Injector not getting power.

[Pavel_proo]

So, I have been having issues with my fuel injected xciting 250. It doesn't start. However I was able to pin point the problem area. The fuel injector doesn't open up or sometimes does but not nearly enough to actually get the spray going while cranking however sprays perfectly fine and strong if I hot wire the injector directly to the battery. All that leads me to a conclusion that a connection is bad somewhere or the wires got rubbed and short to the frame somewhere.
No check engine light as well. Spark is fine. Fuel pump runs.

[CROSSBOLT]

I will bet yours is wired similar to the DT300i and you have a faulty relay!

[Pavel_proo]

I will bet yours is wired similar to the DT300i and you have a faulty relay!

I ordered a replacement relay but I believe that if the relay was bad the pump would not run either.

[Pavel_proo]

So, today I saw a check engine code 33-injector resistance not within spec. Maybe I didn't see it before, I am not sure.
However I checked the resistance of the injector and it is within spec at 11.5ohm.
I tried switching the fuel pump relay with a headlight relay and nothing changed.

[CROSSBOLT]

I ordered a replacement relay but I believe that if the relay was bad the pump would not run either.

You are right! Pump and injector teed off the same relay. Guaranteed that relay will not go to waste! Well, then bad connection definitely possible. Silicone dielectric grease/contact cleaner in all the connectors should either fix or rule out that.

[Pavel_proo]

After further investigation I found that the injector resistance measured between ground or pump relay connection and the contact at ECM is correct at ~11.7. However once I turn the ignition on the resistance measured at 0.7(between frame and ecm connector), so quite lower than 11.7 it should be. I think that should mean something but not exactly sure what.

[CROSSBOLT]

After further investigation I found that the injector resistance measured between ground or pump relay connection and the contact at ECM is correct at ~11.7. However once I turn the ignition on the resistance measured at 0.7(between frame and ecm connector), so quite lower than 11.7 it should be. I think that should mean something but not exactly sure what.

Sounds like you were measuring resistance with power on when you got that .7 ohms. The resistance check is done while injector is  disconected.

[Pavel_proo]

Spent half a day looking for messed up wires, but nothing.
Checked ecu for continuity as the manual says, all good.
Bike still shows code 33, even though injector resistance is correct.
Tried clearing the code with twisting throttle method, it wouldn't clear.
But I noticed that injector does spray now if cranking. Bike actually starts for like a few seconds and then dies.
Tried switching fuel pump relay, still doesn't work. I think I will try getting contact cleaner as suggested, but my contacts that I was able to check all look good with absolutely no signs of corrosion.

[CROSSBOLT]

Spent half a day looking for messed up wires, but nothing.
Checked ecu for continuity as the manual says, all good.
Bike still shows code 33, even though injector resistance is correct.
Tried clearing the code with twisting throttle method, it wouldn't clear.
But I noticed that injector does spray now if cranking. Bike actually starts for like a few seconds and then dies.
Tried switching fuel pump relay, still doesn't work. I think I will try getting contact cleaner as suggested, but my contacts that I was able to check all look good with absolutely no signs of corrosion.

I feel you are getting close! Don't quit! All the ECU "sees" is voltage so any thing in the chain can be the cause from the fuse, key switch, connectors, yada, yada. But only in that string that involves that injector.

By the way, try pulling that 30 amp fuse for 30 seconds to 30 minutes or anywhere in between to erase trouble codes. When you find the minimum time it will be quicker that throttle twist!

[Pavel_proo]

Got a new injector thinking mine might have been faulty. Nothing yet. Seems to squirt fuel just not enough. I originally thought that my fuel pump was bad and not pumping enough pressure. So I ordered a new one. In the meantime I installed an aftermarket one but that too didn't help. Should get a hold of a fuel pressure test kit tomorrow and check the fuel pressure first.

[Kansas kymco]

Got a new injector thinking mine might have been faulty. Nothing yet. Seems to squirt fuel just not enough. I originally thought that my fuel pump was bad and not pumping enough pressure. So I ordered a new one. In the meantime I installed an aftermarket one but that too didn't help. Should get a hold of a fuel pressure test kit tomorrow and check the fuel pressure first.

I have a 2009  Kymco 250RI I bought not running.  My fuel pump would pump gas but not enough pressure to start engine. I ordered a fuel pump assembly from Kymco on advice from dealer. My dealer explained that silver disc in the assembly is the pressure regulator and sometimes fails. I got the new pump installed hit the start button and fired right up.  I have a Yamaha Majesty as well that I replaced the fuel pump assembly on as well.

Both of these scooters are low milage Xicting  2k Yamaha 1300.  and  both sat for several years.

[Pavel_proo]

I have a 2009  Kymco 250RI I bought not running.  My fuel pump would pump gas but not enough pressure to start engine. I ordered a fuel pump assembly from Kymco on advice from dealer. My dealer explained that silver disc in the assembly is the pressure regulator and sometimes fails. I got the new pump installed hit the start button and fired right up.  I have a Yamaha Majesty as well that I replaced the fuel pump assembly on as well.

Both of these scooters are low milage Xicting  2k Yamaha 1300.  and  both sat for several years.

So I got a fuel pressure test kit and indeed the pump was only putting out like 5psi of pressure. Ordered an OEM but it is on back order till end of May. Figured I would try something else in the meantime and got a quantum hfp fuel pump replacement. Should be here on Wednesday. Let's see if that works.
However I believe the silver disk you are talking about is not part of the electric pump itself, but rather located at the top of the assembly and is not serviceable.

[CROSSBOLT]

So I got a fuel pressure test kit and indeed the pump was only putting out like 5psi of pressure. Ordered an OEM but it is on back order till end of May. Figured I would try something else in the meantime and got a quantum hfp fuel pump replacement. Should be here on Wednesday. Let's see if that works.
However I believe the silver disk you are talking about is not part of the electric pump itself, but rather located at the top of the assembly and is not serviceable.

Didn't anyone mention the Yamaha pump that seems to fit all the Kymco EFI fuel units?
Good you tested that with the pressure gage! 5 psi definitely won't cutnit!

[Kansas kymco]

So I got a fuel pressure test kit and indeed the pump was only putting out like 5psi of pressure. Ordered an OEM but it is on back order till end of May. Figured I would try something else in the meantime and got a quantum hfp fuel pump replacement. Should be here on Wednesday. Let's see if that works.
However I believe the silver disk you are talking about is not part of the electric pump itself, but rather located at the top of the assembly and is not serviceable.

That's exactly why you need the original fuel pump assembly,  like I said that silver disk is the regulator and can fail. Just replacing the pump you will probably still have low pressure. 

[Pavel_proo]

That's exactly why you need the original fuel pump assembly,  like I said that silver disk is the regulator and can fail. Just replacing the pump you will probably still have low pressure.

Yeah, I figured that. Anyway, I took mine out and found it corroded and seals rock solid and cracked.
And then I found an aftermarket pressure regulator available, looks the same as the oem.
https://www.amazon.com/dp/B08P3V54ZF/ref=cm_sw_r_cp_apa_fabc_SS4VXS0C1VKFNDWZBK2N
So I think that should work just fine. Fingers crossed. Will update later on once installed.