Surging Idle...Please help!!!!!

[cobravenom39]

Ok, so I had this problem a few weeks ago, and I bought a carbtune to fix and still the problem persists.

Here are my mods.

Two brothers dual slip ons
K and N air Filter
Pair valve mod (block off plates)

I capped the throttle body pair valve hose and the one under the airbox.

What the bike does is it idles at 1100 after it's warmed up, then it just surges to 1800-1900 rpms right before the fan kicks on. After the fan kicks on, the idle goes back down, but then it sometimes surges back.


I have checked to make sure everythings tight and connected properly under the air box and the throttle bodies and the bike runs like a raped ape but there is some surging.



Of special note, the bike's idle is rough even after using the carb tune. I connected it just like the manual says and maneuvered the air box around so everything could stay connected to it, and IT STILL IDLES LIKE sh!t.

I don't get.

Any help appreciated.

And I did search. All I could find was someone who had a similar problem, but he never said how he fixed it.

 

[kennym4]

If you find the answer let me know !!! I think my bike has been doing the same thing for a while. I was told I needed my throttle bodies sync.'d, but when I took it to the dealer they told me "Busa's don't need that done" (which I know isn't true) ?? Then the guy at the dealer asked me what it was doing, and I told him it will rev up to like 2000 rpm, and back down to 1000 rpm, and back up again. He said "that's the computer trying to get the oil moving through the motor".

 

[AJAY]

If you find the answer let me know !!! I think my bike has been doing the same thing for a while. I was told I needed my throttle bodies sync.'d, but when I took it to the dealer they told me "Busa's don't need that done" (which I know isn't true) ?? Then the guy at the dealer asked me what it was doing, and I told him it will rev up to like 2000 rpm, and back down to 1000 rpm, and back up again. He said "that's the computer trying to get the oil moving through the motor".

Whoa! Find another dealer.

 

[GSXcite]

Sync and throttle position sensor adjustment should take care of it. You might also check for vacuum lines that may have been left off when you were working on it.

 

[ktw88q]

if you find the answer let me know !!! I think my bike has been doing the same thing for a while. I was told i needed my throttle bodies sync.'d, but when i took it to the dealer they told me "busa's don't need that done" (which i know isn't true) ?? Then the guy at the dealer asked me what it was doing, and i told him it will rev up to like 2000 rpm, and back down to 1000 rpm, and back up again. He said "that's the computer trying to get the oil moving through the motor".

wow!!!!!!!!!!!!

 

[AJAY]

Is the surging new, or did it start right after you did some work (like the block-off plates)?

I'm thinking an air leak somewhere. Pull the fairings and spray carb cleaner around the edges of the block off plates and the hose you plugged. Spray around vacuum hoses. If the idle settles down when you spray a particular spot, you've found your air leak. Be careful not to spray your paint.

Also, unplug and replug any electrical connectors going to your throttle bodies.

Finally, Power Commander?

 

[ajblbv]

does a visual inspectino of ur throttle body look off?

 

[Mr Bogus]

Sync and throttle position sensor adjustment should take care of it. You might also check for vacuum lines that may have been left off when you were working on it.

+1 and then you need to check the temp sensors if the issue persists..

 

[Acehole]

Why did you cap the hose under the air box? Did you do the small air box Mod? If not, sounds like the air box flapper is not opening cuz of lack of vacuum. Just wondering.???

 

[DREW]

Sync and throttle position sensor adjustment should take care of it. You might also check for vacuum lines that may have been left off when you were working on it.

Hal is on the right track here. TPS and sync..

 

[dadofthree]

If it started right after your mods, then I would check my handy work first

 

[suzuki4life]

If it started right after your mods, then I would check my handy work first

I would figure a vacuum leak as said before.

 

[celticBandit]

Sounds like a vacuum line or a vacuum nipple cap was left off.

 

[mike1180]

Sounds like a vacuum line or a vacuum nipple cap was left off.

2nd that.
I think you had some lines off in another post didn't you?
One of the rubber lines may be cracked, or pinched.
I would check that too.
Good Luck!

 

[Spudley]

Sync and throttle position sensor adjustment should take care of it. You might also check for vacuum lines that may have been left off when you were working on it.

Yep, first check the TPS adjustment (in search archive) with the diagnostic plug, if out, reset. THEN scour motor for intake leaks, old pair connection, front of #4 throttle, flapper valve, vacuum package behind airbox. THEN have your throttles synch'd or buy a mercury tuner and do them again....very precise. THEN reset IDLE at 1150-1200 rpm's. THEN have a nicer day !!!!

Or bring it to me and I'll be more than happy to walk you through it. Where's Schaumberg ????.......

 

[cobravenom39]

I searched and found some info on the tps. But what do I need? Do I need a code reader, or voltmeter? Charles busa had the same problem, but I couldn't find his resolution.

Please help.

Search function for the TPS isn't helping.

 

[Spudley]

First you locate the diagnostic plug wire next to the battery box, left side, under seat, along frame. It has a black rubber cover on it. Pull it up through the seat section and remove rubber cover. Take a paperclip and insert one end in each receptor. Ignition key should be OFF until paperclip is inserted. Turn ignition on and read clock display. It should have a -C00. Notice the position of the (-) mark ?. This tells you you're in the ballpark. If the (-) is anywhere but in the middle, you're out of whack.......At idle, this adjustment is specifically for telling the ECU that the throttle is closed, thus the idle mapping is in order.

Don't start the engine, just read the display. Then turn the ignition off and take the paperclip out.

If the (-) is anywhere but in the middle, you'll need to loosen the torx screw on the TPS, and move it. Be gentle, this sensor is VERY sensitive. You can turn the key to the ON position, with the paperclip in place, and then loosen the torx and adjust the TPS. The (-) will move as you do giving you feedback on the adjustment. It will also, sometimes, move slightly as you tighten the torx screw. If the (-) adjustment moves off the middle as you tighten, go back and do it again until the (-) stays put. Then double check by turning the ignition off, then on again for validation.

Once this has been checked, move on with the vacuum line checks, and idle adjustment. Once all your vacuum leaks have been solved, it'll adjust easy with a synch-tool, and idle should be between 1150 and 1200 rpms.......no more surge just low and steady.....

 

[GSXcite]

Good post Spudley

 

[cobravenom39]

Good post Spudley

Yeah, that's a solid explanation. One question. How many receptors are there. Do I need to check each one withe paper clip? Do I need to turn the engine off before removing and re-inserting. Are there two receptors and do I stick one end of the paper clip in each receptor at the same time? How hard to I jam it in.

I'll do that later tonight and let you know how it comes out.

Thanks again for the suggestions everyone!!!!!!!!!!!

 

[GSXcite]

The plug has just two connectors. The factory tool used for this is just a connector with two wires and a toggel switch. All you have to do is complete the circut. I use the paperclip too.