K1600GT Hard Starting

[aggieengineer]

Recently my 2016 K1600GT has been exhibiting start problems. The starter will spin the engine rapidly, and it will fire briefly and die. As many as six attempts have been required on occasion.

Here are the details:

The battery is new and maintains over 12V during start.

Gas is fresh, ethanol-free, and is used in my Hexhead without problem.

Problem has occurred during warm temperatures as well as cool. 

Bike has about 11,000 miles on the odometer, plugs are original.

Once started, the bike runs flawlessly.

 

The GS-911 reveals no stored fault codes. Fuel pump pressure is normal, and I successfully ran tests for the tank vent valve, injector actuation, throttle valve servo, and oxygen sensor heating. 

The only value I am unfamiliar with is "Valve for idle forward control" which is showing 199%. Idle air control perhaps?

 

I'm going to try another cold start today while logging the BMSX functions. Of course, it will probably fire up instantly!

 

If anyone has dealt with this problem and can offer any insight, it would be most appreciated. 

[aggieengineer]

This morning I had another crack at it and recorded a few values. It took four attempts to get it started, which finally occurs at line 40. 

log 2019-12-05.csv

[TEWKS]

Long shot but isn't the first valve check on the K16 due around 11k?  Or, am I confusing that number with the cost of the job!  

 

Edit...looked it up, 18 thousand miles. I'm slipping I guess, usually I'll remember useless information like that. 

[MikeB60]

Mine has done something similar in the past.  Hasn't acted up since the I completed the 36000 mile service last year but not sure if that's relevant. Mine was always during a cold start but always started after a few attempts. I'll run some logs and post to compare this weekend.  

[aggieengineer]

After resetting adaptations on the idle control valve to 0%, I got four perfect cold starts. On the fifth, it was back to it's old ways. Temperature was 58F. The GS-911 is still showing the valve at 0%.

The guys at Hexcode are working on a software modification for this setting, but I'm not sure what the effect will be. 

I've retrieved all the software versions from the motorcycle's computer, and will stop by the dealer today and compare with what is current. 

[MikeB60]

I still need to run some logs on mine, got tied up this weekend with other crap.  Haven't started mine in a month, it will be interesting to see if it acts up, that's when I have seen the issue in the past.  

[Beech]

This problem occurred in S bikes around 2015 models, some R bikes also. You are not alone. A service manager provided what seemed to be a bogus solution but I tried it. Turn off the ignition and wait ten seconds or so each time it failed to start. (I had gotten up to 5 failures before it would start). After a few days of this and the number of failed to start events diminishing, I got to the point it would start right up. After three months it started with the failure routine again. Did the same "bad bike" thing of turning it off and waiting. This session cured the problem for years. 

[aggieengineer]

Thanks for the suggestion. I'll give it a try. Went out for a ride a bit ago, and it fired right up. Dealer was no help in determining if my BMSX firmware version (004.000.000) was current. 

[Dennis Andress]

Washington's version of "cold" is closer to 40° then high 50's, but my S1000XR did this when I first brought it home. It stopped after I picked up the habit of turning the ignition on and waiting 10-15 seconds and then pushing the starter button without touching the throttle.

[Calvin (no socks)]

Possibility of loss of fuel pressure. If it happens frequently, test it by cycling key on/ key off. Let set 1 minute... key on, key off. Let set one minute and observe how it starts. Then we will know which direction to go. Next step would be to monitor fuel pressure. Mine does it occasionally after setting for a month or two while I am riding other steeds. 

[aggieengineer]

Good idea. But I've monitored the fuel pressure and it remains steady at about 4500 mbar whenever the ignition is on. 

I read about a possible software update on the BMW MOA website forum. None of the local dealers seem to be aware of it, but connecting to their computer should reveal any out-of-date software on the bike. 

I'll probably do that after the holidays. 

My question is, what has changed in the last few thousand miles to cause this?

[Bprimm]

Since a new battery is mentioned I would suggest a throttle position re-learn could be needed.

 

 

[aggieengineer]

Certainly worth a try. Will give it a shot tomorrow. Thanks for the suggestion. 

[Calvin (no socks)]

In the auto business have seen some gummy/corroded  throttle plates on fly by wire vehicles. Throttle stuck shut and would not start/slow to respond on start-up.... Is throttle above 4%?