2012 FLHTP that has had a sidecar attached almost since new and only goes out on snow day funeral escorts. 20K miles. All original and stock.
Last Friday on a return trip the bike started running rough and trying to cut out. Sat over the weekend and then Monday seemed fine until fully warmed up and started trying to cut out and died at a couple of stops at intersections. Returned to shop and cooled down then restarted with black fuel smoke coming out of the exhaust. Checked plugs and both were gas fouled. There are no trouble codes showing and I checked the wires to the MAP sensor as we've seen those fray before, no issue. Noticed the air filter was fairly black but not dusty.
This seems to have come on in a short time out of nowhere so I'm open to ideas on where else to look.
Engine temp sensor? Adding fuel because it thinks it's hot. Did it drop a cylinder too?
I thought about the ET sensor as we have seen them fail on earlier models. Wouldn't a failing ET sensor trigger a code?
Quote from: fleetmechanic on April 21, 2021, 07:08:29 PM
I thought about the ET sensor as we have seen them fail on earlier models. Wouldn't a failing ET sensor trigger a code?
No it won't.
I don't think the ETS has triggered codes since 1998. Something to do with the fact it was piggybacked on the CPS engine light warning that would come on with a simple engine kick back on a hot start. I was told they did away with the CPS warning because it was easily triggered and it took the ETS with it.
A good indicator I found was rough running and initially clearing up with speed increase. Kicking and bucking, back fires, over fueling. Shut it off and 20 minutes later it's OK for a few minutes. Once heat soaked the good running period shortens.
I would also verify that the IAC functions correctly. Remove the IAC to clean the pintle and the hole of the seat, then check for proper movement of the pintle when reinstalled. Incorrect movement of the pintle caused by a defunct pintle drive of the IAC motor renders a correct metering if injected fuel impossible in the total rpm regime.
Armin.
Quote from: Armin on April 22, 2021, 03:03:01 AM
I would also verify that the IAC functions correctly. Remove the IAC to clean the pintle and the hole of the seat, then check for proper movement of the pintle when reinstalled. Incorrect movement of the pintle caused by a defunct pintle drive of the IAC motor renders a correct metering if injected fuel impossible in the total rpm regime.
Armin.
Hate to rain on your parade mate but there is no IAC on the TBW (throttle by wire) bikes.
Sorry Scotty, my mistake. Let's hope that he finds a cure to the problem anyway.
Armin.
A defective ET would cause such a problem Then again so would a malfunction injector MAP and IAT. Were both Plugs fuel fouled?
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+2 on the engine temperature sensor/wiring. If the photo posted this is a snap shot from my Power Vision log during the failure.
My bike also had about 20K miles and had your exact symptoms. At first I thought it was the engine temperature sensor after checking the plug and for possible wiring issues. I replaced the sensor and all was good for over 100 miles. When the fault happened again I found that one of the wires had broken about two inches from the sensor plug and the ends would touch each other enough for the bike to run okay until it didn't. The wire was broken inside of the wire insulation and the insulation was still okay.
I bought the terminals 72484-08 and the wire seals 72486-08 from the dealer and spliced in a new short piece of 20 gauge wire to fix the broken wire. Please note these part numbers are for my 2014 Dyna and your parts may be different. I also only replaced the one broken wire but now have spares.
In the photo you can see that the sensor reading would drop to an indicated 50F and was obviously causing the bike to run very rich when it did. The red line on the first graph is the ET sensor readout. Hope you find the issue.
Regards,
Mark
P.S. Intermittent failures can be a bitch to trace and repair. I keep my Power Vision permanently on my bike and the ability to log the sensors probably saved me hours of my diagnostic time and $$ of suspected (?) parts.
Both plugs were fouled so I'm going to try a new ET sensor. I'll also check the wires.
Update: The wires were ok for voltage and proper ground(not to each other) , the resistance of the old sensor was about 1/3 lower than the new one so I'll replace the sensor. Can't return electrical parts anyway.
2nd update: Let it run in place in the shop for about 15 minutes to fully warm up then rode it across the city on the highway and back on surface streets. Never missed a beat. I'll look at the plugs tomorrow when it cools down.
Both plugs nice and light brown now. Looks like ET sensor was the problem.
:up: It's too bad the ETS doesn't throw a code. It's such a common problem. Maybe the MOCO likes getting some extra door rate time from those that have a problem and can't find a pathway to it.
It can throw a code depending on how it fails. But if it's bad and still reading somewhere within the operating range, it won't.
Quote from: Coyote on April 23, 2021, 09:34:21 AM
It can throw a code depending on how it fails. But if it's bad and still reading somewhere within the operating range, it won't.
Looks like that's what we had. The old sensor still was within the limits of the resistance test but was a lower reading than the new one by about a third.
Seems to me they had a bad run on sensors in 2012. My buddy had one and I remember others posting here with them. I remember my buddy's bike we were tuning and stumped why it ran like crap and finally saw the temp data and on a warmed up engine it was 70 degrees.
The colder the weather the farther the bike ran until acting up. It all makes sense now.
It was an easy guess for me because I have had it happen before and more than once. :crook:
Thanks for all the responses.
Quote from: kd on April 23, 2021, 02:30:02 PM
It was an easy guess for me because I have had it happen before and more than once. :crook:
me too.
My bike for what ever reason will need the engine temp sensor changed in it every 2- 3 years. :nix:
I can tell by the way it will start running when it needs a new one. Put a new ET sensor in it...and it's back to running great again.
I have wondered if there is some other component in the circuit that changes it's resistance or something to effect the life span of these engine temp sensors. :scratch: