KrZy8 hard starting, intermittent missing

[dcarver]

SHIPPED: 07 2007 YAMAHA FJR1300 FJR 1300 CDI BOX ECU UNIT COMPUTER..arriving next Monday....

 

[beemerdons]

SHIPPED: 07 2007 YAMAHA FJR1300 FJR 1300 CDI BOX ECU UNIT COMPUTER..arriving next Monday....

This shipped on Saturday, did it arrive! JSNS, Wondering!

 

[juniorfjr]

SHIPPED: 07 2007 YAMAHA FJR1300 FJR 1300 CDI BOX ECU UNIT COMPUTER..arriving next Monday....

This shipped on Saturday, did it arrive! JSNS, Wondering!

Needs some blue tape.

 

[dcarver]

KrZy8 is back to old tricks.. this morning hard starting and missing. That's good in a way.

 

[escapefjrtist]

SHIPPED: 07 2007 YAMAHA FJR1300 FJR 1300 CDI BOX ECU UNIT COMPUTER..arriving next Monday....

This shipped on Saturday, did it arrive! JSNS, Wondering!

Needs some blue tape.

...now we're talking!

DC, start riding the GEN III and all your problems will disappear!

--G

 

[RossKean]

DC, start riding the GEN III and all your problems will disappear!

--G

Except for the spongy rear brake pedal!

 

[dcarver]

The saga continues. If my guy can't get it fixed soon I'll be bringing her home so I can molest her myself. Mumbling to myself at this point. Hmmm,

Other weird shit -

1. Ivan has a stand-alone gas tank with onboard pressure regulator. When he cranks the pressure up from 47 psi (oem spec) to about 60 psi, the rpm's pick up and she smooths out. But I would expect that... more pressure = more flow for same pulse duration.
2. Once, for whatever reason, she fired right up and ran perfect. Even for several starts. Just like nothing was wrong. Then, after siting for a day, back to bad behaviors.

So then, what to do? Order parts. Parts ordered:

1. ECU - used
2. Complete throttle body assembly including injectors, TPS, and bodies - used
3. Throttle body wiring sub-harness - used
4. O2 sensor - used

Observations -

1. Won't go into CO mode, diagnostic.. Barbarian mod has been done in 2006 but.. did that harness get replaced?
2. Dribbling fuel into vacuum port improved running
3. Increasing fuel pressure to rail seems to improve running (but wouldn't that be expected?)
4. Plugs running sooty rich all 4
5. All 4 cylinders running poorly

Attack Plan

1. Check ECU connector for loose wires, deformed pins
2. Check ECU connector to see if Barbarian mod has been done
3. Check TB wiring sub-harness for loose wires, pins, etc
4. Substitute, in this order, these parts
   • 
     O2 sensor
   • ECU
   • TB sub harness
   • Throttle body

 

[ionbeam]

Check the wax motor choke control for binding and full closure when hot.

Considering what parts are on order and what you are going to check there isn't much to add at this point.

Plugs running sooty rich: Too much gas, too little air, incomplete combustion. If the plugs get sooty in just a few minutes of running things are wicked rich. Even if you don't add fuel pressure, when first started the choke system is active and running the cold enrichment routine. To read plugs the engine should be run until heat soaked (like at least a 20 minute ride) then without dropping RPMs to idle the key should be shut off. Now pull the plugs and using a magnifying glass give 'em a good look.

ECU: aren't usually intermittent, they either make good decisions all the time or they make bad decisions all the time.

O2 : Essentially out of the picture for this. Simply unplug the sucker to check if it is involved.

Barbarian: If the jumper was installed and it now doesn't work the jumper has come disconnected or the connector isn't seated. I'd guess that it would be hard to only have a couple of pins not connecting and the rest ok. Something has changed.

Complete throttle body: Yes, if you are up to the work it will rule out a whole host of possible issues. This will also rule out the wax motor.

Bung the head pipes and use a 4 channel EGA and actually measure what is going on

You can stuff your probe up the pipes after the cat and still get some idea what's going on. IIRC, CO after the cats should be 1.5% or less; before the cats will be around 2-4% - I'd really have to look that up.

 

[TownsendsFJR1300]

1. "Ivan has a stand-alone gas tank with onboard pressure regulator. When he cranks the pressure up from 47 psi (oem spec) to about 60 psi, the rpm's pick up and she smooths out. But I would expect that... more pressure = more flow for same pulse duration."

What is your fuel rail pressure (with the OEM pump)?

Is there a way to check the actual fuel line from the pump should the inside have collapsed due to ethanol? I've had the innerds of marine fuel line on the boat literally peel off from inside the line and get caught up in another filter..

With what you've posted above, sounds like its definitely a fuel delivery issue

. Is there another FJR, same gen, that you can swap tanks(with pumps) out and see what happens???

 

[dcarver]

Stopped by Hidden Power Cycle Clinic today and we swapped out:

1. ECU
2. Pressure sensor on fuel rail
3. Fuel injector sub-harness

No happiness to be found. Starts hard and runs rough, getting better as it warms up... almost to normal.

Edit -

• also disconnected o2 sensor. No difference or error code either.
• discovered that the Barbarian mod had not been re-done after warranty work. Did the mod and now Co shows in the Diag mode.

Next step is to check cam timing and valve clearances, just to be sure.. then replace the entire throttle body assembly.

 

[RossKean]

No happiness to be found. Starts hard and runs rough, getting better as it warms up... almost to normal.

The above statement suggest that the issue is with the cold-start circuit. Wax motor etc. Has to be the culprit unless you have collapsed or clogged lines somewhere. You have eliminated most everything else.

I suppose a vacuum leak somewhere could be an issue but I assume that you have checked that? You can carefully spray a little WD40 around potential leak spots or, VERY carefully, direct some propane from an unlit torch. Vacuum leaks will give you a change in engine speed when fed a little extra fuel. (Propane is less messy than WD40)

 

[BanjoBoy]

Uhhhh, did anybody check to see if a rodent made his home in the airbox?

Check the wax motor choke control for binding and full closure when hot.
Considering what parts are on order and what you are going to check there isn't much to add at this point.

Plugs running sooty rich: Too much gas, too little air, incomplete combustion. If the plugs get sooty in just a few minutes of running things are wicked rich.

 

[dcarver]

Possible good news!

Ivan called and said KrZy8 has been running GREAT since replacing the throttle bodies with ones I recently purchased from eBay for 80 USD. The new TB's replace the fuel rail, 4 injectors, TPS, manifold pressure sensor and one widget that looks like a regulator but I'm not sure.

Ivan says she fired up immediately upon install and sounds really happy. On cold start this AM, she's a tiger ready to roar.

I'm to see Ivan tomorrow early to verify cruise control is as it should be then he'll button her up.

Oh, the valves were perfect. All in spec.

..fingers crossed!

 

[Panman]

Damm long road on this on Don! How all is good now.

 

[dcarver]

Damm long road on this on Don! How all is good now.

Thanks, K. I'm eager to prove Ivan right tomorrow morning.

..and then to figure out what failed. I have to know.

 

[dcarver]

Stopped by this morning.. KrZy8 is B A C K!

Easy starting, fast throttle response, smooooth....

Will examine throttle bodies over Christmas holiday.

 

[rushes]

I'm kinda curious what the autopsy reveals...

 

[Niehart]

I'm kinda curious what the autopsy reveals...

+1

 

[dcarver]

Well, given the passing of BeemerDon's yesterday or the day before, this sure seems trivial. Nevertheless, KrZy8 is back home and roaring like a lion. I had forgotten how sweet that 08 engine is and just how comfy I have that bike set up for my carcass.

This means I can now start giving Naomi the jewelry she deserves.

Thank you to all who contributed ideas and thoughts and for the encouragement to keep after it and not let KrZy8 become a parts queen.

 

[Surly]

You Rock!