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Discussion Starter #1
Please tell me it's not in the tank!!

I have a problem I could use some help with. '04 TC88, stage 1 with K&N air filter and V&H long shots. When riding and letting the bike decelerate with throttle closed, the bike will sputter and sometimes die when I try to give it gas. I smell raw gas when this is happening. The bike will start up after it dies, and sometimes just playing with the throttle will keep it running. It was running fine, albeit not much power, until this happened. The power thing may be just my perception because I have other bikes that are much more powerful. It acts like it is choking itself out even tho it's injected, but the raw fuel smell has me puzzled.

I replaced the K&N filter this morning because it appears that the guy who owned it before me didn't try to clean it the first 7 years of it's life.

I am thinking:

1. Fuel filter?
2. Clogged or dirty throttle body?
3. Something much more expensive than either of the above.

Any help would be appreciated.

Thanks.
 

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Listen inside the open gas cap when you turn the key on. You will hear the fuel pump pressurize (whine) and then shut off. It should then be dead silent. If you hear any hissing, splashing, dripping ortrickling noises you have a pinhole in the pressurized fuel line in the tank.
 

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Discussion Starter #3 (Edited)
Listen inside the open gas cap when you turn the key on. You will hear the fuel pump pressurize (whine) and then shut off. It should then be dead silent. If you hear any hissing, splashing, dripping ortrickling noises you have a pinhole in the pressurized fuel line in the tank.
Thanks. I'll check that this afternoon.

Edit: Checked it this morning. Dead quiet after the fuel pump pressurizes.
 

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You probably need the Harley computer diagnostic thing to figure this one out. When the throttle is rolled 'off' (decel) the injectors should go lean. If you smell raw gas, the question is why are they dumping fuel?
Maybe one or both are stuck open. There are also codes that should be displayed.
Please correct me if I'm wrong, but I THINK 04 used a MAP (manifold air pressure) sensor? It has a hose that goes from the intake manifold to the sensor. Make sure it has vacuum and isn't plugged.
 

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Discussion Starter #5 (Edited)
I think I found the problem. After checking to ensure that there was no pin hole in the fuel line, I decided to pull the air cleaner cover off and run it without the cover. The bike still did the same thing, as I expected, but I just wanted it off so I could see if there was any fuel spurting or leaking when it happened. There wasn't. What there was/is, and I didn't notice it until this afternoon, was a check engine light coming on for a few seconds after turning on the ignition. I checked the codes and it's showing a P0118, which is an Engine Temperature sensor code.

This makes sense. If it has become disconnected or is sending a high or low voltage (or resistance, whatever it measures) to the ECU, then the ECU thinks the engine is still cold even after it warms up and is sending more fuel than it needs to the throttle body and probably leaving the butterfly valve closed.

I read elsewhere on this forum that it's probably just a loose connection from the sensor, but it only costs $37 (can't be true, it's an HD part!) so I'll feel better just replacing it and making sure the contactors are cleaned and sealed with dielectric grease.

I'll replace it, clear the codes, and report back after I get it done.

Thanks for all the help!
 

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Disconnect, clean and put dielectric grease in connection holes, reconnect.

Try it, it's cheap.

Al
 

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Discussion Starter #7
Disconnect, clean and put dielectric grease in connection holes, reconnect.

Try it, it's cheap.

Al
Will do... I hope to get it done tonight because tomorrow is supposed to be (probably) the warmest day we see in Denver for the next several months.
 

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Discussion Starter #8
Update: It was a bad ET sensor. I took the connector apart, cleaned it, applied some dielectric, put it back together and as soon as the engine warmed up it set the same code started back with the same problem.

Replaced the sensor and all is well.

BTW: The service manual says you need to remove the fuel bung on the left side tank to get a socket on the sensor. A 3/8" swivel worked without doing all that.

Thanks for all the help.
 
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