Heating / AC system

[Mad_Trbo]

Ah my family, I tell you as many times as I come here for information. I am definitely going to have to call the folks here my surrogate(sp) family.

Fam - I recently traded out my old cracked dashboard for a new one and as one might imagine this job required the removal of the AC / heat fan controller. On the switch that moves from AC / heat / defrost etc... I notice a connector with several vacum lines to it. Since making the switch I have noticed a slight hissing coming from this direction in addition to the hissing it appears air will only blow through the defrost.


1st question is this hissing obviously sounds like a vacum leak will that effect the motor or is there a check valve.

2nd is this hissing more than likely disabling my ability to control where the air blows (ie vents / floor / defrost )

Ok 3 questions, is there an easy fix, possibly plugged in wrong?

Thanks

 

[my85grandnation]

I just got done changing my my dash over a few months ago. Mine didnt hiss, but at frist I could only get air out of my heat ducts/defroster even when I had the control on vent. I switched to A/C and let it run for a while and finally it started to come out of the dash vents like it was supposed to, and its worked fine since then.

 

[Mad_Trbo]

I'll keep working with it and see if it corrects itself. The motor itself does not seem to be suffering from the ill effects of a vacum leak. I'll assume the hissing I hear although probably a vacum leak is not directly connected to the motor.

 

[TURBOTWIN2]

A/c

The hissing IS a vacuum leak coming directly from your engine. Re-check your connection at the A/C control head, it probably came off or didn't make a total connection. The default vent control goes to defrost with no or insufficient vacuum to that control pod. Go back where you already where working. We call that a "comeback" in the repair trade. HTH.

 

[Tampa T-Type]

Mine did the same thing!

You can get a replacment vacuum switch from the dealer. They get loose on the top, it controls all the routing for the def, heat ect.

 

[Mad_Trbo]

Hah on the comeback, I spend more time coming back than I do moving forward these days.

Tampa T-Type, You replaced the switch or the connector, seems more likely the connector would go out and not create the proper seal.

Did this repair your problem

 

[Mad_Trbo]

Dyno on an Automatic

How do you do a dyno pull on these cars. With my Eclipse all was done in 3rd gear which created a constant.

With an automatic it seems difficult to get an accurate dyno reading with the shifting. Can someone give me a 2cent education?