Check Engine Mercedes P2004 Code
The intake manifold air flap lever is a common failure point for Mercedes-Benz cars equipped with the M272 (350) and M273 (550) engines. When this component fails, your Mercedes-Benz will turn on the check engine light triggering any of the following codes:
- P2004 – Intake Manifold Runner Control Stuck Open Bank 1
- P2005 – Intake Manifold Runner Control Stuck Open Bank 2
- P2006 – Intake Manifold Runner Control Stuck Closed
To fix this problem, you will need to replace the intake manifold air flap lever using Repair Kit 2721402401. This part is located by the intake manifold. When the lever breaks, the intake air flaps can no longer be controlled by the vacuum actuator. The flap may break due to wear or excessive carbon built up near the intake valves. Over time the plastic becomes brittle and eventually fails. Once the lever breaks, the pull rod disconnects from the manifold air flap lever. The part is the same design for the M272 V6 and M273 V8 engines.
Symptoms of a broken manifold air lever
- Check engine light ON
- Poor Idle
- Loos of Power
Mercedes P2004 Cause
Weak material used in constructing the intake manifold air lever is the main common cause of Mercedes P2004 codes. If you have a broken manifold air lever, you may want to consider replacing your old lever with a high-strength aluminum design. Go to Amazon to check the price on Aluminum Mercedes Intake Manifold Air Flap Kit. An aluminum part is less likely to fail again and is a much better solution than the plastic OEM lever.
Solution: Replace the broken manifold lever
The least expensive solution is to replace the broken Mercedes Benz M272/M273 Intake Manifold Air Flap Runner using a repair kit. Note that in the past, dealers did not sell the lever only but sold a complete intake manifold. Buying a new intake manifold is too expensive and NOT necessary. This problem can be fixed by replacing the manifold air flap lever only.
To complete this repair at a minimum, you will need the following:
- Mercedes Benz M272/M273 Intake Manifold Air Flap Runner Repair Kit
- Intake Manifold Air Flap Runner Repair Kit 2721402401 for Mercedes-Benz C230 C280 2006-2007 CLK350 E350 2006-2011 C300 C350 GL450 ML350 BASE R350 4MATIC SLK280/350
- Aluminum M272 M273 Intake Manifold Air Flap Runner Repair Kit
- 07-11 Mercedes-Benz GL450 Intake Manifold Air Flap Runner Repair Kit 07 08 09 10 11
- Silicone Grease
- Thread locker
Consider replacing the intake manifold gasket as well.
- Remove the intake manifold from the engine. Label all the cables and hoses that you disconnect. Take several pictures before you start disconnecting wires. This is the most time-consuming process and will take one to two hours.
Once the intake manifold is removed from the engine, cover the intakes with tape to avoid debris, dirt, and tools falling into the cylinders.
- Remove the vacuum actuator rod by pushing it out of the lever using a flat screwdriver.
- Next use a T30 Torx bit to remove the bolt that holds the lever. Be careful when removing this bolt, as it easily strips.
- Install the central bolt. Use a thread locker and tighten the bolt to 8 ft-lb.
- Place some grease on the ball studs and then press the connecting rod until it locks in the ball studs.
- Once the vacuum actuator, connecting rod, and manifold lever are connected, test them by moving the manifold flaps. Ensure that no restriction can cause the manifold flaps to get stuck.
- Install the intake manifold in reverse order. Make sure to reconnect any vacuum lines that you disconnected.
- The check engine light should turn off on its own after driving the car for several days. Assuming you fix the problem correctly and no other codes are pending. If you would rather clear the codes, then use an OBD II code reader to clear the check engine light by following these steps.
- Plug the code reader in the OBD II port under the dash.
- Turn the key to position II, do not start the engine.
- Press the read codes button.
- After displaying the codes, you can erase them by pressing the erase button on your scanner.
What Scanner to Use for Troubleshooting/Diagnosing Mercedes-Benz Problems?
If you’re experiencing problems with your Mercedes-Benz, a YOUCANIC full system diagnostic scanner can help you troubleshoot the issues. This advanced diagnostic tool can read and interpret the fault codes stored in your car’s computer system, providing detailed information about any problems with the engine, transmission, brakes, or other critical systems.
The YOUCANIC scanner can also perform diagnostic tests on various systems, including the ABS, airbag, and steering systems, to help pinpoint the root cause of any issues. With this information, you can make more informed decisions about repairs and maintenance, saving time and money on costly repairs.
Video Mercedes P2004- Throttle Lever Repacement
- Affected Models: C230 2006-2007 C280 2006-2012 C350 CLK350 E350 ML350/450 R350,SLK280/300/350,Engine M272 M273
- Part Number: 2721402401 2721402101 2721402201
Hi Mercedes Medic,
I notice there are 2 different types of repair kits available for the Intake Manifold. I have the P2006 code (stuck closed intake runner flap for bank 1). Which repair kit should I purchase? These are the 2 options.
The difference between these two options being that #1 simply comes with the lever and connecting rods, and #2 comes with the lever and actuator (no rods). If #2 is the correct repair kit, I will also be purchasing a set of gaskets to go with it. Thank you for your help!
Could the sensor that monitors the flaps be bad and trips a p2004 code. I have the same problem all of the machanical parts are not broken. gonna runs a separate valcuum line to the actuator to see if it’s working.
Yes, it very well can. Let us know what you find out.
What if you have a code P2004, no broken lever and internal flaps are intact and move freely. Seems like the actuators are not getting triggered, could it be a vacuum leak? A solenoid? A change over valve? I’m stuck here and can’t figure out what it is. When the car is at 4000 RPMs I look in the front of the manifold and the actuators dont move. Please help.
I would check the solenoids if that’s the case.
Had the P2006 code on my 2007 C230, butterfly flap was broken, replaced it. Everything was fine and the code disappeared. Later that day I got a P2004 code, I removed the manifold and inspected, everything was fine and working, no broken parts and the inside flaps moved freely without resistance. This code P2004 persists. Could it be the Solenoid? And how can that be diagnosed? When I have have someone in the car revving it at different Rpms I don’t see any movement on the intake actuators. Could it be a vacuum issue? I’m scratching my head on this one.
Did the same as Kevin 👆 I have a 08 C350 and I replaced the broken part, couple months passed and now I’m getting a P2004 error code!!??