Truck Trend Garage: 2005 Ford Escape Air-Conditioning Noise

The Belt Way

Alex Steele
Dec 7, 2012
Q: I have a 2005 Ford Escape with 85,000 miles. When idling with the air-conditioning on, I hear a clicking noise from the engine. I noticed that the belt tensioner seems to move back and forth along with the noise. So I changed the serpentine belt, but it didn't make any difference.
A: There are a couple of steps in performing an accurate diagnosis for this type of noise. A required tool is a mechanic's stethoscope, but in a pinch, a long screwdriver held to your ear can accomplish the same thing. While the engine is running and the noise is pronounced, touch the end of the stethoscope to each and every component driven by the serpentine (drive) belt. I probably shouldn't have to mention this, but I will: Do not touch any moving parts. If you're listening to the A/C compressor, listen at the stationary housing, not the pulley spinning at 1000 rpm. Listen carefully. Of course, you're going to hear noise everywhere you go, but you're looking for an exceptionally loud noise that mimics what you're hearing with only your ears. This can be deceiving, and there's no replacement for experience. Noise from one component may transmit through the drive belt (or engine block), and sound like it's coming from somewhere else. Once you narrow the source down to one or even two components, here's the trick: Shut down the engine, remove the drive belt, and listen to each component again, only this time while spinning each component's pulley by hand. Often a worn bearing will be night-and-day louder than the rest.
Photo 2/2   |   2005 Ford Escape Air Conditioning
The noise taking place only with the A/C on was a clue. It's possible the A/C compressor itself is causing the problem, but that's not always the case. When the compressor is engaged, it applies a much heavier load on the drive belt, and oftentimes this load will produce noise from another component. Clue two was the tensioner moving in rhythm to the noise. Drive belt tensioner failure is common, and the belt is very susceptible to producing noise when extra load from the A/C compressor or power steering pump is applied. If the tensioner is the root cause of the problem, you should hear an unmistakable bearing noise while spinning the pulley by hand.

How To Reach Alex
If you have a technical question regarding your pickup, SUV, or van, feel free to contact Alex, a master technician with the National Institute for Automotive Service Excellence. Send a letter to him in care of Truck Trend Garage, 831 S. Douglas Street, El Segundo, CA 90245, or e-mail us at trucktrend@sourceinterlink.com. Please include the VIN with your question. Due to the volume of questions received every month, we cannot guarantee that everyone's question will be personally answered or will appear in the magazine.

Can't wait for help with a problem you're having with your Truck or SUV? Ask the expert we trust here at Truck Trend Garage -- visit Alex Steele at www.RealWorldAutomotive.com.

2015 Ford Escape Specifications

VIEW ALL
Fair Market Price $22,334
MSRP $23,450
Editors' Overall Rating
Mileage 22 City / 31 Highway
Engine 2.5L I4
Horse Power 168 hp @ 6,000 rpm
Torque 170 ft lb of torque @ 4,500 rpm
See all Specifications
- OF

MOST POPULAR

Truck Trend Network

TRUCK RESEARCH SNAPSHOT

Ford Escape

Fair Market Price
$22,334
Editors' Overall Rating
Basic Specifications
MSRP: $23,450
Mileage: 22 / 31
Engine: 2.5L I4
get a free quote

Subscribe Today and Save up to 83%!

Subscribe Truck Trend Magazine

Subscribe to:

Truck Trend
Magazine

PRINT DIGITAL
Subscribe Diesel Power Magazine

Subscribe to:

Diesel Power
Magazine

PRINT DIGITAL
Subscribe Truckin Magazine

Subscribe to:

Truckin
Magazine

PRINT DIGITAL
SUBSCRIBE TO A MAGAZINE
TO TOP