No air in the right vent

[Joe C]

I have a 96 LT1 and Im scratching my head because I cant get cold air to blow from the forward vents. I have changed the A/C programmer, I have changed a 7/32 vac line that runs from under the dash thru the firewall and into a canister/pump close to the battery. I have checked the vac lines that run under the passenger side fuel rail and they are fine. I have noticed a rotten vac line at a module that is behind the drivers head light, I will change that out tomorrow. As of now I have cold air blowing from the defrost vents and at my feet, none from the dash....what am i missing ???

[c4c5specialist]

Hi there,

Nothing that I can see.

Vacuum controls it all so you have to have some type of vacuum leak.

Allthebest, c4c5

[Joe C]

ok....tell me stranger things have happened. I replaced every vac line under the hood and still no air from the dash vent. I was checking that small tank behind the drivers headlight and i didnt plug in the power/sensor cable then all of a sudden i had air flow from the dash vents...plugged it back in ..no air!!! as it stands now, i have that plug wire unattatched and cold coming from the dash...

[Joe C]

I drove the car this evening and my issue appears to be semi solved...Upon start up I get a strong flow of air from the defrost and at my feet. After about 5-10 minutes the cold air finally makes it to the dash vents but Im still getting a little bit of cold air from from the defrost...its about 20% from the defrost and 80 % from the dash...any ideas ?????

Thanks in advance

[c4c5specialist]

Hi there,

You still have some type of vacuum leak. Its not developing enough to fully change modes.

Allthebest, c4c5