"Engine may not operate properly. Acceleration may be reduced."

Has anyone seen this error code? I finally got a CEL today after 2 weeks of 1st to 2nd gear "hitches". Now this issue occurs for every gear around 4400-5500RPM. 30% of the time the car will redline, every other time it will hitch for a good 1-3 seconds before it shifts itself. Occurs in D, S, and Paddles.

2009 FWD TL

 

what do you mean by hitches?

 

P2646 : VTEC low pressure oil switch circuit low voltage.

If the car is still under warranty, bring it in to the dealer.

 

The easy thing to check is turn the wheel all the way to the right and look right above the oil filter (that blue thing) if the connector and wires are ok. That is the VTEC oil pressure switch. Next in your list is to check the oil level. If its too low the VTEC will not fire, even if the conditions are right, therefore throwing an engine code. If that is OK and based on previous experiences with VTEC engines, the first thing that goes bad is the Solenoid. It is in the same assembly as the switch (if I recall correctly).

PS. I haven't looked at mine yet, but the VTEC oil pressure switch on this version of the J engine may be next to the intake manifold?

 

It's the oil pressure switch. I had the same code and problem with my car.

 

Example: I shift it to sport mode, Downshift to M1, Hard launch from 1st gear to second, at 5400-5500 RPM the car hitches/jerks/slips/etc. This occurs 1-3 seconds then proceeds to redline before I shift into second gear. The hitches and jerks can be described as the RPMs are redlining, however 5400-5500 is far off from red.

What would I say to the dealer? Could a battery change be a possible fix or would the switch have to go?

 

"I have a check engine light that indicates a problem with the vtec oil pressure switch. the code is P2646"

 

Tell the dealership your car's "check engine" light is on, and let them figure out what is going on.

They have the factory service manual to troubleshoot, diagnose, and fix any error codes that got thrown out by the PCM, provided you don't have aftermarket engine-related mods that can complicate the process.

 

hey i just wanted to know what the problem was or what the dealer said bacause this weekend i had the same problem but i have a 07 tl-s

 

What ended up being the fix to your car as I am having the same problem with my 2005 Acura RL and really need a solution before getting things replaced. They say my rear main seal is bad could this cause that problem?

 

bad rear main seal means that you are dripping oil! Low oil level could cause the issue as VTEC relies on oil pressure to engage properly.