Engine dies when hot, slow moving, uphill, at elevation (KrZy8)

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Last year, starting at NAFO, my bike was running weird. It would idle fine, but when accelerating from a stop, it developed a noticeable 'stumble.'

At Tech Day before EOM, we (FYB), that is) swapped out the plugs and performed a TBS, thinking that would cure it.

At EOM, the stumble was so damn bad that I had to rev to aboot 4000 RPM and abuse the clutch to get going. But, I got 'er home.

Turned out to be the MAP sensor (or whatever it's called on the FJR). RaYzerman knew what it was because it had been accidentally knocked off during a valve check or something a while back. He and 'fitter happened to be passing through so they swapped it out and it's running good as ever once again.

 
Did you fix it? I saw a PM from you, but now when I went to look for that PM - it has disappeared??

In my case it was the Intake Air Pressure Sensor.

Or at least that was the last thing I replaced before it stopped shutting off like that...

EDIT - It never threw any codes. As another forum member explained to me, he had a similar issue, which was resolved by the Intake Air pressure sensor. I think he mentioned he didn't always see the error code either, but in my case I never saw that error code.

 
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OK, an update. Finally home and not stuck in a KOA campground. Tools abound. Good stuff.

Ran diagnostics. How nice IS it that a Gen2 can reveal codes without an expensive Yammie part? Priceless.

Here we go.

  1. Ambient air temp displayed 115F
  2. Code 1 - Throttle Angle - 0 throttle read 20 spec 15 -17. OOT (out of tolerance)
  3. Code 3 - intake air pressure - SAT
  4. Code 5 - intake air temp = 136F
  5. Code 6 - coolant temp = 181F
  6. Code 7 - vehicle speed pulse = SAT
  7. Code 8 - lean angle sensor = 0.6 spec 0.4-1.1 upright - SAT
  8. Code 9 - Fuel System Voltage = 10.8 vdc spec ~12 vdc - OOT (battery volts = 12.5)
  9. Code 20 - sidestand = SAT
  10. Code 21 - gear position switch = SAT
  11. Code 60 - EEPROM fault code = 00 spec 00
  12. Code 61 - malfunction history code = 12, 14, 21,22
  13. Code 62 - # of error codes = 4 (correct, see #12 above)
Actuator Codes-

  1. 30 - cylinders 1-4 ignition - SAT
  2. 31 - cylinders 2-3 ignition - SAT
  3. 36 - injector 1 - SAT
  4. 37 - injector 2 - not tested. Hot and don't need to squirt gas into all cylinders.
  5. 38 - injector 3 - same as above
  6. 39- injector 4 - same as above
  7. 48 - air induction system - REMOVED - N/A
  8. 50 - fuel pump relay - SAT
  9. 51 - radiator fan relay - SAT
  10. 52 - headlight relay - SAT
  11. 57 - grip warmer (for sissies only) - NA
I cleared the codes..

Code 9 and 61 revealed. Not worried about 61. Probably a battery replacement or lifting battery leads for maintenance. 9 though...

Low voltage to fuel pump. And this was with the 2013 fuel tank and pump. Consider the conditions:

  1. Hot - reduced alternator output
  2. Hot - fuel pump efficiency reduced, drawing extra current, resultant voltage drop
Next Steps?

  1. Beats me.
  2. Ask fjrforum experts for help
  3. For goodness sake, look at schematic.. what feeds volts to fuel pump? What could be wrong?
  4. Take bike on day off (next Sunday) on a hot day (no problem there, 102F) on a slow uphill.. Can Do! Try to replicate failure.
  5. Wonder about the TPS? Not horribly bad but then again..
Assumptions At This Point

  1. Problem is not OEM fuel pump. Recall this testing done with a 2013 low mile fuel pump..
That's all I got for now..

More overtime tomorrow.

Good to be home. 1R20 can kiss my ass.

JSNS!

..and for the 5th edit!

Thank You to Ionbeam for the great write up on error codes and the entire forum for technical brilliance. Excepting me, of course. I'm not that brilliant.
rofl.gif


 
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I don't like the look of the voltage - seems that you may not be putting the electrons back as fast as you are taking them out running under those conditions. Did you ever hook up an inline ammeter to see whether you were in a net charging or discharging situation when it was misbehaving??

Can't comment on the codes other than 14. Read the following thread and take a few minutes to pop off the hose to the MAP sensor and see if it is filled with goo. The engine certainly ran horribly until I cleaned it out.

https://www.fjrforum.com/forum//index.php/topic/170314-fault-code-14-gen-ii-solved/

 
I don't like the look of the voltage - seems that you may not be putting the electrons back as fast as you are taking them out running under those conditions. Did you ever hook up an inline ammeter to see whether you were in a net charging or discharging situation when it was misbehaving??
Can't comment on the codes other than 14. Read the following thread and take a few minutes to pop off the hose to the MAP sensor and see if it is filled with goo. The engine certainly ran horribly until I cleaned it out.

https://www.fjrforum.com/forum//index.php/topic/170314-fault-code-14-gen-ii-solved/
The ammeter will be next - although the charging circuit, as monitored by a real dmm, shows as very healthy. I see 14.2, 14.1 with minimum load and 13.9 solid with 90 watt jacket, heated gloves, ClearWater lights on max, aux fuel pump on.

MAP sensor goo? Will check that too.

 
I mentioned the ammeter again because of the low indicated voltage on the fuel system. Battery voltage of 12.5 is still pretty low.

The goo in the atmospheric pressure sensor was in the line near the sensor, not in the sensor itself.

 
I mentioned the ammeter again because of the low indicated voltage on the fuel system. Battery voltage of 12.5 is still pretty low.
..and curiously enough, that's the lowest I've seen it at rest. The battery is ~3 months old. Normally I see 12.7 - 13.2. But it was HOT, 115F indicated on FJR temp gauge.

 
Silly question, have you switched your multi-meter over to AC with the engine running? The regulator/rectifier may be new(ish), but is it putting out clean DC, especially when hot?

Brodie

🙂

 
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OK then.

It's not the fuel pump. Naomi's tank and pump (2013 with 12k miles) are on KrZy8 and I was able replicate the problem. Nice warm day, found some isolated hill areas in Atascadero CA, put her in first gear and pretended I was in a line of cars to see Yosemite.

After about 40 minutes, temperature indication 96F, both fans running, I noticed the volts, as read by a cheap dmm connected directly to battery, dropping. And I mean fast. From a normal 14.0/14.2 to 12.5/12.1. Now I am worried about getting back home.

But good! I have AAA if needed and I've replicated the problem using a new-ish fuel pump.

Then the neurons fire. Hey, at Yosemite, you stopped, pulled the key. Next ignition cycle all was good.

So let's not wait.

Key pulled.

10 seconds later, fire KrZy8 up and YES! 14.5 volts.

So then, what to think?

I think ol' Ross K maybe right. At Yosemite, something sucked the voltage down to where ignition was having a hard time firing and she required a lot of gas and clutching and RPM until she died.

So then, what's the cause of this high current draw when hot?

I dunno.

Fans? Maybe one fan is failing when hot, drawing a lot of current but below fuse value? I happen to have a spare set of fans..

...then again, should be easy to test on the lift.. get her hot, oh baby, baby.

Then use diagnostic codes to fire the fans... use Extech current meter to watch i draw.

..any other ideas?

In the meantime, I've been looking at Naomi with pandorous eyes. <new word!>

 
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Seems to me that you replaced the fans when you swapped in the replacement radiator?? Manually spin them to see if the bearings are shot - pretty common for cheap economically priced electric fans. Simple resistance reading or current draw while powered could quickly confirm (or eliminate) the fans as the issue. If the voltage drop is exactly coincident with the fans coming on, it seems pretty likely that is the issue although I suppose there could be a problem with the fan relay itself.

In any case, I still think that the poor running is likely to be a function of low voltage rather than low voltage AND poor running both being the result of something else. While 12 V is sufficient to run the ECU, spark and injectors, there is nothing to confirm that there is this much voltage where it needs to be.

Did you check the hose coming from the MAP sensor?

 
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Seems to me that you replaced the fans when you swapped in the replacement radiator?? Manually spin them to see if the bearings are shot - pretty common for cheap economically priced electric fans. Simple resistance reading or current draw while powered could quickly confirm (or eliminate) the fans as the issue. If the voltage drop is exactly coincident with the fans coming on, it seems pretty likely that is the issue although I suppose there could be a problem with the fan relay itself.
In any case, I still think that the poor running is likely to be a function of low voltage rather than low voltage AND poor running both being the result of something else. While 12 V is sufficient to run the ECU, spark and injectors, there is nothing to confirm that there is this much voltage where it needs to be.

Did you check the hose coming from the MAP sensor?
Ross, both fans rotate nice and smooth by hand. Yes, I used the newer set of fans that I have; they are currently installed. Fan relay? I thought of that too. I have a spare.. Next time tupperware is off, new fan relay and Brodie ignition relay.

Low volts... IIRC, at ~9 vdc she was running pretty darn bad - from another epic troubleshooting adventure... :whistle:

 
Nice hot day today. KrZy8 in an oven called a trailer.

  1. Fired up, let idle 14.1 vdc at idle. No fans
  2. Fan cycle 1, both fans on and sound good, 13.8 vdc
  3. Fan cycle 2, both fans on and sound good, 13.8 vdc
  4. Note 1 - about 30 VAC as read on cheap dmm. This could explain the radar detector voltage fluctuations.. the same RD on a dl650 is rock solid...
  5. ​Note 2 - fans come on at bar 8.
  6. Fan cycle 3, both fans on and sound good, 13.8 vdc
  7. Fan cycle 4, both fans on and sound good, 12.2 VDC
  8. Key off, fans off, standing battery vdc 12.8, 12.9 vdc
  9. Key on, engine running, both fans on, 13.4 vdc
  10. About 60 seconds later, 12.5, .4, .3, .2 vdc
End of test.

Hmm. I don't think it's fans either. Something electrical is getting hot and giving up the ghost.

  1. Wiggled the leads at the RR, no change. Whoa, the RR is HOT!
  2. Found my old post.. 11.2 volts is where an FJR starts to not run good.
No time to do more troubleshooting. Work calls.

Any ideas?

 
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The one bit of information you need is current from the RR.

Ideally use a clip-on ammeter on the positive wire from the RR (at the RR).

Repeat the test you carried out above and establish if the current remains about the same, with the fans running.

If the current stays (about) the same but the voltage drops, then it looks like it's the RR.

 
Finally broke down and bought a 12 dollar voltmeter..

This is after I replaced both the stator which looked OK and RR with one 'I just happened to have laying around'.

Later, I'll run KrZy8 until both fans come on with all circuits activated (fans, aux light, aux fuel pp, brakes, SOS blinkers, windshield moving up and down)

ps If the video seems jiggly, you ain't been getting laid enough...

https://vimeo.com/226973042

 
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I've been watching the progress of this thread since YFO, Don, and it is finally clear where the problem lies (or is that "lays"?).

Take a step back and you'll realize that the problem is the diagnostician. See post #35 for the groundless conclusion about why a ham handed video shoot looks "jiggly". The far more probable reason THAT video might not look jiggly to you is that you likely viewed it after riding the HD on the dirt access road. So the reason it didn't look jiggly to you isn't because you and the Ms. have been sheet rassling a lot lately, but because your old teeth, eyes and joints were still rattling at a sympathetic frequency.

 
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