
The Mustang is a classic car but each generation also has its classic problems. Some common 5th gen Ford Mustang problems include a clogged catalytic convertor, and problems with the transmission and throttle body. Find out the top issues and how to fix them as we cover the five most common problems with the 5th generation of Ford Mustangs, years 2005 to 2014.
Top Issues on the 5th Gen Ford Mustang (2005-2014)
1. Clogged Catalytic Convertor
Symptoms of a Clogged Catalytic Convertor
- Difficulty starting the engine
- Intermittent engine power
- Intermittent rattling underneath the vehicle
Causes of a Clogged Catalytic Convertor
- The honeycomb filter can fall off kilter and affect the flow of exhaust gases, causing a lack of power or rumble
- On the 05-14 Ford Mustang, the number one cause for no start problems is a clogged catalytic convertor
How to Fix a Clogged Catalytic Convertor
Remove the driver and passenger side upstream oxygen (O2) sensors and try to start the car. If it starts, it’s start up problems were caused by a clogged exhaust.
2. Transmission Problems
Symptoms of Transmission Problems on the 5th Gen Mustang
- Flashing overdrive light
- Hard shift when accelerating or braking
- Leaking transmission
Causes of Transmission Problems
The 5th gen Ford Mustang has a sealed transmission and does not have a transmission dipstick. It is not meant to be serviced unless it has problems.
How to Fix Transmission Problems
The transmission is not meant to be serviced, flushed, etc. If there is a problem with the transmission, see a professional or the dealership.

3. Timing Chain Issues
Symptoms of Timing Chain Issues
- The timing chain jumps sequence
How to Test for a Bad Timing Chain
Test the timing chain by connecting a timing light to the battery and marking the harmonic balancer. If the mark holds steady with the light, the timing chain is functioning. If the mark bounces with 1-2 inches of the light, the timing is off.
4. EVAP Problems
Symptoms of EVAP Problems
- Check engine light for code P0456
Causes of EVAP Problems
The most common replacement for this trouble code is the gas cap
How to Inspect the Gas Cap
Check the gas cap for looseness, cracking, or a broken gasket
5. Rough Running Engine Problems
Symptoms of a Rough Running Engine Problems
- Check engine light for code P061B and code P2103
Causes of Rough Running Engine Problems
- The mass air flow (MAF) sensor usually triggers code P061B
- The throttle body usually triggers code P2103
How to Fix Rough Running Engine Problems
Confirm the hose clamps on the intake tube are tight and there are no tears on the tube. Confirm there are no other ways air can get in the system. If this is the case, replace the MAF sensor
You can attempt to clean the throttle body but because it is cable-free, it usually needs to be replaced
Fix Your Own Ford Mustang
Fix these and other parts on your own Ford Mustang with expert instructions in 1A Auto’s how-to videos
Shop 5th Gen Ford Mustang Parts Featured in This Article
Related Content
- Exhaust Leak? Expert Advice to Diagnose & Fix
- Is your Transmission Slipping, Jerking, or Low on Fluid?
- Signs of transmission failure and ways to prevent it
- Timing Belts Vs. Timing Chains
- Gas Cap Throwing a Check Engine Light? [Diagnose & Fix]
- MAP vs. MAF vs. IAT Sensors
- How to Test a MAF Sensor
- Throttle Body Cleaning Tips [Expert Advice]
Model Years of the 5th Generation Ford Mustang
- 2005 Ford Mustang
- 2006 Ford Mustang
- 2007 Ford Mustang
- 2008 Ford Mustang
- 2009 Ford Mustang
- 2010 Ford Mustang
- 2011 Ford Mustang
- 2012 Ford Mustang
- 2013 Ford Mustang
- 2014 Ford Mustang

