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Discussion Starter · #1 ·
My CX500T will not idle properly. When I start it, I have to hold the thottle open to keep it running and it seems like it is either starved for fuel or is not getting proper ignition. I pulled the plugs and checked the gap and they were fine. I cleaned them the best I could do with a rag. A little history is that I just got back from overseas deployment. I put fuel stabilizer in it before I left. I charged the battery and fired it up. It ran just fine. No problems for over an hour. I go back out the next day and now it barely wants to run. Any ideas?
 

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How long were you deployed?

Fuel Stabilizers don't necessarily work as long as people think.

I've heard of cases where the fuel turned gelatinous in about a year.



Also, one of your fuel filters could be clogged, your injectors could be clogged.
 

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Discussion Starter · #3 ·
How long were you deployed?

Fuel Stabilizers don't necessarily work as long as people think.

I've heard of cases where the fuel turned gelatinous in about a year.



Also, one of your fuel filters could be clogged, your injectors could be clogged.




I was gone a few days shy of a year. Where are the fuel filters located on this bike. I figure I can follow the fuel line back to find them.
 

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you have two fitted filter styles on the turbo



1. - fuel filter - in the tank - this could be clogged or deteriorated.

2. - fuel strainer - down stream of the tank - big metal thing

3. - you could also have another filter inbetweeen these two.
 

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First and foremost; I assume your a military member, so THANK YOU FOR YOUR SERVICE, SIR.

Now, on to your problem. It is process of elimination when dealing with a poor running engine.

First, fully charge the battery for good cranking and testing.

Then drain the tank, clean with some diesel or solvent and then make sure fresh fuel can freely flow out of the petcock. Next, pull the plugs and make sure they are not fouled ( a properly running engine will leave a cocoa brown appearance on the firing tip). Then ground the plug to the engine or frame and crank her over; should have a nice fat bluish spark, indicating the coils and wires are good. Is the "FUEL SYSTEM" warning lamp on steady while the engine is running? If so, then the computer has already diagnosed the problem for you and indicated it with codes blinking on the side of the ECM (let me know what the lights are). if the FUEL SYSTEM light is not on, then you may still have a sensor out of range. It is very common for the PB sensor to be out of range, but not set a warning code. Do this next: pull off the right side cover, shut off the engine and disconnect the PB sensor (it says PB sensor on top of it). Then restart the engine. The fuel system light will come on, however, if the bike runs correctly, you have found the culprit. Do this one at a time to the sensors until it runs correctly, then you will know which sensor, if any, is bad. Then we may have to test the ENGINE SPEED SENSOR (very easy with a multi-meter).........let me know how this goes first, and if you get stuck, let us know. All the help you need is here in this forum...............
 

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There are four fuel filters for the fuel to pass through on its way from the tank to the cylinder.

The filter inside the tank - a nylon mesh tube - which is for stopping the BIG stuff.

Then there is the main metal-clad filter in under the seat on the RHS - its the real stopper of the fine stuff which may be in the fuel.

Just at the inlet to the fuel pump, there is a small conical nylon filter - pushed inside the hose which connects to the pump inlet spiggot - to trap gunk which comes from deteriorating rubber hoses.

Finally, there is a VERY small cup-shaped filter in the inlet port of each injector. It's one that you normally can't change, but, if you take your injectors to be cleaned, its replacement should be mandatory for every service centre, and you should insist on this being done. If they won't replace that filter, go see another injector cleaner company.
 

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Discussion Starter · #7 ·
No luck with cleaning the fuel system. I tested all but the engine speed sensor and everything checked out. Any testing procedures for testing the engine speed sensor would be a lot of help!
 

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Check out this dude's youtube vids. It's an original Honda training filmstrip.



Youtube Link
 

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I assume you static tested (IE: measured with Key on and Key off) and compared to the Honda specs? However, do NOT ever rely on these readings. Start the engine and let it warm a bit. Then shut if off. Now pull the connector for the Pb sensor and restart the engine. If it runs and throttles correctly (and the FUEL SYSTEM light is on) then you have found the culprit. Continue this process with all of the other sensors, but not the engine speed sensor, as the engine will not start without it. If only one coil of the engine speed sensor is bad, then it will not idle good, nor throttle up. It is easy to check on the bike. Remember this about sensor parameters: "Code does not mean part, and part does not mean code". Simply stated, it may pass the static measure test with a multimeter, but it could still be faulty. Many times I have found a sensor testing good, but was faulty. When you unplug a bad sensor, then the computer shifts to default mode and allows it to run a bitter better, and turns on the FUEL SYSTEM warning lamp. Try this and let me know. We will find the answer.....
 

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I 2nd checking the Pb sensor. My bike was driving me nuts, running crappy down below 3000 rpm last summer. Diconecting the sensor resulted in an significant improvment. As HomerRod said the processor will put in values and the light should come on.Its a simple test and can eliminate a lot of troubleshooting.Good luck with it.
 

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Discussion Starter · #11 ·
Has to the engine speed sensor. Unpluged all other sensors individually after it was warm (not easy with it missing so bad) and ran it with a sensor unplugged. I am going to rebuil the engine speed sensor and go from there.
 
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