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05 wont really idle after a valve adjustment

3K views 21 replies 4 participants last post by  Flyers28 
#1 ·
Bought a used 2005 R6 with ~26k miles. Ran like a champ but was due for a valve clearance check. Decided to change air filter and spark plugs while I was at it.

Some valve clearances were pretty tight and out of spec so I readjusted as required and got all valves in spec. I put bike together tonight and rolled her outside to fire her up.

Bike started up right away no issues. Idled fine for about 10 seconds before rpms slowly dropped and she began to stumble. I tried adjusting the idle screw to the right as she sat there but she eventually died. Kept turning more and started her back up. This time she took a rev to get started and wouldnt idle at all. Anything below ~3500rpm she dies. Turned idle screw some more and revved the bike. RPMS flew to ~6-7k and SLLOOOWLY fell to about 5k and stayed. Lowed idle little by little until it hit 3500 and died again.

Now to start she takes a few turns of the starter and I have to give her gas. Shes slow to rev up but once around 4k if I hold the throttle the response is as it should be but it wont stay on below 3500.

Again, bike ran great before the adjustment. I also ran diagnostic mode and tested the TPS through that but it looked okay. 16 at idle and 96 at WOT. Response is right on point.

ALSO, I did a leak down test before I finished putting everything together. All cylinders were right around 4-5%.

Any ideas?
 
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#3 · (Edited)
Yes I checked timing marks after getting cams in and after rotating engine a few times. Then rechecked clearances and all was good. Marks on cam gears were lined up perfectly to the head when cylinder number 1 was at TDC on the crank mark.

Yes I had the throttle bodies off

I went through all diagnostic tests. All coils are sparking, all fuel injectors are injecting, and air induction solenoid is working too.

Odd result from diagnostic test was #03: turn engine stop switch to on and crank the engine using the starter motor to generate a pressure difference. Typical results are 10-200 mmHg. My screen read 4-5
 
#4 ·
OK, looks like you have an intake leak...or the ECU thinks you do. That is why I asked if you took off the TBs. Make sure they are fully seated, and all the hoses are connected. Pay particular attention to the IAP sensor. Item #10 in the attached
 

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#6 ·
So...

I took off the air filter housing and took a good hard look at everything on my throttle bodies. Everything is hooked up and the TBs are seated onto the engine well. I read a note in my manual about if the engine was having issues idling and the TBs were synced (no idea if they are but she ran fine last week so I assume they are), and if valve clearances are good then I should inspect the AIS valve.

Well, manual says the valve should be closed with no power applied and open under 12 volts. My valve is open under no power. I can blow air right through the hose, through the valve, and into my reed valves on the valve cover.

I have seen guides on people removing this valve and plugging the valve cover holes. Will do a quick test to see if this helps anything. Think this is my problem?
 
#7 ·
So I did another diagnostic on the AIS valve while holding it. The valve is actuated and if I try to blow air through it during the test it seems to work. I can blow air through until it actuates and then it is blocked. However, off of power I can blow air through. The manual (a Haynes) states that with no power applied, the valve should be closed and no air should go through. Is this just a mis-print? Anyone have any idea?
 
#9 ·
The AIS system is downstream of the exhaust valves so it should not affect your issue. Download your real manual from Here: R6Messagenet.com

You need the 03 manual and the 05 supplement.

Also check coils. But I still think you have an intake leak. Spray carb cleaner around the base of the TBs with it running to see if it reacts
 
#11 ·
Well I put everything back together. I am 100% sure I got the TBs on and the intake assembly on well. Started bike and had the same problem.

I recorded another video here:

IDLE ISSUE TAKE 2

You can see the bike starts up right away and idles okay. I watched it for a little to see what would happen. RPMs were a little bouncy. Revved it and it seemed fine. Thought I was in the clear. Until I went to rev it again and it stumbled. Thought maybe she just doesn't like idling at 1500 rpm so I wanted to adjust idle to ~1800. As i turned the adjustment screw, nothing was changing. If anything the rpms got more unsteady. Then, after a rev, rpms hung way up which to me, means my idle adjustment was set way to high. So I slooowly backed it down just to have it die out. Then same issues as before, hard to start unless I give it gas and rpms will not stay below ~2-3k without wanting to dive to 0.

After recording this I started her back up and sprayed starter fluid around intake and TB boots and had no change in rpms. Still acting odd. Barely staying together at low rpm and the rpms tend to hang once they get a little higher. Any other ideas? Should I rip everything apart to get back at my camshafts? Could this be a timing issue?

I do have a timing light I could attempt to hook up but unsure how informative that might be
 
#12 ·
!!PROBLEM SOLVED!!

After trying everything under the sun and saying every curse word I could think of, I tore the bike apart again. I figured I must've ****ed up my timing. Well, lo and behold, issue was clear as day.

Here is crank at TDC mark:


And here is where my camshaft was:


Woops, def off a tooth

Got everything back aligned. Didn't bother taking off the throttle bodies this go around.



Got it all back together and rolled her outside to fire her up. Started right away and sounded much better than before. Sorry for the shitty video quality but here you go.

Start video. Idle was set a bit high. Was working the whole video to turn it down

Thanks for the help guys.
 
#14 ·
Looking to check the valves on an 05 I just bought, 16769ish miles. Do you have to remove the TBs to get to them or not really? My clymer manual says to remove them but I'm all about not removing things if you don't have to haha


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