Engine Trouble Warning Light during extended tour

[twinfan]

Greetings,
 
I just finished a 3600 mile tour of several western states and experienced a dozen or so transient engine trouble warning lights over multiple days.  The bike is an '06 with roughly 61K miles and all known recalls completed.  It's been flawless other than the occasional fast starter hiccup.  I did not look at the diagnostics until I returned home.
 
I could not really establish a pattern but here are what I think were the relevant circumstances:

• Battery over four years old but spun the engine just fine
  
• Engine at operating temperature
  
• Ambient temperatures were quite warm, mid-80s to over 100
  
• Engine trouble warning light came on only at freeway speeds with light throttle
  
• Closing and reopening the throttle would typically clear the fault, sometimes immediately and sometimes after a few tries
  
• Instantaneous fuel mileage dropped when light was on
  
• There was a delay in response when opening the throttle from closed when the light was on
  
• Hoped it was bad fuel but it reoccurred after multiple fill-ups
  
• Some days the fault never occurred
  

 
When I returned home I studied the FSM and ran the diagnostics.  I found these faults stored:

• 13 - Intake air pressure sensor (open or short circuit)
  
• 21 - Coolant temperature sensor
  
• 32 - 02 sensor (compensation stuck to lower limit)
  

I do not know if all of these occurred during the trip as I've never looked at the diagnostic screen before.  I'm also not sure if they are presented in numerical or chronological order.  If it happens again I'll know how to check the fault code immediately.
 
I ran the entire list of diagnostic codes:

• D01 - TPS sensor operated smoothly and showed values from 16 to 102 (could possibly use minor recalibration but seems unrelated to the faults)
  
• D03 - Intake air pressure sensor showed a value of 99.  The voltage at the two terminals was 3.97V and it dropped when I placed an oral vacuum on the sensor.  This is within spec.  This seems at odds with the open or short circuit description of the fault.  
  
• Though I did not get fault #14 I checked the intake air pressure hoses and they were clear.
  
• All the other sensors and actuator responses were normal.  There is no specific test for the O2 sensor.  All connections looked good.
  

 
A number of searches yielded the TPS as the most often-mentioned problem, but still not common.  Any thoughts on where to look next or what to replace first?  I installed a new battery and I may need to just button it up and ride until it happens again.
 
Many thanks,
Tom

 

[RossKean]

Do you have a Power Commander?  I had one on my '07 and I would sometimes run into an error.  Can't remember which one.  Never happened again after I removed the PC.

(Might have been the O2 sensor one...)

 

[twinfan]

No, bone stock.  Seems sensor-related as closing and opening the throttle would generally clear the fault.  I don't think a bad wire or connector would do that.

 

[RossKean]

Well, clear the fault history and keep an eye on it.  Hopefully not "spider" related.  (I mentioned the Power Commander because it produced occasional error codes that didn't result in any serious running problems.)

I assume you haven't had symptoms of grounding issues?

 

[twinfan]

Fault history cleared.  I've never had any grounding issues and the local dealer performed the ground wire recall work a few years back.  

 

[RossKean]

Fault history cleared.  I've never had any grounding issues and the local dealer performed the ground wire recall work a few years back.  

Only one of the problematic "spiders" (S4) is dealt with by the recall.  There are at least two others that have caused issues for a number of people plus at least one non-spider connector that has caused similar symptoms.  I had the recall done on my '07 but had two separate issues that I was able to find and fix myself - one spider by the glovebox (S6) and a non-spider connector in the same general region.  I don't believe that either of these caused a error fault.

This thread may be worth a look if you continue to have issues that could be electrical.  (Doesn't sound like it unless you are having oddities like both signal indicators on, high beam indicator on, non-functioning windshield/glovebox etc.) It includes a "roadmap" of the Gen II spiders among other information and deals with a non-spider problem.

Itsy Bitsy Spider? - Technical/Mechanical Problems - FJRForum

Note:  I have had some random fault codes show up upon a couple of occasions.  Sometimes can happen with a failed start with a depleted battery.  Clear them and they go away and don't return.

 

[twinfan]

Thanks, I thought the recall fully solved grounding problems. I’ll read up on this. I’m still thinking it’s a failing sensor somewhere. 

 

[BigOgre]

Re. TPS, it doesn't sound like that type of issue but even if I was wrong, I don't believe a failing TPS would trigger the Engine Trouble light.

 

[twinfan]

I agree that it doesn't seem like a TPS issue.  There are, however, fault codes 15 and 16 for the TPS (stuck, open or short circuit) which don't fit my symptoms.

 

[RossKean]

I think the best approach at this point is to clear any faults and see which (if any) reappear and under exactly what circumstances.  You could spend days looking for a problem that doesn't really exist - or at least one that doesn't seem likely to leave you stranded or damage the engine.

 

[twinfan]

Grudgingly, I think this is what I'll do.  The good news is that few fuel injection faults will render the engine unable to run.  

 

[rbentnail]

My '07 will give the engine trouble light under very specific conditions as you describe.  When I'm doing a coastal NC run with the throttle lock applied on very flat ground, running 58-61 mph, very light throttle position, perfectly constant speed.  When the stars are aligned perfectly I can go for 30-45 minutes without ever touching the throttle and never changing speed, it's that flat.  Then whammo!  Engine trouble light.  It's happened every year for years.  A little throttle variance, up or down doesn't matter, and the light goes off.  Same error codes stored as you describe.  I freaked out in 2009 when it first happened but now I just cycle the ignition, clear the codes when I get around to it, and go on my way.  To me, this falls in the "ride more, stress less" catagory.

My detailed S4 Spider Bite and repair thread here -> https://www.fjrowners.com/threads/the-ground-spider-comes-home-to-roost.120578/#post-909154  though you seem to have none of the classic symptoms of a spider bite.

 

[twinfan]

Nice to know my symptoms aren't unique.  Hopefully, this is a one-off.