• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Air vents not blowing when accelerating

J

jvluntzel

Member
Joined
Mar 1, 2018
Hi All!

trying to figure this one out. When I accelerate or hold throttle going up a hill, my air vents inside stop blowing air. I am assuming this has something to due to the fact that the engine is in a 0 vacuum state and some actuator is moving when it shouldnt or vice versa.

Any direction on this is greatly appreciated!
 
iirc there is a one way check valve (black and white) on that hose from the IM that prevents such a thing.

However, you didn't list which vehicle this is and I believe your assessment may be inaccurate or mis-stated but to be clear... your vents are closing off via vac yes? Your blower motor doesn't actually stop running correct? If so, then check that valve.
 
Vacuum actuator for vent has a torn diaphragm. Common problem. Only source is the junkyard. Sometimes new/nos one pop up on ebay.
 
EivlEvo said:
iirc there is a one way check valve (black and white) on that hose from the IM that prevents such a thing.

However, you didn't list which vehicle this is and I believe your assessment may be inaccurate or mis-stated but to be clear... your vents are closing off via vac yes? Your blower motor doesn't actually stop running correct? If so, then check that valve.
Click to expand...

Easy way is to unplug it (optionally, attach a bit of clean hose) and blow air in each end. If air passes in both directions it's fukt.

If ithe check valve is working, then you have a leak somewhere else in your under-dash vacuum system. Good luck!
 
ZVOLV said:
Drive backwards.
Click to expand...

this is genius. I love it

Ursan said:
Don't forget to mention, (as always) year make and model.
Click to expand...

91 volvo 740 wagon non turbo REX

EivlEvo said:
iirc there is a one way check valve (black and white) on that hose from the IM that prevents such a thing.

However, you didn't list which vehicle this is and I believe your assessment may be inaccurate or mis-stated but to be clear... your vents are closing off via vac yes? Your blower motor doesn't actually stop running correct? If so, then check that valve.
Click to expand...

Pics of valve if you have any

white855T said:
Vacuum actuator for vent has a torn diaphragm. Common problem. Only source is the junkyard. Sometimes new/nos one pop up on ebay.
Click to expand...

pics of diaphragm?

XxJenoxX said:
I've got a spare or two, if that's your problem.
Click to expand...

hell yea bro. pm me
 
jvluntzel said:
Pics of valve if you have any
Click to expand...


34331151532_1.jpg
 
Kjets On a Plane said:
Not uncommon for all the air to be on the floor on a 7/9 climbing a hill with a torn vac servo I?d the check valve and all else works.

In that case,
Add a vacuum pump or crush the car, it?s not worth fixing :lol:
Click to expand...

Now now then...that's not the TB mentality! There's gotta be a ghetto hack workaround :rofl:
 
I had this same issue. I installed a vacuum pump with a vacuum switch. No cutting, no cursing. Works well.

Once vac is 2<. it turns on, Once <4 it turns off. It's connected only to the vac source for the HVAC controls.
 
Ursan said:
I had this same issue. I installed a vacuum pump with a vacuum switch. No cutting, no cursing. Works well.

Once vac is 2<. it turns on, Once <4 it turns off. It's connected only to the vac source for the HVAC controls.
Click to expand...



Could you post more pictures and information?
 
Here are pictures of a vacuum actuator that is torn and one that is good.

41120888125_5c2c309acd_z.jpg
41301160234_1f06f174f4_z.jpg


Its easier to just replace part in my opinion.
 
jvluntzel said:
Now now then...that's not the TB mentality! There's gotta be a ghetto hack workaround :rofl:
Click to expand...

Ursan and I posted the work-around/hack.

Though a world where all 7/9 owners/losers would hurry up and crush those things drove kias/corollas with 100k waranties and wasted the dealer’s time would be wonderful...

Replaced them the “right” way with another near new pnw weather actuator that will just split and go bad in a few short years. Time consuming, more bother than those worthless cars are worth.

Hack in a vac pump and switch! 760s with the early auto climate control came with an aux vac can and loud vac pump anyway :e-shrug:
 
Last edited:
Kjets On a Plane said:
Ursan and I posted the work-around/hack.

Though a world where all 7/9 owners/losers would hurry up and crush those things drove kias/corollas with 100k waranties and wasted the dealer?s time would be wonderful...

Replaced them the ?right? way with another near new pnw weather actuator that will just split and go bad in a few short years. Time consuming, more bother than those worthless cars are worth.

Hack in a vac pump and switch! 760s with the early auto climate control came with an aux vac can and loud vac pump anyway :e-shrug:
Click to expand...

You have a link to your thread?

Thanks! I am so glad to hear about this workaround :D
 
You must log in or register to reply here.
Back
Top