up and down idle

[GlanzaV]

hello guy i had a problem with my glanza its idleing up and down olny when its hot ???
ive clean the thottle body out and the icv out and check ecu and no codes.
HELP !!!!!!!!

 

[lukep]

I had this it turned out to be a split vacuum pipe

 

[Stu-]

Usually if its pulsing up and down then its due to the water lines through the throttle body being restricted or blocked - when you cleaned out the throttle body did you take the bottom off and clean out the water lines? Worth a go.

 

[RichielightweightGT]

i was in toyota yesterday and was told they can suffer from hunting over this or an airlock is there anything in particular you could use to clean it as my gt suffers from this also and i have changed my icv nd chech that my pcv is not blocked also

 

[Rev]

The suggestions above are good -
But remember when its hot the fans go on, I have a two , two stage fans , the revs drop 100 firstly then another 200 when the fans are flat out.
This causes the spark to be reduced and the car shakes.

As a work around I have rasied the out of gear idle to 1300 from 900 and putting a new earth on the block to drivers side chassis of the car.
I now have more power and acceleration than before.

But the idle up still does not seem to work properly when the a/c is on , when turning the steering and when stationary, as the additional A/C load causes the idle to drop.

 

[TheStarletGT]

Your alternator is rooted. Dont belive me, check the voltage across the battery. It will stay at 12.00 volts at idle and revs. I had this issue just recently, it would rev than idle, rev than idle. VERY consistently.