VFR800 2005 Dies when release ignition

The bike starts, but as soon as I let off the ignition switch, it dies. It had started coughing and dying at low speeds, 20-40mph, and would die drifting into a stop, but would usually restart. Now it starts fine sometimes, and other times it will die as soon as I let off the ignition switch.

I thought it might be the fuel pump, based on the startup whine and the cough-die symptoms, but I'm not sure how the pump would work while the ignition is in, then cut off after I release the ignition, maybe I just don't understand how the pump interacts at startup. I can throttle the bike if I keep the starter depressed (I have not done this over and over, just to test), but when I release the switch, there is no pause, it just dies like a shot bird. And then it starts and runs fine other times.

I'll try cleaning the killswitch contacts and poke around the electrics for oddities, but I still keep coming back to fuel pump, maybe the filter. Does anyone have any better ideas, or maybe a correction to my understanding of the troubleshooting?

Much thanks.


- Eric
2005 VFR800

 

My guess is it is ignition not fuel, lack of fuel would not cause it to die instantly, even with fuel injection I would expect it to run for a second or two,I think it is getting power to the ignition back through the starter circuit. Kill switch I'm sure would knock out the coils regardless of the start circuit

 

Thanks, N. I should add that the pump does not always prime when I turn the key to on position. There is a buzzing sound, so might be a loose wire somewhere.

 

Hi Eric and welcome to the MadHouse:welcome:.


When you get a chance please drop by the Introductions thread and say Hi to the rest of the folks on here. PS maybe add a photo or two of your VFR to stop folks raggin on you.

:focus:

You are not the first to arrive on the forum with a troublesome VFR and the symptoms you describe do sound more electrical than fuel flow/supply. If the fuel filter/pump really was badly blocked then it would run like a dog all the time - as once it is gummed up it is hardly going to clear itself. As you suggest there are times when it is still running fine, but on other occasions you cannot hear the fuel pump priming I think you need to focus on the starting and safety interlock circuits.

Even if you are not very familiar with your VFR - at the moment you know a lot more about your bike than we do - stuff which might help us home in on what is(is not) happening. In this instance brevity is not critical so perhaps let us know if this a new/recent problem / and confirm whether or not the bike was running fine before? Did the problem arise after you had any work done on the bike /or possibly crash damage? Are there any MIL codes?

At the moment it sounds like you may have an intermittent break in a wire in the safety interlocks or a faulty component therein. The following diagram shows how the various items interact and where the items are to be found.

http://www.lifford-cooke.com/motorbiking/documents/VFR%20VTEC%20PGM-FI%20Diagram%202002.pdf

I hope this will allow you to test and hopefully locate what is actually causing the bike to misbehave. Do not assume parts will last forever - your bike is now 10 years old and even if it has done very few miles - parts can and do fail. I assume you have checked your battery volts are in good order - and the terminals are clean and tight. It might help if you update your forum profile to include your vehicle specs and a rough location (city/state is fine) that way if you are getting nowhere - post up again and you may find someone else on the forum lives nearby and is willing to swing by and offer advice - especially if you have a well stocked beer fridge.

Good luck - let us know how you get on.




SkiMad

 

No code or other warning. I'm running through elec diag, battery shows good V so I'll start there. I'll get something in the intro section, much thanks for suggesting it. I've been lurking for a couple of years -- yes, years -- just never had much to say. I was hoping loose battery cables, but they're tight and charged up... onward ho.

- Eric

 

Found this thread: http://www.southbayriders.com/forums/threads/5478/

It describes my exact symptoms. I pulled apart the connector box, and it's got some burn issues on the lower left corner. I'm still trying to get it clean, but I think this might be my root cause.

 

And found this recall: http://www.vfrdiscussion.com/forum/index.php/topic/35937-safety-recall/

Probably old-hat news

 

well done eric... those would have been my first suggestions