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Discussion Starter #21
Geoff, there are no open ends on my vacuum lines. They look exactly the same way they always have. Cylinders 1, 2, 3, and 4 are connected, and run to the MAP sensor. There are two separate vacuum lines that run out of cylinders 2 and 3, they are connected on a T and run to the FPR. My last FPR was leaking into the vacuum lines. The one I have in there now is only a few weeks old. I have not removed any of the lines, and I checked them all again. There are no cracks or tears. There are no open ends. Maybe the FPR is the issue, but it's probably not the vacuum lines. Am I able to upload pictures to this site?
 

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Geoff, there are no open ends on my vacuum lines. They look exactly the same way they always have. Cylinders 1, 2, 3, and 4 are connected, and run to the MAP sensor. There are two separate vacuum lines that run out of cylinders 2 and 3, they are connected on a T and run to the FPR. My last FPR was leaking into the vacuum lines. The one I have in there now is only a few weeks old. I have not removed any of the lines, and I checked them all again. There are no cracks or tears. There are no open ends. Maybe the FPR is the issue, but it's probably not the vacuum lines. Am I able to upload pictures to this site?
there are several ways to check injectors, the fuel rail can also be checked for pressure by connecting an air pressure gauge but you will need to buy one, I did this myself years ago, the manual shows how, you can also pull an injector out and look while turning the engine over - just be careful where it is spraying - into a glass jar works, injectors are off on activated like a solenoid the ecu varies the time they remain open therefor adjusting how much fuel is injected based on various sensors, the most important factor is the rail pressure which should be constant at 40-50psi - starting the engine and idle requires very little to run so the must something major/obvious going on to prevent this, fundamentally fuel pressure and fuel flow must be reaching a certain level for it to start. Injectors must then be pulsing open to inject the fuel and the spark plugs must be firing to ignite the fuel - I know this sounds simple and it is lol - fuel pressure is key

I think I asked you this already - is the inside of the tank rusty - it can happen if the bike has been sitting for a while with old fuel in there especially ethanol which eventually converts to water - rust will block the fuel filter very quickly - I had this problem years ago and had to stop and clean the fuel filter every 15kms - only fix was new tank

PS - if I remember correctly the motor will not run with the MAP Sensor disconnected

is the FI light still staying on with no codes showing ?
 

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Discussion Starter #23
Whats the easiest way to perform a flow test? I looked at five stores the other day for something I can use to flow the fuel into and measure it, but I couldn't find anything. I plan on renting a fuel pressure test kit again today, and I'll post the results here.

The inside of my tank is definitely a bit rusty, and possibly rusty enough to block the fuel filter. I can check that too. Again, would a blocked fuel filter happen over night?

I have to wait until my girlfriend gets home with my car in order to go pick up the fuel pressure test kit, but I should be able to get it done today and post what I found. Probably before 9PM PDT.

FI light is off now, and no codes are showing.

My best guess now is blocked lines/filter. I'll try to pull that filter out tonight.
 

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Graduated beaker or cup and a stop watch.
 

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Whats the easiest way to perform a flow test? I looked at five stores the other day for something I can use to flow the fuel into and measure it, but I couldn't find anything. I plan on renting a fuel pressure test kit again today, and I'll post the results here.

The inside of my tank is definitely a bit rusty, and possibly rusty enough to block the fuel filter. I can check that too. Again, would a blocked fuel filter happen over night?



I have to wait until my girlfriend gets home with my car in order to go pick up the fuel pressure test kit, but I should be able to get it done today and post what I found. Probably before 9PM PDT.

FI light is off now, and no codes are showing.

My best guess now is blocked lines/filter. I'll try to pull that filter out tonight.
forget about flow test, fuel pressure is No1, you need 40psi+ on the rail for the engine to start

setting that aside - if you have a rusty tank it is good for about 20mins running and then the filter will be so badly blocked no fuel will flow in any meaningful way, I already told you how to clear the filter with water in reverse direction and blow it out with air after, this will get you running for another 20mins - DO NOT REMOVE/BYPASS THE FILTER - it is doing its job even if it is blocked - if you try to bypass it then you are into replacing all your injectors


Rusty tank - I believe I suggested last week, you need a new tank
 

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Whats the easiest way to perform a flow test? I looked at five stores the other day for something I can use to flow the fuel into and measure it, but I couldn't find anything. I plan on renting a fuel pressure test kit again today, and I'll post the results here.

The inside of my tank is definitely a bit rusty, and possibly rusty enough to block the fuel filter. I can check that too. Again, would a blocked fuel filter happen over night?

I have to wait until my girlfriend gets home with my car in order to go pick up the fuel pressure test kit, but I should be able to get it done today and post what I found. Probably before 9PM PDT.

FI light is off now, and no codes are showing.

My best guess now is blocked lines/filter. I'll try to pull that filter out tonight.

on a ride out with a rusty tank I was stopping every 20mins and clearing out the filter at a gas station - yes removing the tank, pulling out the pump assembly and clearing it, I did this because I had tried some treatment to the inside of the tank but is obviously did not work- only solution - replace with a good tank

I did 100km that day and now I could remove the tank and filter blindfolded I did it so many times, the motor just starts hesitating on throttle and eventually dies and will not start - clear the filter and it starts right up


flow test - what's that lol
 

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volume is also key you can have 90 psi rail pressure but if your only flowing a gallon a minute and you need a gallon and a half it may idle and run fine up to a certain rpm then fall off but still have rail pressure. I have seen this effect on more than one hi performance engine build.
 
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Discussion Starter #29
Alright. Got the fuel pressure test kit. According to the service manual, I'm supposed to undo the line coming out of the fuel pump and plug the gauge in there, correct? If I were to just undo that line, would a bunch of fuel just start pouring out?
 

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volume is also key you can have 90 psi rail pressure but if your only flowing a gallon a minute and you need a gallon and a half it may idle and run fine up to a certain rpm then fall off but still have rail pressure. I have seen this effect on more than one hi performance engine build.
agree and I said pretty much the same earlier but at this point getting it started is the objective, keeping it running comes later :)
 

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Alright. Got the fuel pressure test kit. According to the service manual, I'm supposed to undo the line coming out of the fuel pump and plug the gauge in there, correct? If I were to just undo that line, would a bunch of fuel just start pouring out?
Yes
You'll have to drain the tank. You can use the FPR return line. It'll get most of it out. Then hook up the gauge refill the tank do your test and then drain it again.
 

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Alright. Got the fuel pressure test kit. According to the service manual, I'm supposed to undo the line coming out of the fuel pump and plug the gauge in there, correct? If I were to just undo that line, would a bunch of fuel just start pouring out?
no fuel will pour out - only from the return line that goes to the FPR if you remove that one which I plug with a tank bolt if removing the tank

clean the filter first like I suggested in reverse direction and see if it starts - if I am right you will see a lot of muck come out for a few seconds then blow it out with air to remove any residual water
 

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Discussion Starter #33
So, problem solved. Bike is up and running.

Geoff, the second I undid that bolt, all hell broke loose. Definitely had to drain the tank. Anyways, while the tank was drained I decided to have a look at my fuel filter. Come to find out, the line from the fuel pump to the fuel filter was disconnected. I feel a little dull. Thank you guys so much for all of your help, it was greatly appreciated.
 

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Discussion Starter #34
Oh, and now that there's actually fuel in the bike again, the FI light came back. Steady glowing. No codes.
 

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So, problem solved. Bike is up and running.

Geoff, the second I undid that bolt, all hell broke loose. Definitely had to drain the tank. Anyways, while the tank was drained I decided to have a look at my fuel filter. Come to find out, the line from the fuel pump to the fuel filter was disconnected. I feel a little dull. Thank you guys so much for all of your help, it was greatly appreciated.
fuel will run out if it is disconnected from the pump, I have my tank off many times and never have fuel running out of the pump output line, glad you found the problem

FI Light - try resetting the ecu, instructions are in the manual, in saying that it sounds to me like the "loom fix" may not have been done correctly, a constant FI light with no code is usually fatal and engine won't run
 
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