Spark plugs replacement

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Yendaa

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Hi guys, just a quick question. The place where my bike is being serviced diagnoses the problem: "Problem with fuel map sensor and throttle bodies, requiring full clean and decarbonise .

Replacement spark plugs also required ".

I have replaced spark plugs 10 000kms ago. Is it really necessary to replace them again when the bike was starting up normally or they just want to use more parts to make more money? Thanks in advance.
 
What "fuel map sensor"?

I would like to see a picture of the throttle bodies. I know they (butterfly plates, in particular) get carboned up but i never really heard of a running problem. What is (or was) your bike doing?
I see from your introductory post that you have a 2007 with 122,000 km?

The following might not apply to your bike!!!
For that model year (early Gen II), I am wondering if this started out as a problem with start and idle and a Fault Code 14? Not a "Fuel Map sensor" but a MAP (Manifold Absolute Pressure) sensor. Yamaha calls it a pressure sensor. You might want to read the following thread. Once I had the tank up and the top of the engine accessed, the fix didn't take more than a half hour but of course it took longer than that to figure out. (mine was also a 2007). If I saw that error again, I would know what to look for and the fix would take me an hour from beginning to end. (It has happened with a number of Gen II bikes that I have heard about.)

https://www.fjrforum.com/threads/fault-code-14-gen-ii-solved.170314/
There was nothing wrong with the sensor, just the goo in the line. Problem never recurred as long as I had the bike (sold at 295,000 km) and has not happened on my 2011.

Oh, and welcome to the forum!!
 
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If you feel they're doing it to rip you off then go get your bike back. But you asked them their opinion and the minimal cost of replacing spark plugs is part of it. You want them to be thorough, doncha? Well, they are. Pay them for that. Good tradesmen never cut corners, pay them for that.
 
What "fuel map sensor"?

I would like to see a picture of the throttle bodies. I know they (butterfly plates, in particular) get carboned up but i never really heard of a running problem. What is (or was) your bike doing?
I see from your introductory post that you have a 2007 with 122,000 km?

The following might not apply to your bike!!!
For that model year (early Gen II), I am wondering if this started out as a problem with start and idle and a Fault Code 14? Not a "Fuel Map sensor" but a MAP (Manifold Absolute Pressure) sensor. Yamaha calls it a pressure sensor. You might want to read the following thread. Once I had the tank up and the top of the engine accessed, the fix didn't take more than a half hour but of course it took longer than that to figure out. (mine was also a 2007). If I saw that error again, I would know what to look for and the fix would take me an hour from beginning to end. (It has happened with a number of Gen II bikes that I have heard about.)

https://www.fjrforum.com/threads/fault-code-14-gen-ii-solved.170314/
There was nothing wrong with the sensor, just the goo in the line. Problem never recurred as long as I had the bike (sold at 295,000 km) and has not happened on my 2011.

Oh, and welcome to the forum!!
There was an error code 14 shown.
What "fuel map sensor"?

I would like to see a picture of the throttle bodies. I know they (butterfly plates, in particular) get carboned up but i never really heard of a running problem. What is (or was) your bike doing?
I see from your introductory post that you have a 2007 with 122,000 km?

The following might not apply to your bike!!!
For that model year (early Gen II), I am wondering if this started out as a problem with start and idle and a Fault Code 14? Not a "Fuel Map sensor" but a MAP (Manifold Absolute Pressure) sensor. Yamaha calls it a pressure sensor. You might want to read the following thread. Once I had the tank up and the top of the engine accessed, the fix didn't take more than a half hour but of course it took longer than that to figure out. (mine was also a 2007). If I saw that error again, I would know what to look for and the fix would take me an hour from beginning to end. (It has happened with a number of Gen II bikes that I have heard about.)

https://www.fjrforum.com/threads/fault-code-14-gen-ii-solved.170314/
There was nothing wrong with the sensor, just the goo in the line. Problem never recurred as long as I had the bike (sold at 295,000 km) and has not happened on my 2011.

Oh, and welcome to the forum!!
There was an error code 14. The bike sometimes stall right after I started it up and I had to hold the throttle open to keep it running. Now I got the message saying the work is done. They are saying that they've spent 4h30 mins by fixing it and asking 420 EUR for it, seems as a ripoff to me. According the research I did, the rough time to get it done is around 2hrs in total. They've done this on the bike:

- Inspect bike

-Plug in diagnotiics

-MAP sensor fault

- Remove tank, air box etc.

- Inspect MAP sensor - Found carbon build up in sesor and

throttle bodies

- Remove and strip and clean sesor

and throttle bodies - Replace spark plugs

- Reassemble, test ok
 
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Did you read the thread I linked?

No plug in diagnostics on Gen II but you can get to the fault codes via the LCD display - no special equipment required. Causes are described in the service manual.
What I had was some sticky deposit that blocked the line from the sensor. Easily cleaned up once I found it. Don't know what they mean when they say "Strip and clean sensor".
As mentioned, carbon buildup on throttle plates may look bad but doesn't usually cause catastrophic running issues.

Edit: Read the following for access to and descriptions of fault codes
https://www.fjrforum.com/threads/diagnostic-codes.9612/#post-117762
 
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Does anybody have an idea, how long does it roughly take to do the jobs on this job sheet? They charged for 5hrs of labour, it's too much in my opinion. Thanks
 

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2007 Model Year

Inspect bike - anywhere from 2 minutes to a half hour, depending on what they are doing. Perhaps just start it to reproduce your problem.

There ARE NO plug-in diagnostics. As mentioned before, fault codes may be read from the LCD dashboard. Takes 10 minutes, if you know what you are doing.

Remove trim, tank, T-bar, thermal shielding - maybe 15 minutes.
Airbox another 20 minutes (but probably not necessary).

Inspect MAP sensor? No idea what they did. Possibly a visual inspection. Give it 10 minutes to remove it.

"Carbon" buildup. Typically, you find some sort of organic goo in the sensor line, not in the sensor. Easy to clean the hoses - remove and use solvent (let dry before reassembly).

The Throttle Bodies are a separate issue. Yes, the butterflies get "carboned" up. Removing the throttle bodies and cleaning them may be quite time consuming - some people have documented that service on this forum. I doubt they would have a major impact on running, but that is just my opinion. Certainly, they did not cause your root Fault Code #14 and difficulty starting/running issue. (At least not the primary cause.)

Replace spark plugs - once the engine is accessed, this takes 15 minutes, tops.

Reassemble - half hour?


The biggest single time eater would be the remove and clean throttle bodies and the time taken would be proportional to how they did it and how bad they were.

Having experienced the Fault Code #14 before, I would have checked the diagnostics using the link I posted previously, lifted (not removed) the tank, remove t-bar and tank insulation, removed and cleaned hoses to MAP sensor, changed sparkplugs, checked operation, and reassembled in less than a couple of hours. It took me a great deal longer than that the first time when I had no idea of the likely root cause. Depends on their knowledge and experience. Note: I would not have done the throttle bodies unless they were really bad.

With the throttle body cleaning, I still think five hours is a bit much, but it depends on the experience of the mechanic. Not wildly out of line. The only question is if they did stuff not needed - a matter of opinion. Much of what I have said is pure speculation. I can't really comment further since I did not actually see what they encountered.
 
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I think the problem is that you asked for help here AFTER the bike was already in the shop being worked on. The shop has done work and has to be paid for what they did. Seems from the other posts this could have been taken care of in your driveway.
 
In 5 hours I could do the valve shims, replace the cam chain tensioner, R&R the TB rack to replace the starter motor and do a TB sync. Sounds like a long time to clean some gunk out of a vacuum hose. "Cleaning the throttle bodies" may have happened but I also question the necessity. It's not like they are carburettors with tiny passages that get plugged and restrict fuel flow. They are just 4 big air valves.
 
In 5 hours I could do the valve shims, replace the cam chain tensioner, R&R the TB rack to replace the starter motor and do a TB sync. Sounds like a long time to clean some gunk out of a vacuum hose. "Cleaning the throttle bodies" may have happened but I also question the necessity. It's not like they are carburettors with tiny passages that get plugged and restrict fuel flow. They are just 4 big air valves.
5 hours???!!! 😯I need about 2+ days for these jobs!!! 🙂😂
 
In 5 hours I could do the valve shims, replace the cam chain tensioner, R&R the TB rack to replace the starter motor and do a TB sync. Sounds like a long time to clean some gunk out of a vacuum hose. "Cleaning the throttle bodies" may have happened but I also question the necessity. It's not like they are carburettors with tiny passages that get plugged and restrict fuel flow. They are just 4 big air valves.
the blade edges are what need to be decarbonized......
 
5 hours???!!! 😯I need about 2+ days for these jobs!!! 🙂😂
I'm assuming they are all done in one session -- eg: the tupperware has to be removed, tank, t-bar removed, etc. then reassembly of everything only once if it's all done at the same time. And I've found a few short-cuts over the years -- eg: the manual says the left fairing panel has to come off to drain and refill the A/F, but it doesn't -- things are flexible enough you can gently pull the panel back sufficiently to access the rad cap. If you are strictly adding up "book hours" for each job individually, then yeah, it'll take longer.
 
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