Hose Orientation for the Auto-Choke circuit

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If you decide to replace the wax motor I have several used ones at hand... free to you except for shipping. Hopefully it's gas. If not, offer is open.
Thanks D.  I appreciate the offer.  It's doesn't seem to be a problem with cold start high idle so probably not a problem with the wax valve.  I assume the richer fuel to air ratio needed for a cold start is done with ECU mapping by simply making the injectors squirt a little more gas.  But does anyone really know how these things work these days.

So how did you come by having some spare wax valves laying around?

 
I doubt this is the problem but anyone know where the hose goes that comes from under the plastic box that the ECU is in and looks like it's coming from the bottom of the ABS modulating valve.  I'll post a photo if I can figure out how to do it. 

 
You can also "Insert image from URL" to have it show up directly.  Just copy the link from Postimages.

I am not sure what that particular hose is - likely a drain??  Any evidence it was ever hooked up to anything?

IMG-9450.jpg


 
the saga continues

I had no problems on my trip to South Dakota.  8 days, 3600 miles, most of it in ID, MT, SD, and WY.  It started and ran perfectly every day.  The morning after I got home it would not start without pumping the throttle and runs horribly. I checked the diag codes again and nothing off there.  I sprayed starter fluid in around the throttle bodies and there is no indication of vacuum leaks around the intake.  It seems to be running too lean.  Next I'm going to pull spark plugs to see if they will give me a hint.

I made the following notes when checking codes.

03  differential pressure, 4 vacuum hoses from the throttle bodies to the sensor, I checked the hoses for leaks, mine says 100 normally and 122 if I unplug the sensor,   I put a vacuum gauge on it and sucked it down to 10" Hg and it read 65

05  Air Intake temp , reads current air temp, -22 when unplugged

06  Coolant temp - current normal is whatever the current temp is, -22 when unplugged. 

All these will throw a code if unplugged in normal "run" mode but the code clears (yellow idiot light turns off" when plugged back in but the code shows up in the history record (diag code 60 and 61) until cleared.

 
I assume this hasn't occurred after the bike has been sitting in the sun for a period of time?

There have been issues with California model FJRs where the charcoal canister gets fuel saturated sitting in the sun and runs horribly until intake air evaporates the fuel.  Note: Just because the bike didn't come from CA, doesn't mean it couldn't be a CA model.

Long shot, I know, but a possibility.

 
I assume this hasn't occurred after the bike has been sitting in the sun for a period of time?

There have been issues with California model FJRs where the charcoal canister gets fuel saturated sitting in the sun and runs horribly until intake air evaporates the fuel.  Note: Just because the bike didn't come from CA, doesn't mean it couldn't be a CA model.

Long shot, I know, but a possibility.
Thanks for the additional comments.  It's not been sitting in the sun much for the most recent occurrence of the problem and it's does not have any CA emissions stuff that I can tell, at least there are no extra hoses on the bottom of the gas tank other than the overflow.  And I finally found the mystery hose shown in my previous post.  It's just a drain hose from the ABS unit.  Part no. 5VS-85828-00-00.  It's part no. 3 on the Electrical -3 fiche.

I pulled the spark plugs and they look good.  But I suppose if I have a dead injector the spark plug might look ok.  

Next is to check gas pump pressure and make sure all the injectors are working then maybe synchronize the carbs. I'm sure it will be an obvious dumb thing when I finally find it but I've double and triple checked all the vacuum hoses and electrical connections so I'm at a complete loss right now.  I was thinking maybe it's a spider bite problem but it looks like the injectors ground back thru the ECU and 2 years ago I soldered the S1 and S4 and S6 including an added 12 ga. ground loop wire from each back to the battery terminal.      

 
Next is to check gas pump pressure and make sure all the injectors are working then maybe synchronize the carbs.
No carbs but I understand what you are saying...

Throttle body synchronization won't hurt but is VERY unlikely to be the problem.  Fuel pressure issues are not common but I suppose it could be possible. Use a flashlight to have a look at the bottom of the tank and the fuel pickup screen to see if there is any garbage in there that might be blocking flow (and could have plugged injectors).  Might be worth getting the injectors serviced and checked for flow and spray pattern.  Keep an eye open for any new fault codes that might crop up.

Note: For a California model, the charcoal cannister is behind the triangle piece below the radiator and there is a drain hose that comes through an additional hole in the bottom of the lower fairing.  Hose could get pushed up and kinked.  Doesn't sound like your issue but could cause serious running problems.

 
how about O2 sensor?  It does not show up on the "diag" list.  I assume it provides info for the control module at least when running closed loop. I assume a FJR runs open loop until it warms up???  Anyone know this??   Maybe I'll unplug it and see it it throws a code.  The only other bit of info that the CPU might use to control fuel mixture is the intake air pressure.  And anyone out there willing to run a diagnostic and tell me what they are getting for the air pressure reading?  It's Diag code 03.  Mine is 99 (at about 200 ft. elevation) and 122 when unplugged.   And I got a reading of 65 when I sucked it sown to 10" Hg vacuum  (about 11,000 ft elev.). 

Does an FJR have a knock sensor?  Usually those are only used to adjust timing. 

 
Does an FJR have a knock sensor?
No knock sensor.

how about O2 sensor?
The FJR will run just fine without an O2 sensor (normally gets unplugged if running a Power commander) but doesn't run well if the O2 sensor is giving the wrong signal.  Might try unplugging the O2 sensor.  I had an issue once when the O2 sensor wires got caught in the timing cover during reassembly.  Wires shorted out and any signal provided was garbage.  Ran very poorly.

 
No knock sensor.

The FJR will run just fine without an O2 sensor (normally gets unplugged if running a Power commander) but doesn't run well if the O2 sensor is giving the wrong signal.  Might try unplugging the O2 sensor.  I had an issue once when the O2 sensor wires got caught in the timing cover during reassembly.  Wires shorted out and any signal provided was garbage.  Ran very poorly.
I'm gradually learning a bit at a time how this system works. According to the Supplementary Service Manual pg. 24, the engine will continue to run in open loop mode if a sensor input is out of range, well for some sensors.  If the lean angle sensor is goes out of range the engine shuts off. 

According to page 26 there are no diagnostic codes for the O2 sensor.  I'm going to unplug it and see if the engine will run right in open loop mode.  

https://www.manualslib.com/manual/802254/Yamaha-Fjr1300-S.html?page=24#manual

If the ECU detects an abnormal signal from a sensor while the motorcycle is being driven, the ECU
illuminates the engine trouble warning light and provides the engine with substitute characteristic
operation instructions that are appropriate for the type of the malfunction.
When an abnormal signal is received from a sensor, the ECU processes the specified values that
are programmed for every sensor, in order to provide the engine with substitute characteristics
operation instructions that enable the engine to continue to operate (or to stop its operation,
depending on circumstances).
The ECU takes fail-safe actions in two ways: one in which the sensor output is set to a prescribed
value, and the other in which the ECU directly operates an actuator. Details on the fail-safe actions
are given in the table below.
Table of substitute characteristic operation co
 
so in the end my problem was low fuel pressure, like only 20 psi.  This was caused by a problem I caused when I pulled apart my fuel pump to repair a broken off the barbed connection where the hose attaches to the pump.  And that happened when my tank took a tumble off the bike because I had it propped up to work on the Rostra cruise control linkage.  The tank was propped up but not connected by the hinged bracket at the rear of the tank because I have Helibars and the front of the tank can not be raised without disconnecting the rear mount.   Next time I'll prop the front of the tank up but not until I reinstall the rear hinge pin.  Also don't take apart your fuel pump unless you pay close attention to how it needs to go back together - DUH!!

 
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