Hi.

I have a 2006 Fatboy FLSTFI (88CUI stock) that are WITHOUT O2 sensors.

I have a SE Stage 3 kit (heads, 95CUI, cams, exhaust and air filter) and when it, a couple of days ago, was dyno´d, the tuner used a map with O2 sensor exhaust.

It runs very well now so I'm very happy BUT........ now the engine error lamp turns on and the error codes says no response from O2 sensors.

I guess the ECM, according to the wiring diagram, has input pins for the sensors even they aren't wired.




Is it possible to install resistors and what resistance is needed?

Also I´m not exactly sure if its the 5V sensor ground or the 5V sensor power that has to be in the other end of the resistor.




I'm looking forward to receive advice from the H-D professors in this forum.

 

What TUNER is on your Bike for the ECM? What ever MAP he used probably set the O2 sensor option on. You shouldn't have to trick it to think there are O2 sensors.


Mike

 

I'm confused (not unusual really)........ not sure what you mean by, "the tuner used a map with O2 sensor exhaust."

HD ECMs without O2 sensors, use Open Loop maps...

HD ECMs with O2 sensors, currently use narrow band O2 sensors. They run MAPs with a portion that is Closed Loop and a portion that is Open Loop. If the ECM reads a problem with one of the OEM O2 sensors, it will go into open loop operation.

If you had your bike professionally dyno tuned, he may have started with a MAP for a bike with OEM O2 sensors. It's possible he forgot your bike doesn't use O2 sensors, and/or forgot to turn off closed loop operation on the map when he was done.

I know with a PowerVision tuner, you can go to quick tune and turn off closed loop operation... problem solved

Get the guy you paid to tune your bike to give you the proper map... don't try to work around his forgetfulness, laziness, or incompetence...

Let us know how it turns out...

 

Mike and Hattitude......

I understand what you´re saying but here´s the deal.
My bike is tuned with my SESPT.
My tuner, who is very skilled, by mistake started out with a MAP that had a O2-equpped exhaust.
Now my ECM thinks it´s supposed to receive signal from sensors.

My bike runs like a dream so I don´t want to start all over (My tuner will do this for free as the MAP was his mistake)
However........ If I trick the ECM now..... I´ll be able to, over winter, to mount bungs AND O2 sensors.

 

Interesting.... I was unaware that the SESPT can't just take any map and turn on/off closed loop.

Even if he redoes the map by starting with a non-O2 map, if your bike runs great with your current map, all he should have to do is copy all the cells from the map you have and put them in the non-O2 map and it should run the exact same but without the check engine lights....

Depending on the limitations of the SESPT and his computer skills, it should just be a computer exercise and then a reflash to your ECM...

You'd then have a MAP for Closed Loop w/O2 sensors and a MAP for Open Loop operation

If you are going to add O2 bungs and O2 sensors over the winter... I'd just ride with the check engine light until then...

 

I asked a specific question, but got no useable answers, just a lot of opinions of this and that.

Well...... I sorted it out myself. And it´s working. If anyone cares to know how to do, write to me and I will be at your service.

 

Or you could just post it on the open forum to help out other people searching for answers!!

 

I have a 2006 Dyna, international version, originally with plugs instead of O2-sensors, (and now with PCV and Autotune with its broadband sensors installed). I had hesitative throttle response at warm engine, but after mounting Dynojet´s resistors on the ends of the cables attatched to the ECM, the bike ran considerably better. These were 1 ohm resistors. I assume they will also help against an ECM looking for these sensors and alarming about that they are missing.