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Must keep fast idle fully open 2003 GSXR

172 Views 8 Replies 5 Participants Last post by  peter079
Good evening all,
Appreciate everyone's constructive advice.

I traded a 2003 VROD for a 2003 GSXR600 because... Well, I was not a fan of the VROD, just boring!

I rode the GSXR before we traded and it ran but it bogged down at times. The guy said the bike had been sitting for several years and that it was junk getting caught in the system. I brought it home, took the tank off and cleaned all the crap out of it. I also changed the fuel pump, the fuel screen, and all the gaskets. Could not change the fuel regulator because the kit had the wrong one. Also, a weird thing that someone could enlighten me about... there is a secondary wire from the fuel tank harness to the negative post of the battery. What up with that??

Next, I changed the injectors, plugs, and put a new battery in it. Started right back up but now I must keep the fast idle lever fully open for it stay running.
I tried to street-test it and it rides ok except that it stutters sometimes but then picks back up. AND it is a pig and WOT.

My question is, could it be the fuel regulator? In full honesty I might have used some brake cleaner sprayed directly into the fuel regulators (not thinking about it). Anyone think that that might have damaged the diagram in the regulator?

Open for questions and unrelented jokes about my stupidity...
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I just saw this. Usually the GSX-R regulars jump in sooner and have constructive answers.
You changed a lot of things already. Not sure why your idle is off now though.

Are there any check engine lights on? Perhaps you could search on how to put it in dealer mode and read the codes- if any. That is usually very helpful.- the codes, if any.
Putting it in dealer mode is simple and takes a small piece of wire, or a paper clip.

Good luck, some of the people that know things will chime in soon.
No codes "C00" Played with idle and got it to idle without the fast idle. Now I get a good pop and I can shoot a flame at least a foot from the exhaust!! Toooo rich!!
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We have had a few people forget to plug the vacuum hose back into the Intake Air Sensor
after reinstalling the airbox. Makes the bike run really rough and rich.
You might want to check that.
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The one on the right (upper) and the one in the middle neat the throttle bodies are both connected.

After adjusting the idle, I took it our for a short (2 miles) run. Ran soooooo much better. Came back and I lost the pop and the fire shooting out the exhaust.

Not sure anything is fixed but it's running.

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Get the injectors cleaned when u get a chance
Yeah, I meant the small vacuum hose on the left that plugs into the sensor.
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That was the magic fix! I did not know that hose existed. It was just laying on the motor. Now I wonder if I even needed to go through the fuel system. Ohh well!!

Thanks for the assist!!
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Ahh yeah, your not the first.
On the later models suzuki put the sensor on the throttle body so you don't need to unplug it
all the time.
Those hoses are pretty important and need to be in good condition otherwise the bike runs
like [email protected]#t. Even the one in the photo(not mine) looks like it has some cracking on the inside
and should be replaced.
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