A/C intermittent
Thread Starter
|
New User
Joined: Oct 2004
Posts: 18
Likes: 0
From: Atlanta, Ga.
A/C intermittent
I have 98 Nav. w/48K ,electronic temp control When I have the A/C on it works great, nice and cold but when I accelerate anything greater than a grandma I lose my cold air and hear a clunk like the blend door or another door in their just slammed shut. Talked to the dealer and they said something about a check valve not working correctly. Sounds like its vacuum related though after turning the A/C on off a few times I get the my cold air back.
Tuned
Joined: Feb 2003
Posts: 495
Likes: 0
From: Cincinnati, Ohio
I would check all of the vacuum lines to make sure you don't have a leak. Are you sure the AC quits and it isn't just blowing in the defrost mode? This would indicate the vacuum leak since defrost is the default position for the system.
John
John
Thread Starter
|
New User
Joined: Oct 2004
Posts: 18
Likes: 0
From: Atlanta, Ga.
John,
All the vacuum lines in the eng. compartment look OK, I guess I'll have to remove the dash to get a look at the vacuum lines going to the plenum. When the cold air turns to hot air you hear a thump behind the dash (radio area). The air is still blowing at the same rate out of the a/c vents. The ETAC (electronic temp. air control) bite test shows no faults. I removed the ctr. console between the front seats and removed the blend door actuator, toggled the temp. from full hot to full cold and seen the actuator operating correctly. I really don't have a lot of room to use an inspection mirror to look into the plenum from where I removed the actuator to see if anything doesn't look right. I'm sure not looking fwd to removing the dash.
All the vacuum lines in the eng. compartment look OK, I guess I'll have to remove the dash to get a look at the vacuum lines going to the plenum. When the cold air turns to hot air you hear a thump behind the dash (radio area). The air is still blowing at the same rate out of the a/c vents. The ETAC (electronic temp. air control) bite test shows no faults. I removed the ctr. console between the front seats and removed the blend door actuator, toggled the temp. from full hot to full cold and seen the actuator operating correctly. I really don't have a lot of room to use an inspection mirror to look into the plenum from where I removed the actuator to see if anything doesn't look right. I'm sure not looking fwd to removing the dash.
Post Fiend
Joined: Feb 2003
Posts: 6,940
Likes: 2
From: Eastern WA
I think your dealer gave you a good heads up on the check valve. They are sometimes located in the vacuum line; other times they are integral with the vacuum reservoir. Much easier to check that first as opposed to pulling the dash.
FTE Leadership Emeritus
Joined: Jan 2003
Posts: 161,999
Likes: 75
From: 3rd Rock
...Welcome CWWright, to Ford Truck Enthusiasts! Please read the Guidelines, it will help you to navigate through and understand this site.
Stick around someone will be by shortly to answer your question.
We are happy you have chosen the best source for Fords!
Enjoy FTE....and
JOIN CLUB FTE -SUPPORT THE FORUMS!
…..See you on the boards.
Stick around someone will be by shortly to answer your question.
We are happy you have chosen the best source for Fords!
Enjoy FTE....and
JOIN CLUB FTE -SUPPORT THE FORUMS!
…..See you on the boards.
Trending Topics
Hotshot
Joined: Jan 2004
Posts: 19,768
Likes: 1,082
From: St Louis
I'd say you have a broken blend door. The dealer person was unfamiliar with how the temperature control works in the truck as it is not vacuum operated or he/she misunderstood your description of the symptoms.
There is an arm that connects to the BDA to the door. When it breaks, you loose control of the temperature and the door will flop open or closed depending on what the truck is doing. Blend door repair requires removal of the dash.
Vacuum leaks will cause the system to default airflow to the defrost vents so that can be eliminated as a likely reason for your symptom.
Steve
There is an arm that connects to the BDA to the door. When it breaks, you loose control of the temperature and the door will flop open or closed depending on what the truck is doing. Blend door repair requires removal of the dash.
Vacuum leaks will cause the system to default airflow to the defrost vents so that can be eliminated as a likely reason for your symptom.
Steve
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
New User
Joined: May 2005
Posts: 1
Likes: 0
First I want to say hello since I have been reading several threads but this will be my first posting. I have a 2000 Ranger and have the same problem with the A/C. I had it recharged and according to the technician, there was no leak. It will work well for a while and then the cool air will stop. Sometimes the compressor's clutch will not engage and sometimes it will. I have changed the relay which is always hotter than the other ones. Thanks.
