Idle drops after warm up

[Ridiments101]

Hi all, new here and like what I'm seeing, hoping for some help. Having an idle/stall issue. 2014 heritage 103 with only 11000 miles, stage 1 air and vance&hines bigshots,FP3 tuner. Never a problem till now.  Bike starts right up, idle around 1300 rpm then as it warms up it begins to slow, like normal. The other day after only about 1 mile, I let off the throttle, pulled in the clutch to roll to a stop and idle drops to about 700rpm's (normal is usually around 1000). next stop it does the same then stalls. Starts right up, rides strong as usual but every time I let off the throttle the idle does the same. Sometimes it stalls, others it recuperates. I've read about the idle air control valve in the throttle body and cleaned it (though it was relatively spotless) with no change, Checked plugs, there good, re-flashed both original tune and fp3 tune, nothing. I'm thinking sensors (idle control, engine temp, speed etc..) Even thought of throwing some seafoam in there. Any help is greatly appreciated. oh yeah, I was looking at the FP3 sensor readings today after cleaning the throttle body and noticed it started acting up when the Temperature hit around 160 (that's what leading me to temp sensor). 

[slodsm]

Can you read your TPMS with the engine off ignition on with an FP3? Check it with the engine warm and work the throttle up and down and see if the percentage increases/decreases incrementally or jumps/spikes.


I had a similar issue with an 07 (exactly the same actually) and I got tired of cleaning and looking etc. I changed IACV and TPS for about 65 bucks and an hour of my time and the problem is fixed. I don't know which it was and never got an engine code but I had the tank off for some stereo installation so I figured why not, I'm already halfway there. Problem has never returned although like you, my IACV wasn't dirty and my TPS values seemed to react normally to input.

[Ridiments101]

Hey slodsm, I'll try that today. Good thing sensors are relatively cheap. I'll update so maybe it will help others. Thanks

[Boe Cole]

intake leaking???

[kd]

intake leaking???

That has been my thought all along. Probably less trouble to change sensors before tearing into the intake but a "spray" test on the seals before ordering or buying the parts might be a good idea.

[Ridiments101]

Sounds like a plan. I'll spray test tomorrow.  Changed the engine temperature sensor ($38), no luck. I guess I  was Just hoping since it happens after I ride a few minutes and begins warming up it may not send proper signal. Harley parts guy was really no help. He was basically trying to get me to bring it into the shop. $90 an hour is crazy.  He did say maybe fuel filter or crank positioning sensor.  Frustrated,  the weather here in Florida has been perfect and I'm grounded.

[kd]

Well now you have a spare engine temperature sensor.     

[rigidthumper]

I saw this issue a bunch on 2007 TCs, had a run of bad Vehicle Speed Sensors, and the ECM relies on the VSS info to activate the IAC motor for smooth transitions to/from idle.
Haven't seen it since, but it is a possibility, and not horribly expensive ( 74402-05B, ~$54).

[Ridiments101]

Dam, why can't it just throw a code. I've heard speed sensor also. Dealer is  closed today and it raining. Looks like changing one sensor at a time seems to be what guys are doing. Hoping it not an intake leak. I was told intake leaks usually will stay idling high. Not sure. All the feedback has been great.

[BVHOG]

Temp sensor will default to 160 when they are bad, do yourself a huge favor and pull that FP3 off the bike and get it tuned!!!!!  It is likely the issue.

[Ridiments101]

OK, did the spray test, nothing. Checked wiring for lose or broken connection, nothing. Flashed original map and removed fp3, nothing. Ran the bikes diagnostics and finally gave back a code p1632, odometer learning up. So now I'm going for the speed sensor  ($65 not too bad) mentioned earlier. Hope this works

[Ridiments101]

Yes, the speed sensor worked. 1st 2 miles seemed rough but didn't stall then all of the sudden it smoothened out. I guess the ECM needs to learn it. I took it for a short 10 mile run and ran like a champ. Hope this helps some one else if they have this issue. Thanks all for the replies