Hi Guys,
Thanks in advance for any help. I installed V&H Short Shots on my 2016 iron yesterday and today the check engine light game on with codes P0051 and P0154. My tuner says Rear HO2S low/open and Rear Oxygen sensor high/open. See attached. During the install I replaced the stock gaskets with V&H gaskets and I made it a point not to touch the actual O2 sensors during install. The bike only has 3k miles on it so the sensors should be pretty new. I also checked the plug to make sure no pins are missing and that its plugged in snug. Anyone have experience with these codes right after a header upgrade and anything I'm overlooking? One question I have is should the flange connecting the header tube to the engine be flush? On mine (both front and rear), there is some space. But I feel like I've torqued them down real tight and I'd be concerned about stripping the bolts if someone told me they needed to be even tighter or flush with the engine. Could someone check theirs to see if there is a similar space? Any help would really be appreciated.
Thanks so much,
Phil
Codes Front header showing space between flange and engine. Torqued down pretty tight. Rear header showing space between flange and engine. Torqued down pretty tight.
If it was a leak at the header (like maybe if the gasket didn’t seal right) would the code come on right when I start the bike? Right now after I clear the code, the light comes right back on when I start it.
Make sure you do not have a rear exhaust leak (at the head or O2 sensor) and that the rear O2 sensor is tight in the header pipe.
Loose O2 sensor:
If an O2 sensor is loose, engine performance may be affected. This could also show up as a
slow changing O2 sensor voltage.
• Loose/leaking exhaust:
This can cause a poor ground connection for the sensor or allow fresh air into the exhaust
system. If fresh air enters exhaust system, the O2 sensor will read a lean condition, causing the system to go rich.
Po154 means no activity and po051 means low voltage heater control circuit. Verify voltage to both and if you have scan tool see if O2 sensor responding
Heater control circuit? Is that different than the O2 sensor. I’ll have to look it up in the service manual. Is it safe to say that the sensor is bad at this point? I don’t have a scan tool unfortunately and was thinking of just getting a sensor to eliminate things. (Is my Power Vision tuner able to scan o2 sensor readings?)
Originally Posted by normannewguy
Po154 means no activity and po051 means low voltage heater control circuit. Verify voltage to both and if you have scan tool see if O2 sensor responding
The PowerVision can show you the O2 Sensor voltages in the gauges.
It will start around 5 volts when the engine starts while the warm up enrichment is active, it will start to vary between about 0.1 and 1 volts after the engine warms up.
Setup a gauge from-
Vehicle Advanced signals
Front O2 Sensor Volts
Rear O2 Sensor Volts
I don't believe the PV will show the O2 heater voltages.
The O2 sensor has a heater in it. It uses 12v to heat up the O2 sensor so it can start reading faster. One of the 3 wires coming from O2 sensor is a 12v wire to just warm up o2 sensor faster so it passes emissions
11-18-2018, 05:22 PM
P0051/P0154 after V&H Short Shots; Questions
