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Discussion Starter #41
Agree with beestoys, fuel or starting fluid. Carb cleaner designed to clean, not fire.
So is the proper procedure for this to spray in one intake tube as you crank the starter, or spray in all four then crank?

Or just ”fire hose” across all four as someone else holds the starter button down?

Do you spray a lot, a little
 

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Discussion Starter #42 (Edited)
Well there is definitely no gas getting in the intake tubes.... Dry, never anything spraying in.....

I opened the gas cap and looked into see how much gas and decided to pour in some more. While I had it open and looking in there I turned on the ignition and when the pump primed fine bubbles came up through the gas....

Kind of emanating from where the fuel pump sock is located. I have a video but not sure if I can post videos here.....

Is it normal for bubbles to be coming up in the gas tank? Is that just the return gas from the FPR? Or is maybe the pump leaking down there on the outlet side.

Also I pulled the vacuum tube off the FPR and while cranking placed my thumb over the end and feel a very slight pulsing suck. Should the suction in that line be strong, or just barely noticeable? I am wondering if the FPR is working right.... It is brand new and a Honda part, but maybe I screwed up installing it, even though all there is to do is insert the sleeve and tighten down, but I have screwed up simpler things.

0D115452-795C-484C-8E13-FE8D58420993.jpeg
 

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I would do just a quick burst in each one in very quick succession and hit the start button. If it fires then you know it will run. Or another way is to get a 20 oz soda bottle and drill a "small" hole in the cap. Put some gas in the bottle then cap it. Squirt some gas in the intakes a little bit and see if it will run. Luck!

Sent from my SM-N960U using Tapatalk
 

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Fog em all and see if it'll fire
Then you only have one path to chase. (No fuel). If it does light off.
 

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Discussion Starter #45
Bought some starter fluid and it fired up. Did it twice and both times fired right up.

So what can prevent the injectors from spraying gas but not throw an ECM code?

FPR - brand new
- can anybody give me the Cliff Notes version of how this thing operates?
Fuel pump / filter / tubing in the tank - brand new
- the pump primes and gushes out gas at the tube end when disconnected from fuel rail
- there are bubbles in the tank when the pump is running / priming (is this normal?)
Vacuum lines all appear connected
- can a disconnected one stop the fuel flow

Any thoughts on what to check first?
 

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Odds of all injectors going bad together is very low. It is possible for a component or a wire to fail and the ECU not throw a code.

Double check all wires/ connectors and ground points and also the 2 large ECU connectors. Check very carefully for broken wires at the point they attach to these 2 large connectors.

Without special tools, you can check fuel pump for flow rate using a stopwatch and a beaker. I forget the details, they are in the service manual available on this forum.

Disconnect the battery before messing with the ECU. **
 

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Discussion Starter #47
Well, not sure if this removes the ECM / wiring harness, to the injectors, from the equation.

With the injector connector removed and then turning on the ignition I measured the voltage across all four connectors and got 11.90 VDC between the plug and ground.

Interestingly the fuel pump does not prime when an injector is disconnected.

I also tried the “sounding rod” on the injectors with a screw driver trick (don’t know why the pic is upside down). While cranking the starter and throttle.
5E0AC9F0-18E3-4C07-A09F-2AE82E1C27D9.jpeg
but couldn’t hear poop over the engine noises.

OrderEd a semi-cheap “mechanics stethoscope“ from Amazon so will try that on the injectors in a few days.

Does anybody have suggestions on verifying if the FPR is working right?
 

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Cliff notes are as follows
ECM is looking for crank and cam triggers to fire the injectors along with TPS signal.
First order of buiseness is to verify both of the pulse generators are sending a signal
They are hall effect sensors so you'll need a PVA Peak Voltage Adapter to check them. Once they are verified you'll need to chase them back to the ECM. Through the harness. There are instances where you can drop either of these signals and not trip a FI fault.

This would be my first check.
 

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Bought some starter fluid and it fired up. Did it twice and both times fired right up.

So what can prevent the injectors from spraying gas but not throw an ECM code?

FPR - brand new
- can anybody give me the Cliff Notes version of how this thing operates?
Fuel pump / filter / tubing in the tank - brand new
- the pump primes and gushes out gas at the tube end when disconnected from fuel rail
- there are bubbles in the tank when the pump is running / priming (is this normal?)
Vacuum lines all appear connected
- can a disconnected one stop the fuel flow

Any thoughts on what to check first?
Sorry to hear about your bird, and to ask the obvious.. I assume you checked all your fuses?
I think you’re looking at injectors, if your tank wreaked of Varnish/schlack then I’d expect the fuel sitting in your injectors gummed up also...
How many years did it sit?
In automotive when I benched tested/cleaned injectors, I had pretty good luck activating them with some jumper leads, you will feel them click.
Hth
 

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Give the cam sensor wires at connector a tug to make sure it is fully seated in. Disconnect and take a close look for any mean greenies. Low voltage on hall sensors can cause weird-ass sh!t.
 

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Discussion Starter #51
Update #3:

First off thanks for the additional thoughts and suggestions, they are appreciated. Here is some additional results for your consideration;

1) Got a Noid light and all 4 injector connectors blink the light, so they are getting signal to pulse.
2) Tested the fuel flow from pump, thru the rail and out the return line, service manual says 7.4 oz in 10 seconds and I did it twice and got about 10 oz in 10 seconds.
3) Put my old FPR back in to see if maybe the new one was not functioning correctly, no difference.

Been contemplating removing the fuel rail and injectors to clean then, but don’t think that is the next most likely. There has been no sign of “gunk” or “varnish” any where in the fuel path.

......... to be continued
 

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Discussion Starter #52
Now I am getting a headache......

I was looking through the service manual and noticed the “Engine Stop Relay” and wondering if that could be making my engine stop running. The service manual tells how to test it but really doesn’t clarify what it does.... I looked through the Wiring Diagram in the manual and it appears to allow 12VDC positive to all 4 injectors when the coil is engaged.

It failed the test, I applied 12VDC to the coil and there is no click and no continuity on the output..... So did I maybe stumble onto the issue for no good reason????

I don’t know why the Noid light would show activity on the injectors if there was no 12VDC positive coming through this relay??????

But anyhow I got another relay RC-2208 on order and will see what happens when I replace it.

But now here is the main reason for my headache, twice after testing this relay I plugged it back in and hit the starter button and got a very short fire of the engine. It sputtered... both times, like for one fraction of a second, but definitely it fired. Nothing after that, until I unplugged / fiddled with / repluged.

Well I will be happy if this is the problem and no point in saying what I will be if there is no difference after replacing the relay...
 

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Your fuel flow test shows the pump is probably OK. It does not indicate the condition (good or bad) of the FPR as this device needs engine vacuum to operate.

The ECU provides power and ground for the injectors. They wont fire unless it is getting all the proper signals such as crank position sensor etc.

Ok, the relay in question. Please test the relay before replacing it. Just need some wires, a multimeter (or 12V bulb) and a 12V power source. If the relay is OK, then you may have a bad/broken wire or connector or device in that circuit. From memory, that circuit includes the start/stop switch, ignition switch, sidestand & neutral switch, tip over switch. Note: possible to temporarily fool this circuit with a paperclip.

Did anyone mention the loom fix? There is a junction block in the loom that corrodes and causes electrical maladies.
 

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Discussion Starter #54 (Edited)
Headache Update:

The Engine Stop Relay is working, may have been the whole time... Or maybe fiddle dicking with it freed up the contacts... My homemade power lead was loose and playing with it more now the relay clicks. The resistance on the coil is 103 ohms, which another post here tells me is good. I get continuity when the coil is energized.

But now the engine starts... the split second fire mentioned above is now a constant “running of the engine” as long as I keep the throttle open. Close the throttle and it dies.

Can’t keep running with out throttle being open some, not a lot but none and it dies.

Sounds like I am at a different problem now, any ideas what is next?

Fizzy, yeah I have read and watched several videos about the loom fix... Sounds and looks unpleasant from what I have seen. In general the wiring of the bike is in very good shape, I haven’t seen any ”corrosion“ on any connectors, no frayed or damaged wires, no chicken poop wiring modifications..... Hoping to avoid the ”loom fix” for now.
 

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Actually sounds like your idel setting is so low. There is a black knob on the stator side of the engine. clockwise increases idle counter decreases. give it a couple turns clockwise the cover the kill switch. in case thats to many turns.
 

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Discussion Starter #56
Actually sounds like your idel setting is so low. There is a black knob on the stator side of the engine. clockwise increases idle counter decreases. give it a couple turns clockwise the cover the kill switch. in case thats to many turns.
Beestoys, yeah I have been reading up on the throttle stop screw and was tempted to mess with it.... I have not made any adjustments to this screw since last time it ran (5 yrs ago) and ran normal. But it is certainly possible it can be the fix, are there any downside to adjusting it? The manual says to adjust after “warming the engine for 10 minutes”.
 

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No
Just as i said cover the kill switch in case it takes off. Also i'd stay with it till it's fully warmed up. It may clear out and the idle may start to climb so just keep an eye on it for the first 10 minutes or it comes up to full warm up.
 

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Discussion Starter #59
Well I forced it to run for about 3 minutes by keeping the throttle open and running around 2500 rpm. After that I touched the exhaust pipes at the head and #’s 1, 3 and 4 were not at all hot, could easily touch them. Now #2 was hot, hot as it should be.

So my guess is I got three plugged injectors. Sound reasonable? Is it possible to run on one cylinder? It didn’t sound normal, rather rough and as before would just die if I let off on the throttle. I have Two Brothers slip ons that make it louder than stock exhaust, so much so that about 1 month after installing the slip ons I got the noise reducing baffles.

I saw a post here from “TheDuck” that details how to remove and clean the injectors....

I would recommend pulling the injectors - you don't need to remove the throttle bodies as the manual says, simply one screw for the MAP sensor and the two nuts on the fuel rail and you can lift the rail out of the way and then pull the injectors. You will find they stink to hell if new fuel hasn't got through to them (which it won't have if the injectors are not being activated). A soak in 'new' petrol is generally what they will need...

Doesn’t sound too bad, just curious of the survive ability rate of the o-rings and seals. Has anybody done this and did you have to get new o-rings and seals? Because from best I can tell those only come with the $168 new injector from Honda. Unless somebody has found alternatives?
 

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Or another way is to get a 20 oz soda bottle and drill a "small" hole in the cap. Put some gas in the bottle then cap it. Squirt some gas in the intakes a little bit and see if it will run. Luck!

Sent from my SM-N960U using Tapatalk
Do this into the dead cylinders while running to confirm if it is a fuelling problem. Otherwise, it may be a spark issue.
 
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