FUEL STARVATION!

[NICKSLICK]

I have an 02 HAYABUSA with an IN TANK FUEL pump.

anything over 9k, and my bike falls on its face from fuel starvation.

Here is what I know so far:

- ive installed a fuel pressure guage
- the fuel pressure guage shows 42psi steady from idle to 9k
- the bike falls on its face at 9-10k
- the fuel pressure guage shows 24 psi above 9k.
- i cleaned out a bunch of poop from the big filter in the FUEL PUMP designated number 3 on the diagram below.
- i ran the bike for a day, and then rechecked the filter again, and it was perfect.
- i replaced the stock fuel injection lines with steel braided lines and ensured no crimping.

- tried running the bike with no gas cap, to ensure no vaccum.

- changed the fuel pump with a new one, still getting low fuel pressure above 8k (20psi!)

- changed all four injectors

now im looking to go thru every filter in the fuel system! so far, i have located and cleaned the filter located at POINT 3 in this diagram.

CLICK HERE FOR DIAGRAM OF FUEL PUMP ASSEMBLY


WHAT IS ITEM 2 IN THE DIAGRAM?
isnt this the fuel regulator?
if not, where is it?
isnt there supposed to be a filter between the fuel regulator and the pump?

WHERE ELSE ARE FUEL RELATED FILTERS LOCATED ON MY BIKE???! there must be more than one, and its the clog i hope!

please help me if you know where any other filters that could be causing low fuel pressure may exist.



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[Cookie]

It appears that 'number 2' is a clip.

Hang on, i'm looking

 

[Cookie]

Have you replaced the vacuum damper or the vacuum control solenoid valve?



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Reason for Edit: "re-thinking"|1069907478 -->

 

[NICKSLICK]

Have you replaced the vacuum damper or the vacuum control solenoid valve?

where are they?
how can i test them to see if they are the cause?

what can i do, besides replacing, if anything, to repair it?

 

[Cookie]

The 'vacuum control solenoid valve' allows the vacuum line to open or close on the basis of electrical signal supplied from the ECM. The 'vacuum damper' is also provided in the line for the purpose of suppressing and stabilizing vacuum fluctuation.

 

[Cookie]

you have a service manual, nick? page 4-22

 

[Cookie]

or I could scan and email it to you?

 

[Cookie]

When the engine is running in a medium to high speed range, the signal from the ECM discontinues. Then, the solenoid coil is 'de-energized', causing the vacuum control solenoid valve to let atmospheric pressure into the diaphragm side vacuum line, which 'deactivates' the diaphragm and allows the spring to return and open the intake air control valve through the connecting rod.

I think you could, once located, check the valve with an ohm meter or manually seeing if the rod opens(?) and closes(?)

Since the diaphragm is mechanically connected w/ the intake air control valve via the connecting rod, the diaphragm pulls down the intake air control valve to close, thus giving proper operation.

 

[†WÃ￾§†ëD]

that very same thing happened to my 02, it ran real lean above 8k. I had the shop deal with it under warranty(extended), they said it had a clogged filter in the pump and a crimped fuel line? they said they fixed it, I havnt put it back up on the dyno to check it but it definetly runs better...

 

[STUNNAH]

My bike is doing the same thing...In 2nd gear at 9000rpm's it feels like it's dead then all of a sudden it's back up and running...I'll continue to watch this post...

 

[Cookie]

So what happened here?

First there's a fire,,,,then ?

 

[Rhythm]

kie
Seasoned Pilot



Group: Members
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Joined: May 2002
Location: ,,,let me think about that one! Posted: Nov. 28 2003,10:07

--------------------------------------------------------------------------------
So what happened here?

First there's a fire,,,,then ? [/QUOTE]



Everybody hauls ass for the exits

 

[STUNNAH]

I forgot I had the manual on CD...Been checking it out...

 

[NICKSLICK]

tomorrow, im going to switch tanks with a buddy of mine. this will tell me if there is anything in the tank side that has the problem, including pump, assembly, filters lines, etc.

ill let you know what i find.

 

[NICKSLICK]

tomorrow, im going to switch tanks with a buddy of mine. this will tell me if there is anything in the tank side that has the problem, including pump, assembly, filters lines, etc.

ill let you know what i find.

switched the entire fuel pump assembly with a known good one, PROBLEM SOLVED.

so here is what ive learned, something BESIDES the pum and the FILTER was the problem. i bet its the fuel regulator thingy majigger.

im gonna take the broken one apart shortly and see if i can figure it out.

 

[†WÃ￾§†ëD]

good go nick...