Honda CR-V Owners Club Forums banner

1st Gen. Idle Air Control and Thermo Valve

2395 Views 11 Replies 2 Participants Last post by  otto888man
Noticed the car would idle a bit low then come back up to regular idle. Hoses are ridiculously hidden. I unbolted the IAC and with teh hose attached just sprayed some Carb cleaner thru the Screened hole (intake side) and the other hole ( output side). It made it worse. Has anyone had success taking it off and pulling that bottom plate and cleaning it better? I have always cleaned these on my other cars without issue. What the heck is the Idle Intake Thermo Valve? has anyone needed to clean that?
  • Like
Reactions: 1
1 - 12 of 12 Posts
Have you tried to clean the idle air passage ?
The air passage? From where to where? I still suspect the IAC since It did get worse after spraying. When I get off the gas, the idle drops way down and then slowly finds it's way close to 500rpm
This screw sets the amount of air to bypass the IAC & sets the base air. If the passages are clogged this is the symptoms you get as what you are having now. What year do you have?

Item # 1. If the passages are clogged the IAC will try to compensate & the idle will go down until the IAC has the chance to adjust the air flow. Use a throttle body cleaner to clean the passages. Remove the screw then spray inside the hole where the screw came out. I believe the screw is brass. The thermo valve is to add more air when the engine is cold.
I get it... I just don't know where it is on my '99. honestly, in 190K miles I have not had to play much other then Timing Belt changes, and Trani and Rear End fluid changes.
Thanks for the THERMO VALVE definition.
No worries. It's good you have replaced the timing belt & other rear end fluids. These vehicles are very reliable. The air passages gets dirty after many miles. Let me know how it turned out.
AIR PASSAGES... Are you talking about some that may be in the Throttle Body Throat? OR?
You mentioned an Air Passage Screw, where is that? It's doing OK, only real issue is that I am out of Valve adjustment on one exhaust valve , Cylinder 3
It’s in the throttle body. I’ll post a diagram when I get home.
It’s originally sealed from the factory when the vehicle is brand new.

item 1
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top