This is basically Part 4 in a quest to solve P2646 for my brother's Honda Accord. P2646, which is an OBD-II generic code for the engine control module (ECM) detecting the 'A' rocker arm actuator control circuit for bank 1 has a performance problem or is stuck in the off position.
My brother's Honda developed acceleration problem (choppy, shuddering, stumbling & loss of power) while driving and the engine light on the dash board came on. When checking the error code using OBD-2 diagnostic tool, it displayed P2646.
Parts you might need & links to buy:
1. 15815-RAA-A01 - Solenoid Gasket Spool Valve Filter Screen | amzn.to/2RsLWjW
2. 15845-RAA-A01 - VTC Filter / Gasket Assembly | amzn.to/2GRU1fJ
3. 15810-RAA-A03 VTEC Solenoid Spool Valve w/Timing Oil Pressure Switch & Gasket (Replace # 15810-PNE-G01 15810-PPA-A01 15810-RAA-A01) | amzn.to/2Fm9HI0
In this video, we will show you how to re-install the VTC Strainer Gasket Filter Screen Assembly located in the front of the engine right behind the pulley tensioner. We have also remove and replaced the VTEC Solenoid Spool Assembly (with Oil Pressure Switch) and the valve strainer gasket behind the engine as well. Please watch other parts below:
Part 1: • I Got Code P2646: What... (What Does It Mean? Symptoms, Causes, How To Solve)
Part 2: • Solving Honda P2646 Pa... (How To Replace The VTEC Solenoid Spool Valve Assembly, Oil Pressure Switch, Gasket)
Part 3: • Solving Honda P2646 Pa... (How To Remove The VTC Gasket / Strainer)
Part 4: • Solving Honda P2646 Pa... (How To Re-Install The VTC Screen)
Part 5: • SOLVED! P2646 CODE: Ho... (Full-Length Video How To Remove & Install VTC Filter)
Part 6: How to fix common Oil Leaks for Honda
What causes the P2646 code or what triggers it?
The ECM detects a problem in the rocker arm system for bank 1.
The oil passages are clogged or the oil pressure is not up to specifications.
The rocker arm actuator is clogged with sludge or is sticking intermittently.
The engine may have excessive sludge binding the rockers from moving or the oil is too thick.
The incorrect oil viscosity is being used.
Engine oil level is too low, PCM failure, sensor failure & wiring issue
What are other symptoms of the P2646 code?
The engine valve train will not move as designed causing a low power condition.
The Check Engine Light will be illuminated.
The valve train may be excessively noisy if one or more rockers are stuck in the incorrect position.
Based on our research and inspecting my brother's Honda Accord, we concluded that there must have been an oil leak and/or sludge blocking the flow of oil inside the engine. We didn't want to think that we should remove and replace the rocker arm, or even the oil pressure switch and the solenoid. There must be something simpler and easier to fix.
The first thing we wanted to do was to clean the engine using SeaFoam. Sea Foam is specially formulated to safely and slowly re-liquify gum, sludge, varnish and carbon deposits from the hard parts in your engine so they can be flushed out of the system.
Afterwards, we planned to drain and change the oil and the filter, followed by replacing the gasket / strainer for the VTEC Spool Valve in the back of the engine. We would also replaced the front VTC strainer. Many people recommended replacing the entire Spool Valve Assembly which consists of the Timing Oil Pressure Switch, Gasket with strainer and the heat shield, but genuine OEM too expensive, so we'll keep the old one.
Apparently Code P2646 is fairly common for Honda sedan cars and SUVs such as Accord, Civic, CRV, CRZ, Element, Fit and Acura RSX, especially 7th and 8th generations model years such as model years 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 & 2012.
What does a rocker arm actuator do?
The rocker arm actuator is an oil pressure switch which controls the flow of oil to critical upper engine cylinder head components. The Rocker Arm Control Solenoid supplies hydraulic pressure to the Variable Timing mechanism. This allows the VTC System to adjust valve timing as needed. The engine's control module (PCM) uses the Rocker Arm Oil Pressure Switch to verify correct oil pressure for proper activation of the Variable Timing mechanism. If the PCM does not see the correct voltage signal back from the Rocker Arm Oil Pressure switch, the PCM will set code P2646.
Be sure to watch our other DIY auto repair videos, diagnostic ideas, and how-to fix them on EyeOnAiman's youtube channel and facebook page.
You can watch all of Aiman's auto repair videos in the following playlist: • How To Remove Alternat...
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Recording Date: January 18, 2020
Video URL: • Solving Honda P2646 Pa...