hondagrl12

My check engine light recently came on and after getting it checked, the codes that came up are P2646, P0420, and P0138. They told me that the most important was the first one which has something to do with the Rocker Arm actuater control.

What will it take to fix this, how much am I looking at spending and what do I do next..help appreciated!! Thanks in advance

lazlong

"Rocker Arm actuater control" is a fancy way of saying VTEC oil pressure switch. VTEC adds a little horsepower (hp) around 3000 rpm at wide open throttle (WOT). Oil pressure is one of the ways the ECM/PCM (computer) senses that it's time to hit the VTEC. The ECM/PCM uses an actuator to move to the VTEC lobe on the camshaft which makes an extra valve open up in each cylinder.

P2646 is probably the cause of P0420 (catalytic convertor [cat] efficiency below threshold) which is most likely the cause of P0138 (secondary O2 sensor high voltage). The high voltage in the secondary O2 sensor means the cat isn't doing it's job and it's reading high pollutants. So yes, P2646 is probably the cause.

At the least, you're looking at a couple hours of diagnostic time plus a new oil pressure switch. At the worst you're looking at 6-10 hours diagnostic time plus a new oil pressure switch, cat, and sensor(s) plus several hours labor on replacing those parts. Going rate for diagnostic time around here is $100-150 at the dealer, around $80 at the independents.

*DO NOT drive it until you fix this. If you haven't ruined the cat and sensor already you will shortly. The cat runs $900 at the dealer, $700 at the online dealer (google "OEM honda parts") and the sensor runs $150-ish.

Unless you know your way around a multi-meter, about the only things you can do right now is:
1. make sure you have the correct amount of oil
2. LIGHTLY tap the cat, if it sounds like there's stuff rattling around in there then the cat is already bad
3. If you do drive it, when you stop, see if the cat is glowing red hot. red hot= bad cat