mr2 engine idle issue

[L~tw]

sw20 turbo 1990
Dring the driving time, I turned the A/C on for about 30 min. When I park my car on the garage I found the engine idle dropped to 500rpm... On the next day, it's back to normal 950 rpm. I've no idea what's wrong with that??
Need help
Thanks

[Silent Knight]

Has it done this only once or does it happen really regularly?
Any other side-effects whilst driving or only as you say when it's in neutral after you have driven it?

[L~tw]

Has it done this only once or does it happen really regularly?
Any other side-effects whilst driving or only as you say when it's in neutral after you have driven it?

it's happened regularly when I switch A/C on. If I dont switch on the A/C that's wont happen.

[dragonx]

maybe the a/c idle up is not working
and maybe the a/c idle down is working

so when you use the a/c idle does not increase that little bit, but when you turn it off idle down still works.

i made that up though, sounds reasonable to me though.

[fivebob]

maybe the a/c idle up is not working
and maybe the a/c idle down is working

so when you use the a/c idle does not increase that little bit, but when you turn it off idle down still works.

i made that up though, sounds reasonable to me though.

They're one in the same, idle goes down because of the load of the A/C, but the aircon computer opens up the idle VSV (which is located on the rear firewall) to increase the idle.

You're right though, sounds like it's not opening or is clogged up.