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Dodge Ram 2002-2008: How to Clean Throttle Body

The throttle body is connected to a cable attached to your gas pedal on the 4.7 and 3.7 engines (minus some 2008 year models). The 5.7 Hemi engine uses a drive by wire system (electronic) to control the throttle body's movement. When carbon becomes lodged between the throttle plate and the throttle body, the engine is not able to receive enough air at idle.

By Weston Chadwick - July 20, 2015
Contributors: CarGuyOhio

This article applies to the Dodge Ram 3rd Generation (2002-2008).

A cable-driven throttle body works by using a mechanical linkage to respond in exactly the same way as your gas pedal. An electronic throttle body, on the other hand, is different. As the computer monitors the engine's operation, it can detect instances where more or less air flow would improve performance and emissions. The stepper motor controlling the throttle plate can be adjusted within the computer's programmable limits to gain these advantages.

As the miles pass, carbon begins to buildup between the throttle plate and throttle body. Depending on how much carbon buildup there is, your engine may not have the needed air flow to start the engine. Idle and low rpm cruising will also be affected. On the Hemi 5.7 engine, your idle may be noticeably higher to make up for the loss of air due to the carbon buildup.

Materials Needed

  • Throttle body gasket (5.7 engine owners)
  • Rubber gloves
  • Safety glasses
  • Flat head screwdriver
  • 10mm wrench
  • 3/8" or 1/4" ratchet
  • 10mm socket
  • 8mm socket
  • Non-chlorinated brake cleaner
  • Electrical tape
  • Q-tips

Step 1 – Disconnect the battery

Remove the negative (black) battery cable with a 10mm wrench. Make sure the cable is far enough from the battery terminal to avoid accidental contact.

Pro Tip

You can also wrap the cable with electrical tape to help it avoid contacting the battery and sparking.

Step 2 – Remove the resonator box

Refer to Step 1 of the Related Article: How to Replace Ignition Coils and Spark Plugs for this procedure.

Step 3 – Remove the throttle body (5.7 owners only)

For the 5.7 engine owners, begin by removing the connector at the top of the throttle body. On the side of the connector plug, you will see a flexible tab. Squeeze this tab while pulling the connector plug away from the sensor. Four bolts with 8mm heads hold the throttle body in place. Remove them and carefully pull the throttle body away from the intake manifold. If it's stuck in place, use a flat head screwdriver or small pry bar to separate them.

The 4.7 and 3.7 engines use a cable-driven throttle body. Unlike the Hemi's throttle body with an electric motor, moving your throttle plate manually will not affect the engine's running characteristics.

Note

Some 2008 4.7 and 3.7 engines use an electronic throttle body as well. Fro these engines, follow the same procedure as the 5.7 engine.

  • Figure 1. Dodge Ram 5.7 throttle body diagram.
  • Figure 2. V6 engine pictured; the throttle body cable lever is on the right side.

Step 4 – Clean the throttle body

Use non-chlorinated brake cleaner to remove the carbon buildup on the 5.7 engine's throttle body. Spray the cleaner onto a rag and wipe away the black carbon. Be careful not to get any on the electronic components. You can use a Q-tip or similar item to remove as much carbon around the crevices of the throttle plate as possible.

Non-chlorinated brake cleaner or throttle body cleaner can be used to remove the carbon on the 4.7 and 3.7 cable-driven throttle bodies. You can use a rag or spray the cleaner directly into it. Do your best to wipe away the carbon between the throttle plate and housing.

Dry your throttle body off with light amounts of compressed air or let it air dry. Lint-free rags are your friends here.

Step 5 – Re-install the throttle body and resonator box

3.7 and 4.7 owners only need to re-install the resonator cover, then re-connect the negative battery cable to finish the installation.

5.7 engine owners are suggested to replace their throttle body gasket at this time. Start the four 8mm throttle body bolts with your fingers. Snug them up with your ratchet (about 5 ft. lbs.) in a criss-cross pattern. Plug the electrical connector back in. Now re-install the resonator cover and attach the negative battery cable.

Step 6 – Calibrate the electronic throttle body

The drive by wire system needs to be calibrated with a specific procedure.

  1. Turn the ignition to the "on" position.
  2. Leave the ignition switch in the "on" position for a minimum of 10 seconds. This will allow the PCM to re-learn electrical parameters.

Featured Video: How to Clean Throttle Body

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