Posting new thread: Too long cranking for Starting

stepaukob

Registered
I keep going through batteries because the bike takes too many cranks to start.

Bike takes at 4 or 5 seconds and then I usually stop cranking. I'll turn the key off (too long cranking), and crank again. Sometimes I'll give it a little throttle which may help but there's a fine line where giving it too much throttle as it will flood it and/or cause a backfire. Then sometimes the bike will burn the fuel dumped into the TBs as you can see and smell the burned fuel.

It will start a "little" better warm but still takes too many cranks. It's frustrating. When it does start, it's starts off a slow idle for a second and will then pick up to a faster idle.

It NEVER starts right up. It ALWAYS takes a number of seconds (which is a long time) and I usually have to shut it down and start cranking again. Too much cranking and I keep going through batteries as I wear them down.

2002
PCII
Stage I turbo but this has happened even before turbo was put on.
Injectors tested.
TPS is within range.
New plugs.
Runs great after starting.
Idles fine after initial hard start.

I may make a video so people can see what I mean.
 
Put some Seafoam in it and take it for a ling ride. Can't hurt.

If that doesn't work - have you ever had the TB's synced ?
 
Maybe take the spark plug connectors out and put some dialectic grease on the contacts. You may not be getting enough juice for an initial spark
 
Someone on another forum pointed out the fuel gauge. If you notice, the first number of cranks the pressure is down. The last crank before starting the pressure is 43 lbs. I tried again this morning and almost every crank the pressure was up and the bike started. One time the pressure dropped so I stopped cranking. Not sure why it's doing this.
 
I unplugged PCII under the tank and plugged original wiring together. Now the fuel gauge is dropping right after initial key on. Similar to what it was doing in the first video. Yesterday about 11 out 12 times pressure stayed up and bike started.

Off to work now. I'll try again tomorrow.


 
No one is answering but I'm posting another video in case someone in the future has a similar problem.

New Video:
Pressure drops but comes back during cranking (sometimes) When this happens the bike fires quickly. Pressure seems to be dependent on starter button being engaged which would seem electrical in nature.

 
I know nothing about motorcycles, but quite a bit about cars. These symptoms with an efi vehicle would almost always be a faulty fuel pump check valve or a fuel pressure regulator. To find out if you have a leaky check valve, you would prime the fuel system before starting by turning the key to the on position without starting and then back off 3 or 4 times before trying to crank.
 
I know nothing about motorcycles, but quite a bit about cars. These symptoms with an efi vehicle would almost always be a faulty fuel pump check valve or a fuel pressure regulator. To find out if you have a leaky check valve, you would prime the fuel system before starting by turning the key to the on position without starting and then back off 3 or 4 times before trying to crank.

I keyed on to pressurize the line and clamped the off the fuel line right after the fuel rail. The pressure held so the check valve in the fuel pump seems to be working.
 
I suppose running an inline check valve between the pump and fuel rail would be an easy fix.

PLZ TELL MORE. im having the same problem, when i go to cut the bike on i here the fuel pump kick on but when it kicks on with a delayed second i her a spray like something is gloging the pump or something so i cut it off then back on a few times then it starts after the battery is almost drained. but plz explain how to do the inline check u speak of.
 
Checked pressure throughout entire line:
Again, after initial pressurizing by keying on I clamping after throttle fuel rail pressure holds over 40lbs.

Clamped after FMU/rising rate regulator (I also clamped the vaccuum line that goes from the TBs to FMU to take out of the equation). Pressure drops to around 30lbs and then holds.

With no clamp the pressure drops to 5lbs fairly quickly.



Is the FMU supposed to work like a one-way valve?

pressure.jpg





The pic below is where the stock pump used to be. This is what holds the stock pump in the tank. You can see where the fuel lines come in and out. With the turbo install you remove the pump and regulator from the tank. It's gutted. The fuel return line goes straight from the FMU to the tank with no check valve.

turb03.jpg
 
I was able to get the FMU to hold pressure by tapping on the side it but when I tried to dial in the pressure it went back to losing pressure again. As people have been saying, the pressure was an issue. I didn't want to believe it as the entire fuel system only has two seasons on it.

I'll probably send out for a rebuild kit.

The part that puzzled me was the intermittent starting. I think now that the quick starts were a result of enough pressure still in the line. During the longer starts the pressure would get so low that the pump would turn on so that part seemed electrical.

I'm going away next week so no more working on this until I get back. I'll work on getting the pressure issue solved and hopefully issues with starting will be solved. I'll post again if/when I have this fixed. Thanks to everyone here, I appreciate all of your help.
 
Post back if you find something, I'm curious.

Someone on another board said the pressure looked correct (for a turbo)

He pointed me back to sensors. The ckp seemed to make the most sense so I checked the resistance across ckp at the ecm. The ohms were incorrect so I tried again after removing PCII. At that time I noticed that I never disconnected the PCII entirely, I had left the crank sensor wires connected.

Anyway, I disconnected the PCII out entirely and the ohms were correct at the ecm.

I figured I would try hitting the starter button again with PCII out of the equation. Now, pressure builds pressure instantly EVERY time the starter button is pressed. Apparently the fuel system runs it's initial 3 second prime when keyed but will turn on again when it sees a signal from the ecm (while cranking) and remains on once started. I don't know why it read it while running but not while cranking but I guess it was the PCII.

For whatever reason with the PCII hooked up the ecm was only reading the signal from the randomly from the ckp. This is probably why I was having a hard time starting even prior to turbo install (the PCII was there when I bought the bike). I couldn't figure it out because it was only happening randomly.

So, HOPEFULLY this was it. Since the PCII is outdated anyway I'm going to buy a new fuel management system. HOPEFULLY this fixes it. :satisfied:
 
very very probable. when you removed the pcII started fine. i know i have read other posts here where the pc has played an issue.

good job.
 
very very probable. when you removed the pcII started fine. i know i have read other posts here where the pc has played an issue.

good job.


I just retried to make sure.
Builds pressure instantly without PC2.
No immediate pressure when PC2 is hooked up.
HOPEFULLY, that's it..............I'll see what others say.
 
had something similar on my 01 gsxr750 no pressure while pc was pluged in pressure when it was unpluged long story short there was corrosion in the conector cleaned it all up... a dab of dielectric grease and all was good to go
 
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