Rough Idle, Power issues, Fuel etc.

[RossKean]

I apologize in advance for a long post...

On Tuesday, on my way to the NERDS gathering in Vermont, I ran into rain in New Brunswick and it was pretty steady to beyond Bangor. I gassed up in Calais and headed across on the #9. A half hour outside Bangor, the bike started to run VERY roughly. I stopped in Bangor and almost didn't get it started again. Had to keep the throttle up and running was rough with poor power. After an hour or so (and less rain) it ran better at high RPM but still very rough below 2500 RPM. (Gas mileage sucked as one would expect from a poorly running engine.)

I camped in Gorham NH overnight and headed down to FJRed's place in Waterbury for the pre-NERDS tech day (Wednesday). We did a TBS and a new cam chain tensioner (preventative CCT, no problems). Trying to scope out a possible electrical (ignition problem) we sprayed a little water around coils and wires - no obvious arcing and no additional missing. Poor idle, missing and hesitation plus lack of power below 2000 RPM.

Took the bike to the dealer in Williston (Roadside Marine) on Thursday. In spite of no appointment, they squeezed me in. They did the Gen II wiring recall (S4 not corroded), changed plugs, di-electric greased connections, sprayed the ignition wires and coils with silicone and put some fuel conditioner/cleaner in the gas. They didn't have time to do anything else. It was a little better but still far from right. I also noticed on the ride back to Stowe (and during subsequent rides) that the performance did not change and fuel mileage was down 15-20% from "normal" for my bike.

Rode 300 miles or so on Friday. Still a problem so I took the bike back to the dealer on Saturday - looking for suggestions. Despite the fact that they were busy and had a couple of technicians off, they brought the bike in. They "shot" the exhaust headers with an IR gun and found that #2 appeared to be significantly cooler. They pulled the plugs and #2 was different - darker and the others were white. They re-did the TBS and found it to be pretty good. They had very limited time so they couldn't do much more. The service manager thought it might be a good idea to check out the injectors by swapping #1 and #2 to see if the issues changed cylinders. He did not have a spare injector in stock or I might have asked him to just change it. By the way, kudos to Mike Brisson at Roadside Marine for helping me out without so much as a phone call before I arrived on his doorstep. Didn't even charge me for the work they did on Saturday (1.5 hours)!!

Edit: See post #7 below - possibly NOT a cylinder #2 specific problem!

Anyway, I still have a problem. Poor power and rough at low RPM. Power seems reasonable at higher RPM but with the riding I was doing yesterday (475 miles of slab) I couldn't say if it was normal. Fuel mileage is still substantially lower than normal. I did run some injector cleaner through it for several tanks.

I am looking for suggestions and opinions; either what I can do myself with moderate-to-poor wrenching skills or recommendations for a decent mechanic within reasonable distance (i.e. 400 miles or less) who could look at it and do something in a reasonable period of time. Who has dealt with this before? I have considered the following (in no particular order):

Bad or crapped up injector

Compression (valves or rings)

Skipped tooth on the timing chain sprocket despite considerable care during the CCT change

Crapped up intake (throttle bodies/plates)

The engine is WAY overdue for a valve check but I can't imagine it could be THAT bad or that symptoms would present themselves that quickly.

Wondering if the initial problem was a function of bad gas (particulates, not water) rather than the assumed ignition issue. Also thinking about pulling the fuel tank and having a look to see if there is crud in it.

Thanks

Ross

 

[RadioHowie]

Based, generally, on what you wrote, I'd try several things....one at a time, so I could hopefully eliminate THE problem, rather than do several things at once, and not know which "thing" I did solved the problem, indeed, IF the problem were solved.

Edit to add: Check your air box to make sure you didn't inhale a woodchuck or something.

You mentioning spark plug #2 looking VERY different from the other three, the first thing I'd do is replace all 4 plugs, THEN run through the diagnostic sequence to check coil firing on each new plug BEFORE I screwed the plugs back into the cylinder head. That would eliminate bad plugs AND check the coils at the same time.

Secondly, I'd lift the tank, pull the fuel line off the injector rail and pump a quart or so fuel into a clean glass jar, looking for crap in the gas.

Failing a solution there, I'd pop the valve cover and double/triple/quadruple check my valve timing.

After that, a good afternoon's diagnostics, all bets are off and smarter people than me can chime in. Good luck!

 

[RossKean]

Edit to add: Check your air box to make sure you didn't inhale a woodchuck or something.

You mentioning spark plug #2 looking VERY different from the other three, the first thing I'd do is replace all 4 plugs, THEN run through the diagnostic sequence to check coil firing on each new plug BEFORE I screwed the plugs back into the cylinder head. That would eliminate bad plugs AND check the coils at the same time.

Unless I picked up a woodchuck at 75 MPH, I doubt that's it. I will, however, check out the airbox to make sure the filter isn't too badly splooged up.

Had running problems and all four plugs were changed by the dealer - still had similar problems. I don't think a bad plug is likely (still possible). If it was a bad coil, there would be two cylinders not working.

Thanks

 

[olsonm3915]

Had running problems and all four plugs were changed by the dealer - still had similar problems. I don't think a bad plug is likely (still possible). If it was a bad coil, there would be two cylinders not working.

Not necessarily. It is possible for one coil wire to have a short to earth, which will allow the other wire to fire its plug just fine. This failure mode can even happen inside the coil (unlikely) if that output gets shorted to the coil mounting bracket. Since the bad cylinder is #2 you might have enough slack in the coil wires to swap the plug leads between 2 and 3 to see if the problem follows the plug wires.

Did you run the diagnostic and listen to each injector firing?

After swapping plug leads and listening to the injectors fire I would be getting out my leakdown tester and/or compression tester.

 

[yamafitter]

In diagnostic mode d36 thru d39 fires each injector 5 times. The engine trouble light will flash on each pulse and you should hear the injector 'click'. The sound that you are hearing is the solenoid shuttle valve inside the injector moving and hitting its stop. This tells you that the ECU is sending a signal to the injector and that the coil and shuttle inside the injector is good. What this test does not tell you is whether the injector nozzle is plugged.

It would help to know if #2 plug is 'wet'. This would be an indication of a spark issue. If the injector was plugged this should show as a lean condition and the plug insulator would be white rather than dark. An easy thing to check is pull the plugs and with the plugs grounded to the motor, spin the motor and check the spark intensity. Ideally do this in relatively dark conditions. Spark intensity should obviously be equal. A weak spark might show as a different colour or not as much 'snap'.

Be careful about removing the fuel rail. The o-rings are easily damaged and testing the injector without some type of jig to hold the injector in place could physically damage the injector and spray fuel all over the motor. Not good if you're a smoker.

 

[Geezer]

It still could be one bad plug. I'd try a new plug in cylinder #2 and see what happens. While you are in there make sure the wires is solidly in the plug cap.

 

[RossKean]

I am thinking the problem with #2 may be a red herring. I just checked the pipes with my IR gun and all are reasonably close to each other. At 210 °C, they are all ± 20 ° or so. It is possible that the dealer "missed" when he did it. I had to read them all several times to get a repeatable value. (A thermocouple on the pipe would be more accurate) Either that or the #2 managed to clear itself with no particular improvement in performance. In any case, there aren't huge difference - #3 is slightly lower than the others (going left to right)

Ross

Edit: Power is still poor below 2000 rpm and fuel mileage is poor compared to normal. Idle is rough as well at ~1050rpm. For some reason I cannot bring it up any higher with the idle adjuster screw. Forgot to mention that the technician at the dealer adjusted the throttle position sensor to a slightly higher value. Was 15 or16 and I think he changed it to 18.

 

[RaYzerman19]

Because you mention you can't adjust idle, there might be a vacuum issue. I think you guys did a throttle sync, and did you start by backing out all the screws 1 turn? Regardless, I would re-do it, this time, removing the screws completely, cleaning them off with naptha or lighter fluid or varsol, reinstall by carefully seating them and back them out one turn. Repeat the throttle sync.

Next, inspect the rubber caps to see they are not cracked, and check other vacuum hoses to be sure there are no leaks or disconnections.

I would do all this before playing with spark plugs, coils and injectors...

 

[RossKean]

Because you mention you can't adjust idle, there might be a vacuum issue. I think you guys did a throttle sync, and did you start by backing out all the screws 1 turn? Regardless, I would re-do it, this time, removing the screws completely, cleaning them off with naptha or lighter fluid or varsol, reinstall by carefully seating them and back them out one turn. Repeat the throttle sync.

Next, inspect the rubber caps to see they are not cracked, and check other vacuum hoses to be sure there are no leaks or disconnections.

I would do all this before playing with spark plugs, coils and injectors...

Ray

Good suggestions and probably within my skill set. Unfortunately, I do not have a synch tool but could probably cobble something together with some Tygon tubing and ATF for a working fluid. Are dirty airscrews a common problem? I don't think we started with any particular position i.e. all screws out 1 turn.

I'll do some vacuum leak checking using propane (carefully) + visual inspection. I still plan to check out the condition of the air filter. If downstream seems ugly, I'll probably have a look at the butterflies and throttle bodies. As someone suggested, it might not be a bad idea to have the compression and leakdown checked - hope there's no issue there after only 80,000 km!

Thanks

 

[mcatrophy]

...I do not have a synch tool but could probably cobble something together with some Tygon tubing and ATF for a working fluid....

Many on this forum have made their own. FWIW, mine is described in these pictures.

I find engine oil makes a good fluid, it's self damping and can't hurt the engine if any does get sucked in.

 

[RossKean]

OK, still have MAJOR issues. Decided to summarize and do an action plan...

Current Problem

Very poor power below 2000 rpm with hesitation, jerkiness

Adequate power above 2000 rpm

Excessive fuel consumption (20% worse than normal)

Can't adjust idle speed above 1000 rpm; idle rough!

Problems started while riding in rain on the way to NERDs - don't know if the issue may be wet related but it still exists after thorough drying out

Stuff Done

New CCT installed at NERDs Tech Day. Ty-wrapped cam chain to prevent skipped tooth. Can't see how anything could have slipped

Water misted plugs and coils while running to look for obvious high tension electrical issues

TBS

New plugs

Silicone spray plug wires and coils to displace water and prevent arcing

Dielectric grease various connectors

Gen II wiring recall

Adjust TPS ~15 to 18 (I think, dealer did it)

Checked, cleaned K&N air filter - was OK. No obvious splooge on engine side of filter

Checked ECU connector for obvious issues while doing air filter

Ran multiple tanks of fuel with various injector cleaners, decarbonizers etc. (was a long shot)

Checked temperature of exhaust header pipes with IR gun. Dealer had done it and said #2 was cold but my test (a couple of days later) showed them reasonably close (#3 maybe 20 °C lower @ ~200 °C) Either he "missed" or that cleared itself up without making things better (unlikely)

Next Stuff

Visual inspection of tank for crud or corrosion

Inspect plug ends of ignition wires for corrosion. Snip and re-install if needed.

Check fuel injector main connector + any other obvious connectors

Check for disconnected, loose or cracked hoses/caps for vacuum leaks

Check current position of TBS screws. Remove screws, clean, re-install and begin with 1 turn out

New TBS

After (but soon)

Clean throttle bodies/butterflies

Cam chain timing check

Valve clearance

Compression, leakdown

Injectors, if none of the above solves the issues

Will report back with results. Hope to get most of the "Next Stuff" done tonight.

Ross

 

[ionbeam]

OK, still have MAJOR issues. Decided to summarize and do an action plan...

Current Problem

Stuff Done

Next Stuff

After (but soon)

All of the above, plus we checked all the sensors, actuated all the relays and looked at fault history via diAG. We also fired the coils and injectors via diAG.

The engine runs and sounds like the choke (cold engine FI enrichment from the ECU) is engaged and nothing like a vacuum leak. When Ross rode through the mostly enclosed entry to the Commodore's everyone commented that the smell of gas in the exhaust was so strong that they expected to see the cans dripping gas. Interestingly, the color of the plugs seem to look normal but in this case I wouldn't take that to mean that the engine is not rich. If the engine were excessively rich the temperature of the headers would be close to equal, but low. All I saw used was a home made manometer for the sync so I couldn't tell if the overall vacuum was low or not. If the engine is excessively rich the synch vacuum would be low. Being excessively rich can cause the poor running and low idle speed. One indication that the ECU is in the Cold Run routine would be if the Air Injection Solenoid (AIS) is active. The ECU supplies 12 volts to the AIS to shut it OFF once the coolant thermostat opens, indicating the engine is warm. I have a concern about the intake air temperature reading we saw on the diAG and would like to have Ross go back and look at that again. The values on my '04 are displayed in metric readings.

The engine also has the same running characteristics that would be in keeping with electrical problems in the high voltage secondary ignition system. The engine sounds and runs like one with wet, cracked coils or wires. We tried to check for this but on a crowed tech day I don't think we really got the job done. An ignition scope would put this issue to bed right away.

The engine's poor running is not in keeping with a low voltage problem unless it is a dirty/corroded connector going to the coil's signal wires (solid orange and solid gray wires).

 

[03HiYoSilver]

One thing is to check you Coils and make sure the Tangs are not Shorting out/Bent as seen here:

https://www.fjrforum.com/forum//index.php?showtopic=126721

 

[RaYzerman19]

It might also be a good idea to check the ground spiders, as poor grounds can affect sensors, coils, relays, etc. Especially under the tank, and up on the left side fairing/glove box (may have to remove black inside fairing panel) where water seems to get in easier.

 

[RossKean]

It might also be a good idea to check the ground spiders, as poor grounds can affect sensors, coils, relays, etc. Especially under the tank, and up on the left side fairing/glove box (may have to remove black inside fairing panel) where water seems to get in easier.

The dealer in Burlington VT did the spider recall and said there was no evident corrosion in the one that is augmented. I will have a look at any others I encounter.

Ross

 

[RossKean]

Visual inspection of tank for crud or corrosion - very clean, no obvious rust or sediment.

Inspect plug ends of ignition wires for corrosion. Snip and re-install if needed. - Didn't dismantle but wiggling/moving while engine running made no difference

Check fuel injector main connector + any other obvious connectors - Nothing obvious

Check for disconnected, loose or cracked hoses/caps for vacuum leaks - Nothing found; propane did not cause any idle changes

Check current position of TBS screws. Remove screws, clean, re-install and begin with 1 turn out - Screws were between 1/2 and 3/4 turns out. Tried them all out an additional 1/2 turn. Didn't remove and clean (can this make a big difference?) I seemed to have some ability to change idle speed after that but even at 1200, it was still very rough and still lacked power below 2000 rpm.

New TBS - Wasn't getting anywhere so didn't bother

 

As per Ionbeam, I went to the diagnostic screen and checked intake temperature. Its reading around 100. Warm garage and the bike has only been off an hour or so - seems reasonable?

 

Without ignition diagnostic equipment or any fresh ideas, I'm about done. Perhaps see if the Yamaha dealer in Moncton can earn a fair day's pay. I'm not going to start major dismantling for injectors, throttle bodies etc. unless I have a vey good reason to believe it will get me somewhere.

 

Frustrating, to say the least.

 

Ross

 

 

[olsonm3915]

Check the cam timing,

Riding in the rain could have made the bike run badly, then changing the CCT, even though you zip-tied the camchain, it could have slipped a tooth. That is exactly what happened to my bike when I changed my CCT. I was so sure it hadn't slipped a tooth I didn't check it until I had done a whole BUNCH of stuff just like you. I also zip tied my cam chain but it managed to slip anyhow. My symptoms were not unlike yours, too. I would definitely check it. It's something you can easily do yourself and don't need to have a dealer do it.

 

[RossKean]

Check the cam timing,

Riding in the rain could have made the bike run badly, then changing the CCT, even though you zip-tied the camchain, it could have slipped a tooth. That is exactly what happened to my bike when I changed my CCT. I was so sure it hadn't slipped a tooth I didn't check it until I had done a whole BUNCH of stuff just like you. I also zip tied my cam chain but it managed to slip anyhow. My symptoms were not unlike yours, too. I would definitely check it. It's something you can easily do yourself and don't need to have a dealer do it.

I assume it can't be checked without removing the valve cover? I guess if the timing is off, the valve cover has to be removed anyway...

If this had happened after the CCT without previous symptoms, I would agree that this is most likely the problem. However, sudden issues started while riding - never had problems in the rain before (unless it skipped a tooth while riding?). Similar symptoms both before and after the CCT. I simply don't know and am too frustrated with it now to contemplate another several hours working on it with the very real potential of it not leading anywhere. Maybe I'll hate it less in the morning.

Ross

 

[olsonm3915]

Correct, you cannot check the cam timing without removing the cam cover. It's really not that big of a deal. And if it is off, you need to remove the cam cover to fix it anyway.

I know you said the symptoms started before you replaced the CCT. It is possible, in my mind, for similar symptoms to be caused by two separate things. I may be wrong about it being cam timing. But like I said, I also changed out my CCT and I was totally convinced I could not have had the timing chain slip because I was very careful to tightly zip tie the front and rear runs of the chain together, but evidently that wasn't enough.

I'm also not saying you couldn't have an electrical issue, I like the suggestion someone else gave to check all the spiders (and other connectors too) to see if water got in there and caused a problem.

Good luck.