HAI Valve Test / Repair / Replace Questions

[brownfj60]

Working on my 85 wagon final stages of putting back together after cracked head. I am reconnecting air intake hose and hot air intake hoses long ago removed by the PO. I decided to test the function of the HAI valve by applying vacuum. My HAI valve will actuate momentarily when I apply vacuum, but leaks back in less than a second and the flapper returns to cold air intake. I don't see a specific test for this valve operation in the emissions FSM, but I'm thinking that this behavior would introduce a vacuum leak when the HIC valve sends vacuum to the HAI valve.

Planning to open up the HAI valve and inspect for a leak in the diaphragm unless anyone here can tell me that the HAI valve should leak when vacuum is applied.

Thanks, Jay

 

[Shacklewhacker]

Are you saying the HAI diaphragm that controls the air control valve in the intake will not hold vacuum?
There is a test for the HIC valve using hot water as outlined in the emissions manual. But if you are saying when you apply vacuum to the HAI diaphragm directly, it will not hold in the positions to direct the hot exhaust air into the intake, then yes - the diaphragm is bad. There is not means to repair it either - it must be replaced.

 

[brownfj60]

Are you saying the HAI diaphragm that controls the air control valve in the intake will not hold vacuum?

Yep, HAI valve won't hold vacuum. Thanks for confirming, will try to find one to replace.

 

[Shacklewhacker]

Yep, HAI valve won't hold vacuum. Thanks for confirming, will try to find one to replace.

SOR has them for around 30-40 bucks used.
You could ping some folks here as well - someone may have a good one avaialbe