Fan blower fades away on acceleration? Back on idle

H

hillcameron415

NAXJA Forum User

Location

So Cal

• Apr 26, 2016

• #1

1990 xj 4.0 ax15

Not sure what would cause this. I just recharged my a/c and got her blowing cold. But just to learn she doesn't like to blow :yelclap:
I played with vacuum lines when doing the intake/exhaust gasket a while back. Maybe I messed some up. Any ideas?
Thanks in advanced

 

four_shot

NAXJA Member

NAXJA Member

Location

Waukegan, IL

• Apr 26, 2016

• #2

That's where I'd start. It sounds like the vacuum reservoir is disconnected. The fan probably isn't slowing down. The mode doors are probably defaulting back to defrost when accelerating and engine vacuum is low.

 

H

hillcameron415

NAXJA Forum User

Location

So Cal

• Apr 26, 2016

• #3

four_shot said:

That's where I'd start. It sounds like the vacuum reservoir is disconnected. The fan probably isn't slowing down. The mode doors are probably defaulting back to defrost when accelerating and engine vacuum is low.

Click to expand...

Where is that? Is that on the top of the firewall, towards passenger side? And am just looking for disconnected tubes?

 

D

Dragonlich1961

NAXJA Forum User

Location

Ohio

• Apr 26, 2016

• #4

Vacumm resivor is under the passenger corner of your bumper. Small black foot ball.

 

H

hillcameron415

NAXJA Forum User

Location

So Cal

• Apr 26, 2016

• #5

When driving I just checked the defrost vents when it fades away, and that's definitely the case. Just switching vents.

So when I find my vacuum Reservoir, what should I be looking for? Which vacuum lines would cause this?

 

D

Dragonlich1961

NAXJA Forum User

Location

Ohio

• Apr 26, 2016

• #6

The resivor is under your front bumper on the right. Small black ball. There will be a line that runs up from the ball, down the length of the passenger fender ( cruise plugs into this line). Then it travels across your firewall to the intake. There will be a one way valve at the intake to seal the system when the engine is off.

Some where on this line is the out put to to the HVAC system. A break anywhere will cause the vacuum leak. Even the check valve will cause it if it's bad

 

H

hillcameron415

NAXJA Forum User

Location

So Cal

• Apr 27, 2016

• #7

I'm checking all the lines now.

Also, under my passerger side dash, there's an orange vacuum line hanging from somewhere any guesses where it
goes?

 

Ecomike

NAXJA# 2091

NAXJA Member

Location

MilkyWay Galaxy

• Apr 27, 2016

• #8

hillcameron415 said:

I'm checking all the lines now.

Also, under my passerger side dash, there's an orange vacuum line hanging from somewhere any guesses where it
goes?

Click to expand...

It goes to one of the HVAC damper door control valves or dash control.