Awful Engine Noise and Bike Won't Pull (at speed)

[skipperT]

This is a GREAT video which explains some of the basics of the system, straight from the source: 

(I just re-watched it, great refresher...)

-Skip

[betoney]

@skipperT - Great info as usual.  👍

[piotrek]

48 minutes ago, skipperT said:

If you have your CPR9-ea9 plugs still I’d install them before ordering and replacing a TPS sensor. I’ve had experience with 2 bikes recently that had a misfire due to those exact plugs

Hmm... no longer have these, but still cheaper than a new TPS. I recall that the gap on the Iridium plugs was just a hair smaller than the spec.... I left it alone.

52 minutes ago, skipperT said:

reading dropping to .17k ohms around 1800 ohms may or may not be suspect depending on how your meter displays/auto ranges the results

I paid attention to how the meter reads the dip... and it looked legit and repeatable. 'AUTO' on the meter did not flash and scale remained at Kohms.

57 minutes ago, skipperT said:

Remember that with Yamaha TPS sensors 2 of the wires always equal 5 volt reference signal and ECM “clean” ground (blue L and Black/blue B/L if memory serves). The other 2 are the “wiper” signals back to the ECM.

I can only measure the sensor resistance with the setup I have at the moment. The schematic shows wipers W and B as common. Found it odd... but okay.

I appreciate the advice and the dialogue @skipperT. I can't wait to discover that this will turn out to be a simple fix. Fingers crossed.

[koth442]

10 hours ago, skipperT said:

This is a GREAT video which explains some of the basics of the system, straight from the source: 

(I just re-watched it, great refresher...)

-Skip

Super informative video. Great find Skipper!

[skipperT]

17 hours ago, piotrek said:

Hmm... no longer have these, but still cheaper than a new TPS. I recall that the gap on the Iridium plugs was just a hair smaller than the spec.... I left it alone.

good call, iridium plugs aren’t supposed to have the gap adjusted... opinions will vary on that however. 
I checked my spare plug stash today, but couldn’t locate my old ones to shoot off to you to try (you’re in Canada too IIRC...) I have one more place to Che k for them...

Quote

I paid attention to how the meter reads the dip... and it looked legit and repeatable. 'AUTO' on the meter did not flash and scale remained at Kohms.

definitely pointing to a bad spot in the sensor then...

Quote

I can only measure the sensor resistance with the setup I have at the moment. The schematic shows wipers W and B as common. Found it odd... but okay.
 

that’s special stuff from the “department of redundancy” department. It was explained to me that is how “they” keep it (YCC-T) “safe” for the rider. any disagreement beyond a programmed amount between the 2 sensor wires will result in the system going to idle and a CEL. 

Quote

I appreciate the advice and the dialogue @skipperT. I can't wait to discover that this will turn out to be a simple fix. Fingers crossed.

No worries, hope you figure it out. Keep us posted. 
-S

Edited April 28, 2020 by skipperT

[piotrek]

~ SOLVED ~

@skipperT hammers it into the net, and @phpaul gets the assist. Gone are the iridium plugs and so is the problem. Thank you.

I first ran the re-flashed ECU through all the diagnostic tests (all checked out great), and then rode the bike with the iridium plugs. Sure enough... the issue resurfaced, with no error codes. Replaced with NGK CPR9EA-9 and the bike sailed past 7,000RPM without a hiccup. For interest's sake... photo of the two electrodes below. I don't recall having this problem before later last year, with the plugs at ~30K kms. I will stick with the stock plugs. NGK rates them at 30K miles.

[Toddtr]

1 hour ago, piotrek said:

~ SOLVED ~

@skipperT hammers it into the net, and @phpaul gets the assist. Gone are the iridium plugs and so is the problem. Thank you.

I first ran the re-flashed ECU through all the diagnostic tests (all checked out great), and then rode the bike with the iridium plugs. Sure enough... the issue resurfaced, with no error codes. Replaced with NGK CPR9EA-9 and the bike sailed past 7,000RPM without a hiccup. For interest's sake... photo of the two electrodes below. I don't recall having this problem before later last year, with the plugs at ~30K kms. I will stick with the stock plugs. NGK rates them at 30K miles.

All that mess and headache over a set of plugs. Just remember K.I.S.S. 

[tktplz]

6 hours ago, piotrek said:

~ SOLVED ~

@skipperT hammers it into the net, and @phpaul gets the assist. Gone are the iridium plugs and so is the problem. Thank you.

I first ran the re-flashed ECU through all the diagnostic tests (all checked out great), and then rode the bike with the iridium plugs. Sure enough... the issue resurfaced, with no error codes. Replaced with NGK CPR9EA-9 and the bike sailed past 7,000RPM without a hiccup. For interest's sake... photo of the two electrodes below. I don't recall having this problem before later last year, with the plugs at ~30K kms. I will stick with the stock plugs. NGK rates them at 30K miles.

And now I know not to waste my money on expensive plugs on the FJ. She apparently isn't high maintenance.  😍

[skipperT]

9 hours ago, piotrek said:

~ SOLVED ~

@skipperT hammers it into the net, and @phpaul gets the assist. Gone are the iridium plugs and so is the problem. Thank you.

I first ran the re-flashed ECU through all the diagnostic tests (all checked out great), and then rode the bike with the iridium plugs. Sure enough... the issue resurfaced, with no error codes. Replaced with NGK CPR9EA-9 and the bike sailed past 7,000RPM without a hiccup. For interest's sake... photo of the two electrodes below. I don't recall having this problem before later last year, with the plugs at ~30K kms. I will stick with the stock plugs. NGK rates them at 30K miles.

So glad your problem is fixed, Piotrek! Woo hoo, redline again!

-Skip

Edited May 17, 2020 by skipperT

[2and3cylinders]

I had been monitoring this thread with significant interest. I'm glad it was resolved with minimal $ outlay if not time and aggravation.

Pio & Skip, do you only tip down the radiator to swap plugs, rather than go the hard route?

Coincidentally, until I recently checked valve lash (after finding all valves very tight at 24k miles) even though it had been only about 10k miles because it'll be out of its 4 year YES warranty in late June, I had been running the same iridium sparkers.  As it always bothered me the reach of the iridiums was short of the OEM plugs, I popped in fresh OEM.  Now I'm very glad I did.

You may recall a couple of years ago I posted about a equally weird seemingly deviant electrical gremlins I had after installing the ECU also flashed by Dave.  It ran fine but but when blipped at idle, it would hang up at around 2100 briefly before dropping to normal.  I took it for an extended shakedown run, and of course about 45 miles from my shop, during a high speed run to verify the 114 mph limiter was off, all sorts of heck broke loose.  The over heat warning popped on, the tacho disappeared, and other weirdness occured.  I immediately stopped under a shade tree. Then turned around and stopped again at a close by taverns parking lot and checked that the also newly installed APE MCCT was still adjusted  close (I check them by ear [after initial installation when checking/adjusting valve lash and plugs] while hot and running).  The MCCT seemed OK and the overheat warning disappeared but the tach and other data was still blank except intermittently while I limped back to the Bret Cave.  I then ran many checks, posted a query thread up here, and basically was in a funk.  Then, when deciding to dig deeper, and intending now to also pull the air box, when I started to unplug the ECU's small plug, it came out with only a gentle pull before I had depressed it's detent!  Doh! Stupid, stupid, dum, dum!  I had not ensured the plug was fully seated and engaged.  For all of you, my mistake is your gain.  I had not followed the KISS principle.  

[skipperT]

42 minutes ago, 2and3cylinders said:

Pio & Skip, do you only tip down the radiator to swap plugs, rather than go the hard route?

I had not ensured the plug was fully seated and engaged.  For all of you, my mistake is your gain.  I had not followed the KISS principle.  

I usually perform the sync at the same time, so I go through the top. Dropping the radiator is a fast way too, and then you don’t need to pull the tank. I find it easier to yank the PAIR hoses and disconnect the valve and move it out of the way, rather than fight the limited access. That easier from the top.
To each their own, right?

There’s an expression/rule that I always keep in the back of my mind when troubleshooting electrical:

-70% of the time it’s a connection, 30% of the time it’s the component.

-skip

[2and3cylinders]

Since my ECU flash disabled the PAIR valve, I flipped the PAIR system exhaust inlet reed valve stops & HTRTV silicone sealed the reeds themselves down (a procedure I learned many moons ago when PAIR systems first appeared as a poor man's alternative to block-off plates), capped and sealed the reed valve inlets as belt & suspenders, and last time under the hood I finally removed the PAIR valve and hoses altogether, and taped up the plug. Consequently, access to the spark plugs with the radiator tipped down is very easy for me.  I also connected vacuum hoses to each TB port nipple and extended and secured the hoses to up behind the left frame spar near the steering head.  Each hose end has a capped nipple. So in 2 minutes I can check TB sync by simply connecting my remote hoses to my ancient mercury vacuum gauge without touching the bodywork and tank.  I posted pics of this previously.  I plumb sync hoses like this on all my bikes, even those with carbs.

I also concur with your rule of thumb. I simply forgot it because my memory has gotten just terrible in the last 20 years (also discussed in other threads herein), and my power of recall has NEVER been strong as it was...

[piotrek]

3 hours ago, 2and3cylinders said:

...I had been running the same iridium sparkers.  As it always bothered me the reach of the iridiums was short of the OEM plugs, I popped in fresh OEM.  Now I'm very glad I did.

This was a seemingly legitimate upgrade (better performance, longer life etc.). There is a thread on here somewhere with NGK sales rep (🙄) claiming compatibility, so several members switched over at maintenance time. There was no reason to expect issues... and there were none for a year. Should have trusted their selector tool... and Yamaha instead. I have come across spark plug/coil/distributor failures in the past, but this was a completely new thing to me. The engine sound and the loss of pull, and the set of conditions involved was a head scratcher. Should've, could've... whatever. Good lesson... won't forget.

[2and3cylinders]

Yes, I went to that particular precious metal (literally and figuratively), fine wire electrode because I read the same supposed NGK OK and its advantages (other than cost).  Until then I had followed on finding something else AMAP and discovered NGK does offer an iridium plug for the CP3 but only in Indonesia or thereabouts.  I called the primary US distributor for NGK, and he concurred it's listed (with the same dimensions as the conventional plug) but for some reason not available anywhere else (and was also puzzled).

[nhchris]

Great news the problem is solved @piotrek

What I'd like to know is the WHY of it.

What caused the iridium plug to fail after 12 months? And what actually failed within the plug? 

Huuummmm.