1999 V6 SOHC p0174 p0171 "sneeze sound" and rough idle

[Bcarp100]

I have searched and trouble shot as much as I can now I need help! I have replaced the MAS, cleaned the ICV, checked for leaks, replaced the lower and upper intake manifold gaskets with no luck. After replacing the gaskets I have acquired a strange "sneeze sound" as well as a whistle only while the car is in drive. My next plan of attack is to replace the ICV. I have also replaced the fuel filter and and air filter. This car only has 57,000 miles on it I need some serious help!!! Anyone with experience or ideas on what is going on would be greatly appreciated! Thanks!

 

[2000StreetRod]

IAC valve gasket?

Check the condition of the intake air control valve gasket. It's a very thin gasket shaped like a figure 8. It is easily damaged when removing the IAC valve for cleaning.

This thread may give you some ideas: Lean condition procedure

 

[Bcarp100]

Ok will do what about the green one underneath it what is that called so I can get it ordered?

Just wanted to update that I replaced the gaskets for the IAC valve and I am no longer having any problems. It is running great!