New to the forum, hope someone has an answer....this is so frustrating. Have searched high and low for answers after trying multiple fixes.

2007 CRV throwing the dreaded P2646 with Vtec "limp" mode, dash lights, etc.

Have ALREADY:
-Replaced the oil sending unit including both switches and a new gasket screen
-Replaced the other oil screen on the front of the engine. Was gunked up pretty good.

Gave to wife to drive to work and it threw the code AGAIN! Of course I got the screaming call as she was on the freeway in the rain

Possibly next? From research, was considering "cleaning the oil tank"? Apparently there is some junk you can throw in (available at the auto parts store?) to clean it out. Of course then flush and new oil and filter.

Any ideas where to go next?? I am at a loss, tempted to take it to the dealer but I just hate paying them the big $$.

John

 

If you know how to troubleshoot electrical circuits and do some basic testing, I would recommend purchasing a shop manual for your crv. Automanualsource.com has them for $22 as a pdf and is well worth the investment.

We can help you out as you go through the diagnostic tree.

 

P2646 is a circuit fault in the vtec oil pressure switch circuit. It can be switch, connector, wiring, or PCM.

I agree w/ PAH advice. I've added instructions from 03-06 shop manual, but your CRV model year could be slightly different.

Since you have a new vtec pressure switch (?), you should check continuity of wiring/connectors from PCM to vtec oil pressure switch connector. You can do this by disconnecting connector w/ wires at the PCM and vtec pressure switch. Test each wire for continuity. You will need the correct wiring diagram for your car to find the correct wires to test.

If wires check OK, and switch is new, a PCM fault may be the problem.

good luck

 

Thanks for the suggestions guys. I have made an appointment with our local Honda guru to have the wire continuity checked.

Someone else suggested that there is another screen inside the oil pan that may be clogged, could that be the cause?

John

 

Very unlikely, P2646 is electrical circuit fault. A high or low voltage was detected by PCM indicating a fault.

good luck