2009 GX470 - What is normal idle spec? My idle swings from 700 to 500 back to 700

[JimFromAZ]

Hi All,
What is the expected idle on a warmed up 2009 GX470?

I purchased my GX two months ago and I'm going through all preventive maintenance items (all fluids changed, greased fittings, check torque on drive shaft bolts, replace leaking valve cover gaskets or at least torque loose bolts to proper torque, replace dented trans pan, etc). This is a great process to learn about the vehicle!

When warmed up, I noticed that my idle, when waiting at a traffic light, is around 700 but then cycles down to 500 for a few seconds then back to 700 and repeats. 700 seems smooth, 500 is more rough (I can feel it). This happens whether A/C is on or off (I'm in Arizona so it's usually on). I've cleaned the MAF sensor and air intake and replaced the air filter. Now I'm searching for hard, brittle or cracked vacuum hoses and will swap those out one at a time as i find them. Is this idle cycling normal? Is this a common problem with GX470's? Are there any specific parts I should inspect or replace to eliminate this cycling idle? It kinda drives me nuts!

Thanks Everyone! The members of this Forum are tremendously appreciated!

Jim

 

[Green4Gulf]

Late to the party, but was an answer found?

 

[micah4wheeler]

Hi All,
What is the expected idle on a warmed up 2009 GX470?

I purchased my GX two months ago and I'm going through all preventive maintenance items (all fluids changed, greased fittings, check torque on drive shaft bolts, replace leaking valve cover gaskets or at least torque loose bolts to proper torque, replace dented trans pan, etc). This is a great process to learn about the vehicle!

When warmed up, I noticed that my idle, when waiting at a traffic light, is around 700 but then cycles down to 500 for a few seconds then back to 700 and repeats. 700 seems smooth, 500 is more rough (I can feel it). This happens whether A/C is on or off (I'm in Arizona so it's usually on). I've cleaned the MAF sensor and air intake and replaced the air filter. Now I'm searching for hard, brittle or cracked vacuum hoses and will swap those out one at a time as i find them. Is this idle cycling normal? Is this a common problem with GX470's? Are there any specific parts I should inspect or replace to eliminate this cycling idle? It kinda drives me nuts!

Thanks Everyone! The members of this Forum are tremendously appreciated!

Jim

Have you cleaned the throttle body? You mention air intake, not sure if this is what you mean.

 

[Green4Gulf]

It's not the TB, but the a/c compressor kicking on when my defroster is going. I had never noticed it, so it made me a little paranoid. When my defroster is off, there is no idle surge, and everything runs smoothly. Still, I went to the parts store, got some TB cleaner, and will hopefully be cleaning next weekend.