Help!AC wont blow at acceleration....
#1
Member
Thread Starter
Join Date: Feb 2009
Location: Miami, Fl
Posts: 194
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Cherokee
Engine: Straight Six
Help!AC wont blow at acceleration....
Hey guys yesterday driving the jeep I noticed that my A/C stops blowing when I accelerate..As soon as I let of the gas a bit the A/C starts again, Its cold and everything but if im increasing in speed nothing comes out...Anyone know what this could be??? BTW its a 93..
Thanks in advance..
Thanks in advance..
#2
Newbie
Join Date: Jun 2010
Location: Lenoir, NC
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1998
Model: Cherokee
Engine: 4.0
I had the same problem with my '98 Cherokee, and now it will only blow through the defrost vents. If you get an answer please let me know
#3
CF Veteran
Join Date: Mar 2009
Location: Tenn. and Mich.
Posts: 28,068
Likes: 0
Received 6 Likes
on
6 Posts
Year: 2004
Model: Grand Cherokee
Engine: 4.7L V8
When this happens sometimes it's a problem with the vacuum line that comes out of the firewall near the master cylinder.
Edit: Read this thread. It may help. https://www.cherokeeforum.com/f5/hva...ncluded-49071/
Edit: Read this thread. It may help. https://www.cherokeeforum.com/f5/hva...ncluded-49071/
Last edited by ol"blue; 06-16-2010 at 05:41 PM. Reason: Added info.
#4
Member
Thread Starter
Join Date: Feb 2009
Location: Miami, Fl
Posts: 194
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Cherokee
Engine: Straight Six
When this happens sometimes it's a problem with the vacuum line that comes out of the firewall near the master cylinder.
Edit: Read this thread. It may help. https://www.cherokeeforum.com/f5/hva...ncluded-49071/
Edit: Read this thread. It may help. https://www.cherokeeforum.com/f5/hva...ncluded-49071/
#6
CF Veteran
Seems like the Vacuum tank is under the right fender behind the bumper.
If its not hooked up you don't have consistent vacuum to operate the vent switches.
If its MIA get a new one and hook it up.
If its not hooked up you don't have consistent vacuum to operate the vent switches.
If its MIA get a new one and hook it up.
#7
Senior Member
Join Date: May 2010
Location: Detroit, MI
Posts: 889
Likes: 0
Received 2 Likes
on
2 Posts
Year: 1994
Model: Cherokee
Engine: 4.0
On all modern cars, when the vacuum system leaks the HVAC system defaults to defrost only. It is intentionally engineered into the system for safety reasons. It is also how you know you have a vacuum leak.
Trending Topics
#8
Junior Member
Join Date: Jun 2010
Location: Central PA
Posts: 55
Likes: 0
Received 1 Like
on
1 Post
Year: 1999
Model: Cherokee
Engine: 4.0 L
If the dash vents switch to the defrost only when giving it a lot of gas, then the one-way check valve for the vacuum line going to the tank in the front bumper may be toast. That was my problem. The vacuum escapes back into the intake manifold when the engine vacuum drops. Its a little round plastic valve in the tube going from the intake manifold to the firewall. Pull it out and blow through it. If there is no resistance in one direction, thats the problem. I bought a new one from Autozone for $4. I have a 1999 so hopefully its the same setup.
The following users liked this post:
jesjess (07-13-2019)
#9
If the dash vents switch to the defrost only when giving it a lot of gas, then the one-way check valve for the vacuum line going to the tank in the front bumper may be toast. That was my problem. The vacuum escapes back into the intake manifold when the engine vacuum drops. Its a little round plastic valve in the tube going from the intake manifold to the firewall. Pull it out and blow through it. If there is no resistance in one direction, thats the problem. I bought a new one from Autozone for $4. I have a 1999 so hopefully its the same setup.
I’m guessing this is the price you’re talking about
#10
Could that check valve being out on the vacuum line cause this line to blow off this
My vacuum line on this piece keeps blowing off the nipple can that be caused by the check valve on the intake manifold being out?
#11
#12
CF Veteran
Join Date: Aug 2020
Location: SoCal
Posts: 1,475
Received 405 Likes
on
330 Posts
Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
Here's my suggestion. Rather than continue to bump 10 year old threads asking for a PN, start your own thread. Include symptoms and how you determined the check valve is bad and why the one you bought doesn't fix it. Perhaps you overlooked something.
#13
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,876
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Inspect all this.
Thread
Thread Starter
Forum
Replies
Last Post
jmsummers2012
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
53
04-30-2021 02:35 PM
LittleRed94
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
5
10-06-2015 08:09 PM
investinwaffles
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
1
09-24-2015 10:05 AM
Snoflwr
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
3
09-09-2015 11:43 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)