The plot thickens....

[Blade Guy]

I posted about a month ago an issue on my '18 Heritage Stage IV with the O2 sensor code. Checked with another dealer and they said O2 sensors can indeed throw a code (unlike the dealers head tech that said they don't). So I scheduled an appointment and was told to bring the tuner so that they can verify the tune and make necessary adjustments. This was to take place this Friday. Yesterday went out for a ride and just as I got in the driveway it dropped all power-running on 1 cylinder. Pushed it in the garage and saw in addition to the O2 sensor code (PO154) I also had a P1655 (ACR code). Had it towed to the dealer. Find it curious that 2 things that appear unrelated can happen. Wondering about a grounding issue (under the gas tank -if there are any grounds there). The one reply I got on my original O2 post was there was a grounding issue with the wideband O2 sensors on Stage IV builds. Am guessing the gas tank came off for the build. I guess I'll see what happens....am really pissed.

[justaguy]

What tuner did you use for this bike? SE Street Tuner w/ Auto?

[Karl H.]

O2-Sensors and ACR valves have no common grounds or power supplies

Karl

[Blade Guy]

 Yes it was SE Street Tuner w Auto Tune. The O2 sensors are the wideband sensors.

[HV]

The Grounding Issue is due to " Dirty Grounds "  They recommend that all wide band auto tune units ground directly on the Negative side of the Battery

[Blade Guy]

The paperwork I got with the bike (bought it "used" w 2200 miles on it) states it is auto tuned w the SE Pro Street tuner w wide band O2 sensors. This is probably a dumb question , if the bike is set up for auto tune should the tuner unit be mounted on the bike? My tuner is in the box not on the bike. Thx

[98fxstc]

Tuner is hooked up to the ECM for auto tune.
When tune is complete the cal is flashed to the ECM and tuner is removed.

[Blade Guy]

Thx for the explanation. Any idea if "acr solenoid low" and an O2 sensor code can be tune related?

[HV]

The Auto Tune unit remains on the Bike...just the SE Tuner is removed ..

[Blade Guy]

Well I got the bike back from the dealer yesterday. Turns out the O2 sensor code was due to the wrong tune that the original dealer that built the engine put in it. Now have an updated tune that is correct for wideband O2 sensor/auto tune. The code for the acr's was a $1.50 fix. A bad fuse. Called the operations manager at the dealer I bought it from.... "in a meeting, he'll call you back". Right.....

[HV]

Yes if they forgot to check off the Auto Tune wide back o2  option when flashing the Tune it will be looking for the small o2s not the large wide band units... someone either had no idea what they were doing or had a Brain Fart

[Blade Guy]

I've wondered that too. The master tech that built the engine was adamant that O2 sensors don't throw codes and turn on the check engine light. Made no sense to me which was why after 3 attempts I took it to another dealer (a lot closer to where I live) and they found it right away. The dealer tech that fixed it is their dyno/tune specialist. Thx for your interest and responses.

[Hossamania]

I've wondered that too. The master tech that built the engine was adamant that O2 sensors don't throw codes and turn on the check engine light. Made no sense to me which was why after 3 attempts I took it to another dealer (a lot closer to where I live) and they found it right away. The dealer tech that fixed it is their dyno/tune specialist. Thx for your interest and responses.

Not much of a "master" is he?