Honda CBR 600RR Forum banner

2007 Idle Issues

17K views 31 replies 7 participants last post by  AJ26 
#1 ·
Alright guys, I have a 2007 CBR 600RR. I have had issues with the idle for the past month. Here's the deal: RPMs would go up and down when riding around with clutch disengaged (bouncing off the 1, 000 RPM mark=almost like it is stalling/in limp mode). Then after a few days of riding, the bike idles higher at normal engine temp and will idle even higher with a rev of the throttle (~2,000 rpm). There is decreased engine breaking when using gears to slow down and bike jumps a little when shifting gears (like throttle is being held down=obviously the high idle issue).

After all this, I replaced the IACV (air intake control valve) to no avail. Decided to say screw it and took it to the Honda dealership. They hooked her up and said the air intake temp sensor (IAT) was throwing a code. They reset the ECU and said it was good to go. The tech said further that if it does the same thing again, I should replace the IAT sensor since it has gone bad.

My question is this, my bike never threw a FI light blinking code or anything of that matter. So, how can resetting the ECU temporarily fix a faulty IAT sensor (if that's the case)? The part is $15.00, so I am not too concerned about it. And it is easy to replace. I just wanted to see if anyone had this happen, has an answer for me, and to let everyone know that this issue is NOT always related to the IACV.

Thanks in advanced guys!
 
See less See more
#2 · (Edited)
Hey man, sorry I can't help (have mentioned and commented on the same issue before), but didn't get any solid advice on it. There are a few threads that mention the SAME EXACT issue, so you might find some answers digging around. The last guy I advised said he'd get back to me if he ever figured out what it was, but he never got back to me. That member and I concluded that the symptoms seemed to have started after we installed aftermarket slip-ons. The mechanics I've gone to have told me that it's probably because I don't have a PowerCommander. He had a Power Commander, yet still had the problem.

Years ago, the same symptoms occurred with my bike and another member gave me his advice. He went to the dealer and was told many different things and replaced many different things. He eventually found that his problem was some wires that were pinched on the left side of the tank. Upon removing his tank, he saw that the wires were smashed. Upon replacing them, the problem went away.

I never went as far as he did to "fix" my problem because it's random - sometimes I get it, sometimes I don't get. For the last few months, I haven't had the high idle at all, but I have gotten the low idling a few times.

This "problem" started for me about 2 years ago and since then I've put on another 20K miles on my bike.
 
#4 ·
sounds like a vacuum leak ... any work done on it before this started?

and if the tech said IAT, and its a fairly cheap part, that could also save you a bunch of heart ache..
 
  • Like
Reactions: Avodka14
#5 ·
I have heard vacuum leak before. Yet, their computer stated that my ECU threw a IAT sensor code and told me to replace it if the symptoms came back (they did). They reset my ECU and it ran fine for a couple of weeks and then went through the exact same process of bogging at idle while riding to a transition of high idle after a while. I would believe that a vac leak would not be alleviated by a ECU reset temporarily (figured, since it is mechanical, it would always be there.) Anyways, I really just wanted to see if anyone else has had an issue with their IAT sensor failing on them. If their computer says the IAT sensor is throwing a code, I would hope that is the source of my problem.
 
#7 ·
check it.... when your ecu's trouble codes were cleared it forgot what the iat was doing, once the computer realized once again the the iat was not doing what its supposed to it tripped the trouble code in the ecu again. it takes a few cycles of the sensor not doing what it supposed to, to trip the ecu. if that was the only code it put out, then probably its whats wrong
 
#8 ·
Ahh, thank you fiveostang! That is what I was hoping to hear as I was thinking the same thing and was told the same by the Honda dealership. This forum freakin rocks with people knowing what they are doing/talking about! I will keep you guys posted once the new IAT sensor is installed. Thanks again, everyone!:banger:
 
#10 ·
If the issue is intermittent, it won't set a code. It has to be in there for long enough to make it into memory for the FI light to set... transient faults wont do it.

The IAT could definitely cause idle issues though... other causes could be a gummed up intake, especially if you run ethanol fuels, problems with the PAIR system, vacuum leaks, dying MAP sensor etc etc... IAT seems like a good place to start in this case.
 
#11 ·
Alright guys,

I have replaced the IAT with no change. I suspect I need to reset the ECU because it has a fault code stored in it putting it in limp mode. It has to be that damn sensor since that is what the diagnostic tool coded for. Does the dealership have to reset the ECU on an 07-8 or can I do it at home? From what I have read, it has to be done with a special tool.
 
#12 ·
i think another way to reset the ecu is to remove the battery, i've read about it somewhere for cars, im assuming that it works on bikes as well.

search up before you do though, could be as simple as just disconnecting the positive terminal off the battery and letting it sit for 10 minutes.
 
#13 ·
Don't worry about 'resetting' the ecu. It will do that all by itself when the fault condition is no longer present...
 
#23 ·
:banghead:




Check the wiring from the IAT to the ECU with a multimeter.
 
#15 ·
I just jumped the DTC and the FI and HESD light stay on without blinking. I know there is no way for me to reset the ECM and clear the codes for the bike. The Honda dealer has to do that. It's an interesting situation because the bike does not have any blinking MIL. The dealer hooked it up to the HDS the first time I had over there and they said the IAT sensor threw a code. I have spoke to various Honda dealers and it sounds like a failing sensor can still work a little bit yet will store a code in the ECM without showing complete malfunction or a MIL.
 
#16 ·
Thank you everyone for your input and feedback. I am not sure exactly what happened but the bike is running fine now. I started it after jumping the DTC mulitple times today trying different combinations of wires. Anyways, I started the bike and just let it idle for about 5 min. It seems to back in action as far as I know now. For future reference to anyone who finds this situation interesting. I never had a MIL with this entire experience. Yet the dealership found an error code in the ECM for a faulty IAT sensor. Go figure. Guess the ECM is slowly adjusting now, that is my guess.
 
#17 ·
So it's confirmed, it was your IAT? I hope it remedies your issue for good. I haven't had the high idles in a long time, but I have seen the low idles lately.
 
#18 ·
James, it seems to have been my IAT sensor. I hope it is a long-term solution as well. I know when I had low idles riding around it was like the bike was working hard just to keep running. Then I believe the ECM re-adjusted everything and set it to a default higher idle. If the IAT sensor begins to fail, the info is sent to the ECM. The ECM re-adjusts to a default lower temp and thus the bike sounds like it is always warming up. Especially when you rev it, it will not go back down to a normal idle. Mine was also getting warm just idling for a few minutes. This is all from what I have been told and read in the service manual. Correct me if I am wrong.
 
#19 ·
Okay guys, she is idling high again. I can jump the DTC and it will go back to normal and then I will start it up again and it will back to high idle. I am not sure what the deal is with it. It rode well for about 2 days. Then it started it all over again. I really think I need to take to the dealership and have them reset the ECM with the HDS. Any ideas?
 
#20 ·
One more thing guys! I just jumped the DTC again and it idles fine. The first time it malfunctioned today, I noticed the MIL light blinked 9 times=IAT sensor. I can not get it to that again nor can actually clear the DTC. The only thing that happens when I jump it is the FI and HESD light stay on then go away after turn the ignition off. The bike also heats up to 225 deg and the fan kicks on to cool it down. What the hell is going on here?
 
#25 ·
No worries mate, I'll still be here if you need some help....
 
#26 ·
Sorry to bring up and old thread.

I'm having the same problem as well on a 09
I have installed PCV, Autotune, IRC, QS, QS module, Pairs removed, o2 sensor blocked off & servo eliminated.

Happened first time when the bike was hot about 77degrees would sit at 2,000rpm and not drop back down.
Followed troubleshooting found DTC Exhaust Servo, Cleared and no DTC.
Cleaned & checked throttle bodies, no leaks.
Tested ign on and off IACV & removed it to check found slight gunk underneath.
Cleaned and roadtest confirmed problem went away.

Re-roadtested 3 days later and high idle is back.
Does anyone have the fix for the problem on this thread or have the resistance check for the IAT and how to test the ECT sensor
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top