KrZy8 Hissy Fit - KeyBoard Techs Needed!

[Bounce]

Odd. Works for me.

[dcarver]

2020-11-27 - Rough Running Fixed

For I have met the enemy, and he is I.

Some worthless .02 cent tech forgot to fully snap this connector together.
Was preparing to remove injectors then test fire, with tank connected, via Diagnostic Screen.

Went to wiggle injector #1 connector, and the big gray connector came apart.

SIGH.

"It's really hard to be perfect." (Steve Burket)



Here's what she sounded like when sick.

[wheatonFJR]

Awesome. Glad I could help!

[raYzerman]

Dammit Carver, if you had told us in the first place, we coulda helped better sooner! You're lucky Wheaton was on it.

[escapefjrtist]

Great news DC, glad the 'ol gurl is running again! You need to have a talk with your "tech".

~G

[dcarver]

Well CRAPOLA.

The ride today went from running good to bad to great to barely starting, huge stumble off idle, 23 mpg to 41 mpg.

I still haven't found the root cause problem.

[dcarver]

https://www.ebay.com/itm/2006-Yamaha-Fj ... Swbdxc2xpj

Hmmm

[raYzerman]

Did you check the MAP sensor nipple and vacuum line were clear?

[dcarver]

New to me injectors arrived.. and FI harness and air box sensor await pick up tomorrow.

Been busy sorting the Kz1300 and Cbx.. and only one lift.. LOL. My life is good.

https://candybuttorg.ipage.com/cba/node/950

[FJRoss]

Make sure all the residual crap is out of your tank before trying the new injectors!!

[dcarver]

For Pics...
https://candybuttorg.ipage.com/cba/node/939

Unhappy day. Sigh.
Reflashed ECU from Ivan's Performance.
New TB from eBay.
Starts easy and runs good to 4k then massive popping in exhaust, both sides.
No ECU error codes.

Installed new to me eBay, 17k mile TB assembly. Running diagnostics, #2 injector didn't click when activated. After several attempts, yes she fired up. Not unusual for an injector that's not been run for awhile.

Ran diagnostics on TPS. Low of 17, max per FSM is 15. And 104 at full throttle, should be 100.

So crap. The best I could adjust was 14 and 101. Can I do better? Have 4 other TPS units at hand...

Let's measure them out with an ohmmeter..
<Results to follow>
Found one with very close to specs, and 15, 100. Installed.

Position 1 and 2, as shown, is from the 'wiper' and full scale end of the poteniometer.

I used the best one I had per FSM specs. It set perfect at 15, closed throttle, and 100, full throttle. Repeatable.

Mounted the tank, fire KrZy8 up and she ran!

But not very well at first, expected. Been there before.. with engine swap, took a minute or so for the fuel rail to charge, discharge air, then she was happy. Not today.

Anything above 4k rpm sounds horrible. Both exhausts pipe... Missing... which to me indicates not ignition, but fuel delivery? Runs great at idle, 2k, 3k.. but 4k+ and popping...

So replaced new to me FI injectors with old, refurb injectors from RC Engineering.. same result.. so not injectors..

Thinking either fuel pump failing (OEM, 2006, almost 250k miles = aLOT of gallons pumped) or clogged FP screen, or fuel pump relay. Discounting ignition issues as both exhaust stacks have the same 'miss' at 4k and above..

Next thoughts..

1. Use 2013 gas tank/fuel pump see if problem goes away (fuel pp on 2006 bad, clogged, etc)
2. Change spark plugs, JIC
3. Shoot the bitch and be done with it?

Ideas, team FJR Peeps?

[ionbeam]

One small thing to contribute -- the TPS if just fine with any of the readings you got, statically on the bench. The TPS receives a zero and +5 volt reference voltage from the ECU. Note that zero and ground are not necessarily the same because it is a reference voltage and not a utility voltage like lighting or instruments. The wiper of the TPS will return a 0.7 to 5 VDC to the ECU that is proportional to the throttle position. The ECU does an A/D conversion, then does some math on the voltage to convert the voltage to % of throttle opening. When you see 15 to 17 it indicates the ECU thinks the throttle is 15% to 17% open which it needs in order to idle (the 0.7 volts equals 15% and ≈ 4.8 volts equals 100%). The bottom number will change with idle speed adjuster screw in addition to the turning calibration of the TPS body so there is no real, absolute number. If you want to play, try the idle speed adjuster, this is why you can't get the numbers you want (but don't really need anyway). Turn down the idle speed adjuster and the TPS percentages will drop down. A reading of 101 to 104 indicates the ECU thinks the throttle is 101% to 104% open. The ECU will clip anything over 100%. The range between the bottom number and the upper number is fixed, you can't make the difference larger of smaller, you can only shift the whole thing up and down. Ideally, you would set the idle speed then adjust the TPS. But, as soon as you do a TB sync and then move the idle speed the TPS will be off again. Lots of words to say don't sweat a few % error of the TPS reading.

The TPS is one of several things the ECU looks at to determine the FI shot and ignition timing. As long as the TPS voltage is stable and tracks the throttle the TPS is a minor player in the FI/ignition mapping. If the TPS is non-linear by having drop-outs which exceeds some programmed limit the ECU will react by going into the fuel-cutoff routine. As soon as the TPS passes the damaged portion of the resistor and returns to a normal reading the ECU will have a slight pause (to be sure you really mean the throttle increase) the jumps the FI/timing map back up again. This is the same as abruptly chopping off the throttle then whacking it wide open. It's a rough ride when that happens but it is transient. Importantly, it will happen at the same exact throttle opening, regardless of gear once the engine is warmed up. This is one of the best indications of a TPS failure. My TPS had two drop-out points, one just off idle at around 1,700 RPM and again around 3,000 RPM where it predictably demonstrated the TPS failure.

Given where DCarver lives it isn't unlikely that the sock on the fuel pickup may be clogged. However, this would be more likely to show up as weak performance as the RPMs climb. Usually the fuel pump works yes or no but not maybe or not at a certain RPM unless there is a voltage glitch to the pump motor. The ECU monitors the voltage to the pump and the voltage can statically be seen via diAG. Since Dave has a second tank and the swap is simple it could be done just to verify the pump isn't the problem.

IMO (which may not be worth much) a hard failure at predictable engine speed points to an electrical problem. The only exception may be a carbureted engine from the 80s & 90s that had an emissions bump at 4k RPM as the carb transistion from the idle jets to the main jets.

[dcarver]

Audio Link. It will make you grimace..

https://www.dropbox.com/sh/s6ot1mhwth1w ... pXcGa?dl=0

[ionbeam]

Audio Link. It will make you grimace..

https://www.dropbox.com/sh/s6ot1mhwth1w ... pXcGa?dl=0

Not TPS. Nope, definitely not TPS.

[dcarver]

Audio Link. It will make you grimace..

https://www.dropbox.com/sh/s6ot1mhwth1w ... pXcGa?dl=0

Not TPS. Nope, definitely not TPS.

Thank You ionbeam. Appreciate your advice/input.

[dcarver]

Found the fuel pp relay by activating diag code 50, listening, then feeling. It at least clicks which means not much.. but location is verified.

[HotRodZilla]

Audio Link. It will make you grimace..

https://www.dropbox.com/sh/s6ot1mhwth1w ... pXcGa?dl=0

Is there any chance your timing is off a tooth? WTF?!?! Your fueling is FUBAR. Corrosion in a plug? How are your spiders? Pinched wire? When's the last time you changed or inspected your air filter and unplugged that main harness? Any chance a connection in there is bent or broken?

[FJRoss]

You already knew that the fuel pump relay works at least some of the time - otherwise it would never run at all.
The diagnostic test identifies which is the right relay so that's good.
Relay might be an issue or wiring/connections to or from the relay. This was the front end that got Bambied a number of years ago.
Flakey fuel pump relay (or fuel pump) might do this. Check the pressure on the fuel rail.
You might want to try some of the wire wiggling/voltage measuring that 1911 did when he had issues. Might want to move that harness around some while running the engine.

Still can't see how it could be timing if it runs well at least some of the time. That audio clip sounded like a pretty sick motor but if it skipped a tooth, it wouldn't run right any time.

Did you compare the temperatures of the four pipes where they come out of the engine using your fancy new IR camera or a temperature probe? Or use a contact thermocouple which would be more accurate. Will quickly tell you if all are the same. No point in comparing left vs right at the exhaust pipes - system is 4 into 1 into 2.
I concur with Ionbeam - no way a slightly flakey TPS could do this. Not unless it was FUBAR.

[raYzerman]

About valve timing being off... it may run just fine until 4-5000 then not develop horsepower after that, or at least very slowly. Usually no popping though, and idle may hang up rather high (2000) before settling down. I'd guess retarded a tooth in that case. Can't speak for advanced, usually not the case.
So let's ask, if timing was OK last time you had the valve cover off, did it run OK then? Was there any time since then the CCT was backed off and chain not zip tied at the crankshaft? Unfortunately the only way to verify valve timing is to pull the valve cover (coolant drain and all that jazz).
Have you checked right timing cover has not pinched the ignition pickup wiring that goes up the front side? That will cause some of the crap you're seeing. Pull the clips and ensure the harness is not trapped, particularly at the top of the timing cover.

[dcarver]

Audio Link. It will make you grimace..

https://www.dropbox.com/sh/s6ot1mhwth1w ... pXcGa?dl=0

Is there any chance your timing is off a tooth? WTF?!?! Your fueling is FUBAR. Corrosion in a plug? How are your spiders? Pinched wire? When's the last time you changed or inspected your air filter and unplugged that main harness? Any chance a connection in there is bent or broken?

I don't think timing is off. This is a binary problem. When running good, it's freakin' good. Then BAM, gone. Plugs are new. Spiders have been replaced with Brodie's harness. Air filter is new. ECU harness recently inspected and female sockets look clean, straight, OK.