The 5 Most Common 3rd Gen Dodge Ram Problems

The 2002-2008 Dodge Ram 1500, 2500, and 3500 is a great line of trucks, but like most vehicles, it has common issues owners typically experience. In this post, we cover the top problems of the 3rd gen Dodge Ram, ranging from an engine that keeps misfiring to transmission problems. Learn what their symptoms are, why they happen, and how to fix them with these expert tips.

Top 5 Issues on the 3rd Gen Dodge Ram (2002-2008)

1. Engine Misfires

Symptoms of Engine Misfires

• Check engine light for misfire codes P0300-P0308

Causes of Engine Misfires

• Bad spark plugs, bad ignition coils, worn spark plug wires, bad fuel injectors, and carbon build-up in the engine can all cause misfires.
• On the 3rd gen dodge ram, carbon build-up in the engine is a common problem that causes frequent misfires.

How to Fix Engine Misfires

• If the ignition coil, spark plugs, or spark plug wires are worn, replace them. We recommend replacing the spark plugs and ignition coils together

• To remove carbon build-up inside the engine, there is a de-carbon procedure where you can add specialized cleaner into the intake while the engine is running to improve performance and reduce misfires
• To the clean the fuel injectors, a cleaner kit can add specialized cleaner into the fuel lines or the intake to clean off carbon from intake parts like the throttle body
• Specialized aerosol cans can also assist with engine cleaning. The procedure usually involves inserting the can to the intake tube and having an assistant press the accelerator pedal
• Fuel cleaner made specifically for the gas tank may also help fix this problem

2. No Heat or a Bad Heater Core

Symptoms of a Bad Heater Core in the 02-08 Dodge Ram

No heat flows out of the vents when the heat is turned on

Causes of a Bad Heater Core

The heater core provides heat by sending it to the cabin after it cools down the coolant. A heater core that clogs from sediment and contaminants in the coolant affects the flow of coolant. Less coolant means there’s less opportunity for heat.

How to Fix a Bad Heater Core

• The heater core is located back against the firewall. Two coolant hoses traveling into the firewall lead to it.
• One potential fix is to remove the hoses from the water pump that lead to the heater core and flush the heater core out with a garden hose to remove the sediment. After this, replace the coolant as the heater core is part of the cooling system.
• Once completed, confirm if there is heat. This fix may work for some time until a new heater core needs to be installed.
• A long-term fix is to replace the heater core, and confirm there are other issues with the cooling system.

3. EVAP System Codes

Signs the 3rd gen Ram has an EVAP code

Check engine light is on for EVAP codes P0440 and P0441

Causes of EVAP System Codes

• Loose or broken gas cap
• Stuck open or leaking EVAP purge valve

How to Fix EVAP System Problems

Fixing the Gas Cap

• Confirm the gas cap is tightly secured and not loose
• Inspect the gas cap seal for breaking, cracking, or tearing
• If the gas cap isn’t tightening or has a broken seal, replace it

Fixing the EVAP Purge Valve

The EVAP purge valve is usually located in the engine bay underneath the fuse box, but if not it’s usually attached to the engine. To find it, follow the vacuum lines and the lines that go to the back of the vehicle. It is easy to replace and usually just requires disconnecting the electrical connector and the hoses attached to it.

4. Engine Stalling

Signs the 02-08 Dodge Ram Has a Stalling Problem

Vehicle stalls when driving

Causes of Engine Stalling

Carbon build-up on the throttle body

How to Fix Engine Stalling

1. Remove the throttle body
2. Clean the throttle body of any carbon deposits
3. Clean the throttle body blade of any carbon deposits without removing the blade
4. To reinstall the throttle body—you will need to complete an “idle relearn procedure”

How to Complete an Idle Return Procedure

1. Disconnect the negative battery terminal for at least 90 seconds
2. Let the vehicle power down
3. Reconnect the negative battery terminal
4. Turn the key to the ON position without starting the truck, and wait for some time—at least 10 seconds
5. Turn the vehicle off and the procedure should be complete

5. Transmission Problems—Transmission Failure and Bad Transmission Solenoid Packs

Symptoms of Transmission Problems on the 3rd gen Ram

• The transmission shifts differently or feels like it’s slipping
• Check engine light is on with transmission code P0150

Causes of Transmission Problems

Transmission problems on the 02-08 Dodge Ram don’t always mean the truck needs a new transmission. Sometimes the transmission solenoid fails and causes similar symptoms to a failed transmission

How to Fix Transmission Problems

• Keep up with transmission service intervals and check the transmission fluid regularly for the right level and color, which should be red. Double check the owner’s manual for instructions on how to properly change the fluid.
• The solenoid packs are located underneath the transmission pan. You will need to remove the transmission pan to access the solenoids

Fix Your 3rd Gen Dodge Ram Yourself with 1A Auto’s How-to Videos

Find how-to videos related to these repairs and more for the 02-08 Dodge Ram and many other years, makes, and models with 1A Auto’s how-to video library.

Shop 3rd Gen 2002-2008 Dodge Ram Parts Featured in This Article

• Ignition Coils
• Spark Plug Wires
• Heater Core
• Gas Cap
• EVAP Purge Valve
• Throttle Body
• Transmission Solenoid
• Transmission Pan

Related Content

• Which fault codes are ignition-related?
• Bad Fuel Injector Symptoms [Advice to Diagnose & Fix]
• P0300 code: Mechanic advice to diagnose and fix
• Signs of a Failing or Bad Ignition Coil
• How to Test If an Ignition Coil Is Bad
• Gas Cap Throwing a Check Engine Light? [Diagnose & Fix]
• My Car Won’t Start After Getting Gas & How I Fixed It
• Throttle Body Cleaning Tips [Expert Advice]
• Signs of transmission failure and ways to prevent it
• Is Your Dodge Ram Dashboard Cracking? Here’s How to Fix It
• The 5 Most Common 2nd Gen Ram Problems

3rd Generation Dodge Ram Model Years

• 2002 Dodge Ram 1500, 2500, 3500
• 2003 Dodge Ram 1500, 2500, 3500
• 2004 Dodge Ram 1500, 2500, 3500
• 2005 Dodge Ram 1500, 2500, 3500
• 2006 Dodge Ram 1500, 2500, 3500
• 2007 Dodge Ram 1500, 2500, 3500
• 2008 Dodge Ram 1500, 2500, 3500