A/C thunk and i mean thunk
Thread Starter
|
Elder User
Joined: Mar 2005
Posts: 644
Likes: 0
A/C thunk and i mean thunk
Aright everytime i turn my AC on when startin the truck i hear this clunk and its loud. Anyone else have this or know what it is...When i first got my truck the ac came out the defrost vents they fixed that but now im gettin this clunk noise....should i take this in or do yall know what it is..
Senior User
Joined: Jul 2004
Posts: 285
Likes: 0
From: north louisiana
Mine does it. sounds like a loud WHUMP!!!!! when the doors down low under the dash somewhere slam shut. I actually thought I hit something in a parking lot once, got out to look around. Finally got used to it, but it still startles me once in a while, especially when I just went into gear and started moving.
Senior User
Joined: Oct 2004
Posts: 157
Likes: 0
From: Orange County, California
Lately, my AC makes a fluttering noise in the dash board diverter valve that sends the flow to the defrost or normal dash vents. After a bout of the diverter fluttering, the air flow, (ac or normal vent) will only come out the defrost holes, no matter where I set the controls. It has happened 3 times and usually flops back to normal after about 30 minutes or another re-start. It it keeps doing it, might need a trip to the shop. Besides that, engine is running strong. Last tank of fuel got a calculated 16.7 mpg, on a trip to Mexico with a fair load inside that huge Leer 122 camper shell. (picks in my gallery. Even a Kawasaki KLX 300 motorcycle or Suzuki King Quad can fit inside that camper shell).
Last edited by Dieselhound; Jul 30, 2005 at 11:27 PM.
Posting Guru
Joined: Oct 2003
Posts: 1,332
Likes: 4
From: Baltimore
[QUOTE=Dieselhound]Lately, my AC makes a fluttering noise in the dash board diverter valve that sends the flow to the defrost or normal dash vents. After a bout of the diverter fluttering, the air flow, (ac or normal vent) will only come out the defrost holes, no matter where I set the controls. /QUOTE]
Sounds like a vacuum problem. Check inside for a hissing noise around the dash, which would indicate a bad valve or loose hose. Also check the vacuum lines under the hood for splits and being loose.
Sounds like a vacuum problem. Check inside for a hissing noise around the dash, which would indicate a bad valve or loose hose. Also check the vacuum lines under the hood for splits and being loose.
Trending Topics
Elder User
Joined: Mar 2005
Posts: 526
Likes: 4
From: New Jersey
Another common thing that causes that is the vacuum pump. The diesel trucks have an electric vacuum pump located on the right fender well next to the starter relay and vacuum reservoir. This pump is always powered up with the key in any position and it is controlled by way of a built in vacuum sensor. It is not uncommon for them to just quit working. You can try smacking it with a screwdriver handle, check for voltage and ground at the connector or inspect the vacuum lines for breaks and disconnected lines. When the system loses vacuum, it defaults to the defrost position - the tell-tale sign of a complete loss of vacuum!
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
Senior User
Joined: Oct 2004
Posts: 157
Likes: 0
From: Orange County, California
Thanks for the excellent tech info. If the fix involves whacking the part, spraying it with WD-40, volt checking it, replacing a hose or component, I can tackle it. One of my friends at work always says: If it isn't moving and should, spray Wd-40 on it. If it is moving and shouldn't, put duct tape on it;-). Nasa needs to use more duct tape on their shuttle.
Mountain Pass
Joined: May 2004
Posts: 226
Likes: 6
I noticed the AC THUMP right away on my 05. It drove me nuts for a while but I've gotten used to it. Just turn the radio up loud and you can hardly hear it.
Also my wifes Navigator just started the AC out the defrost vent trick. It switches to the defrost vents for a few seconds and then back. I think it must have a vacuum leak or something.
Also my wifes Navigator just started the AC out the defrost vent trick. It switches to the defrost vents for a few seconds and then back. I think it must have a vacuum leak or something.
Thread
Thread Starter
Forum
Replies
Last Post