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03 r6 rough idle

16K views 26 replies 11 participants last post by  BlueBOB 
#1 ·
hi im new to this forum and also new with bikes. I bought my r6 last summer with about 6k miles and it was running great. However a month or so into the season it started having idle problems. The idle cut in and out and it got so low that sometimes the engine would just die. so i had to turn up the idle a bit to like 1800, but it would still sometimes cut in and out. And it didnt just end there, it also, maybe 3 or 4 times the whole season while riding would just die when i pulled in the clutch and when i let go rpms would go back, it would also back fire really bad when this happened. Also when it would idle bad i would turn off the bike and put the power comander in program mode and it would idle fine, and sometimes come back but sometimes not. Could it be a faulty power commander? or maybe the coils? i still have to check whether i got the bad densos or not. And one more thing while riding, keeping the rpms steady at like 5k, the rpms sometimes drop a bit then go back up causing a very tiny jerk.
well im determined to fix this problem before i start riding again so any suggestions will be much appreciated.
thanks
 
#2 ·
Sounds like coils to me. I did have a problem with a PowerCommander III, the bike would shut off sometimes when decelerating into a turn around 10K rpm. But DynoJet replaced the unit and I've had no problems since. From your description, it sounds like you have a PC V, correct? If so, that is probably not your issue, unless you have a bad connection in the PC wiring harness.
 
#4 ·
Your yamaha dealer should change them out for free. I had the same problem with my bike looked at the coils and had densos. There was also a recall on the front sprocket nut if i remember correctly. I had to pay for new plugs though, it was like $40. Hope this helps.
 
#5 ·
sounds more like a bad throttle position sensor the 03 and 04 was plagued with.
they are pretty expensive. over $100. and just because it tests good doesn't mean it isn't bad. my buddies tests just fine but we swapped it out with mine and his bike ran perfect.

his was randomly stalling.
 
#6 ·
mine seems to be the same at idle just kinda loading up but once you take it down the road it clears up. i just got the bike about 2 weeks ago weather has been kinda crappy so haven't had a chance to ride much. as far as mods it has a yoshi pipe and k&n filter as far as i know. new to bikes but work on cars a lot so shoot me some stuff to look far. can u take and clean the maf sensor on these bikes like u can on a car??? also thought maybe since the guy just has recharged the filter maybe he put to much oil on it???/ any help would be great
 
#8 · (Edited)
there isn't a MAF on a bike.
they have 4 separate throttle bodies. it could just simply need a good synchronization.
the synch of the throttle bodies plays a big part of the good smooth idle.
with an aftermarket pipe they will fluctuate slightly at idle.(100-300rpm typically)
that's normal.

look at the top of the coils. if they are a light tan epoxy top without any sticker that's the mitsubishi coils that are the good ones.
the bad ones have a black epoxy top with a black and white sticker that says DENSO on it.






 
#7 ·
check to see what coils youve got.... you can still get them covered but you need to call yamaha and get an approval code to bring to the dealer (i had to do this last summer)

also as everyone has said there is a known issue with the tps and there is a monitor in the self diagnostic section of the gauge cluster. the FSM will tell u how to find it.

im a master tech with a full shop at my house in keene nh (may not be too far from u) if you need any help just pm me and bring the bike up
 
#10 ·
well i just finished talking to the guy i got the bike from here at work and he said that the coils have been done about 5k miles ago. he had them done right after he got the bike. Also said the bike would do this in cold weather when he had it but once summer gets here it quits.
 
#11 ·
so i finally got a chance to check out my coils, lol i know its been a while. but i found out that i do have the old denso coils. i didnt get a chance to inspect them because i just took off the mid fairing and took a peak. but im gonna give yamaha a call tommorow hopefully they dot give me any bs.
 
#16 ·
Old topic I know but I was searching becasue now I had the same problem. This is just an insight on those who adjusted the TPS with no results, or don't have bad coils and still get these same issues. I solved mine but cleaning every wire connection under the seat the corresponds to the battery. I started by removing the grounds and positive terminals and wire brushing them. They were clean and didn't have corrosion but I did it anyways. There is a small box with two fuses next to the power cable that also has a white connector going into it with four wires, take that connector out and with a small file (what is used) or sandpaper clean all for of the spade terminals in the little black box and spray a contact cleaner in the white plug. I then moved to the negative side of the battery. Trace the negative cable back to the engine. You will need to lift your gas tank for this one, no biggie. There is a white single connector that ties to the negative terminal and connects to the main harness that runs along side the inside frame. Disconnect this and mine was corroded heavily. Clean this with file / or sandpaper really good!! This is what grounds your ECU (brain) of the bike. I think what happens is driving around it develops a bad ground and the ECU resets while driving but since the bike is in motion or in gear, it isn't quite dead until you pull the clutch in. I believe that this is why turning the key on and off temporarily fixes the problem... Now were was I, oh yea, cleaning the single connector, spray contact cleaner into the other side of the plug, there really isn't a easy way to clean this so this is what I did. Follow the larger black wire to the engine block and it should be attached by one bolt. With this bolt you can look on the top of it and see if there is any corrosion, if there isn't then dont remove, if there is remove it and clean it good. As a pre-cautionary measure I also ohmed the cable from tip to tip, if you ohm anything other than 0, there is corrosion in the cable and it should be replaced. Connect everything back up and also I pushed on all the connectors under the seat just to make sure they were all seated, even the ECU, then start! Its been running great ever since.

I'd like to add, I have a 2003 R6, I already did the TPS, cleaned old one, didn't work so bought new one. I did the valve adjustment, im at 24k. I have the carbtune and sync'd throttle bodies, it cleans up the idle, but it still died. Topped coolant, went through all the senors, cleaned air filter, changed oil, new spark plugs.

The above was the only thing that fixed this. I was never able to duplicate the problem in the driveway only when I drove. I stumbled across this becasue I had the bike running and the seat off and I started pulling and pushing on the harness and connectors, kinda hard, but not hard enough to break stuff, and instantly when I jiggled the main harness with the negative (white singe plug) my bike idled lumpy and died, Then I couldn't start the bike without the key on and off, so I cleaned everything. I was racking my head, hopefully this helps people who are at minds end like I was!!
 
#17 ·
A PC III might help.
 
#19 ·
Sorry for the old thread revival, but I'm rather concerned. Picked up an 03 R6 last April and have been slowly but surely modding it and enjoying it. I have a PCIII and just recently installed the AGG smog block off plates. Started fine immediately after install, rode it quite a bit yesterday, and even a little today. All of the sudden, while riding, the bike just all of the sudden started running like crap. No power and almost a gurgling exhaust sound running very rough. I confirmed my plates were still on tight. Thinking it might be the coils, but haven't looked closely yet. I also fear the plugs are probably the OEM plugs from when the bike was bought. The previous owner wasn't the type to turn wrenches and the bike only had 8k miles on it when I bought it. Any thoughts?
 
#21 ·
I did discover the issue. I confirmed with the only dealer that was open the next day (MLK Day) that the bike had never come in for the coil recall and sure enough all 4 of mine were the denso's. So, got that taken care of and she's all back to normal now. Also found out the plugs were only 2 years old which mean they probably only had 1 or 2 thousand miles on them. No wonder they looked so good!
 
#22 ·
My mechanic says my coils+spark plugs are ok, and that he is going to do a compression test tmo... I hope my problem is nothing too serious.

Do they still replace the coils free of charge ? Even though the biek is so old ?? Mines an 03... Are u from the USA by any chance ? I think the european models like i have came with the better coils, because of strict emmisions regulations... So we dont have the Denso's AFAIK
 
#23 ·
Yea, mine is an american bike. I think it was bought here in Dallas, TX. I just called the dealership and they confirmed my VIN was impacted by the coil issue and that the VIN I provided had not been brought in for the coil recall. The denso ones are obvious. They say denso on the very top of the coil.
 
#25 ·
not a problem.... still very odd that the problem didn't follow the coils if the headers are cold... compression would be the next step, or maybe the injectors? still very surprising that it's two cylinders in one shot all of the sudden
 
#26 · (Edited)
Yeah its causing me alot of stress and worry as i cannot quite figure it out.

It worked one day, and didnt the next.

Im thinking how could the compression suddenly go in two cylinders like that over night ?

My friend ruled out the possibillity of it being an electrical problem, thank god in a way cos i was thinking my ECU was dicked. The EU ECU's have built in immobilizers, they are hard to find, usually back-ordered and cost near or over €1000.

"The good news is ur ECU is fine, the bad news is, ur vales and/or cylinder could be ****ed !"

It just keeps getting better and better...

Im thinking i might just get 4 new spark plugs and a couple good second hand coils (If i cant get new ones for free of course). And see if it works, the risk being needlessy spending all that money and parts that dont fix it.

The worst part is the 2 hour bus journey to work every morning, with my bike its only 20mins ! Such a waste of time !

Sorry forgot to mention, i think the injectors are ok as i can smell some unburnt fuel coming from the exhaust... But they will need to be checked if the compression test passed.

i dont know whats better, bad injectors, bad compression or bad ECU(which we ruled out), i wish it was a simple spark plug issue !!!
 
#27 ·
Mine started running like crap mid ride, so I understand the fear. Since I had just installed the AGG smog plates, I feared one had popped off or something. I was thankfully lucky. Hopefully your issue doesn't become a massive one.
 
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