My 02 Heritage is having issues with it backfiring out of the throttle body. I talked to a HD Tech and he suggested intake seals. I replaced those yesterday and I'm still having the same issue. I'm at a complete loss as to what the problem is. I'm thinking maybe one of the sensors is bad/going bad?

 

Any codes?

Are the speedo and turn signals working properly. A bad speed sensor will cause backfiring and stalling..

 

I have to double check the codes, but last night I went to check and nothing came up. But I'm also not sure that I was doing it correctly. I will look in my book when I get home tonight to be 100% sure.

I'll check the signals, not sure about the speedo as the bike will barely go down the road. It seems the more I rev it, the more it backfires out the throttle body.

 

On the EFI's a bad speed sensor can cause all those issues. A couple friends had them go on an 01 and 02.. It was a quick replace.

 

So the blinkers work fine. The speedo is a bit iffy. It'll show 5-10mph when I'm barely moving. It also takes forever for it to hit zero on a dead stop, sometimes it doesn't show zero but 1 or 2mph at a dead stop. You still think its the speed sensor?

 

Found out that it might be the MAP sensor. We unplugged it and it instantly did a 180 and idled much smoother, just couldn't get power to it for obvious reasons. Just strange that it wasn't throwing codes.

 

On the blinkers....They will work fine, but they won't cancel, or they will cancel at weird times because if it is the speed sensor they will get goofed up.

But.. Sounds like you may have found it.