Hi everybody!

I had a check engine light come on, could not rev above 3k RPM without serious lurching/stutter. I pulled the codes and it came back P2647 for a bad VVT switch. I took it to a mechanic who would like $700 to replace it ($375 for dealer part that I found for $125 from Honda), but it seems like I could replace it myself by buying a replacement assembly, unbolting, unplugging, and then plugging in the new one and bolting it on. I'm good at fixing things, but don't usually work on my car. (This is actually the first issue it's had in 95,000 miles.)

I have two questions:

1. Is this the correct part? VALVE ASSY, SPOOL (15810-RNA-A01)
2. Any other advice/warnings before I attempt the repair? I normally fix computers, vacuums, tools, etc., and this seems to be a relatively simple replacement. What should I be careful about, and what other steps should I take besides just removing the old and replacing the new?

I'm going to check if my Chilton manual covers this replacement once I get home.

The code doesn't automatically mean the valve is bad. There are other things that can cause the code.

First make certain it wasn't low on oil.

Second, do you have freeze frame data that goes with the code?
Post it if possible, I'd like to know what the running conditions were when it set the code.

How long had it been running when the CEL popped on? (3 seconds after a startup?)



Third......Who did the last oil change, and how long ago was it done? What oil filter is on it?

This may sound crazy.....and a whole lot cheaper....
replace the oil filter with one from Honda. (or just change the oil and use a Honda filter, or have the dealer do an oil change using a Honda filter).
Erase the codes, drive it, then see if it returns the same code later on.

Hi! Thanks for helping!

Good idea. I had heard this was a possible cause. I checked oil levels and it's not low.

No data to go with the code. I had it read at an auto parts store, then took it for diagnostics to my mechanic. I would have paid him to replace it, but he wanted $375 for what he admits is $125 online. He confirmed their tests confirmed the same.

Lamp comes on immediately and remains on until the vehicle is shut off.

NTB. (I don't know if the chain has a bad reputation here, but the mechanics at mine are knowledgeable, friendly, and go the extra mile.)

If I detach and reattach the battery, the code returns immediately. From what I read, I suspect the filter clogged with something causing the solenoid to fail.

You mean as soon as you start the engine it turns the light back on? (It takes 2.5 seconds of low oil pressure at the vtec valve sensor after startup to set this code)

Or does the CEL just never go out?
(Does the battery disconnect actually erase the code or not?)

Their discount oil filter is likely causing the oil pressure to be too low.
Get an oil change done at your Honda dealer, erase the code, and see if the code stays away.

Short of being able to monitor the actual values on a good scanner, this is pretty dang cheap if it solves the problem.

I went and disconnected the battery again. The code actually does go out, then comes back on after two seconds or so. I also got a flashlight on the assembly in question, and there appears to be oil on the outside of it, whereas other components in the area do not have any oil on them.

I wonder if I should order the entire assembly, but also the O ring and gaskets. I could take mine off, replace the O ring and gaskets, reattach, and see if it disappears. If not, I have the new assembly at the ready.

How about clean the assembly thoroughly with brake cleaner then run it to see if and where the source of the leakage is? (the rubber gaskets DO tend to start seeping after 100k+ miles)


You could do it either way....... I just hate to see someone spend a lot of money on a guess, that might not solve the problem.

I've replaced several lousy oil filters to fix this type of code, more than I've ever had to replace VTEC valves.
(Of course the driver goes to Wallyworld or Jizzylube or Freds automart for their next oil change--again.)