's way of making a cold start. On really cold days your engine will start at 2000rpm because the wax pellet is solid and lower down after it softens it up. Its just in summer the extra heat causes the idle to go lower than the 900rpm standard.

[WiLo]

is your pod in any sort of enclosure? if not it may be sucking the hot air from under the bonnet

[beige_bandit]

Your idle drops because on all 4age's they have coolant running through the throttle which in turn heats a wax pellet making it softer which then is used to raises or lowers your idle. Its toyota's way of making a cold start. On really cold days your engine will start at 2000rpm because the wax pellet is solid and lower down after it softens it up. Its just in summer the extra heat causes the idle to go lower than the 900rpm standard.

Umm , 4age's actually have a cold start injector on the plenumb
And he is talking about hot days not when the engine gets hot