2003 stumble when launching

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...How did you measure the voltage on the TPS?...
The whole troubleshooting story is HERE. It includes looking at the gas tank venting, fuel pressure regulator, sensor checks and troubleshooting the TPS. You had replied in another thread about a bad fuel pressure regulator, if the FPR is bad it will set anywhere from 1 to 3 codes in diAG due to persistent fuel injection being out of range. FWIW, only the Gen I FJRs have a closed loop fuel pressure regulator.

 
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Good stuff guys. In will hook my DVM leads into the TPS connector today and go for a ride. The funny thing is, if I have the bike in neutral, just idling and rev the bike, the engine seems to slightly hesitate right around 2000 then revs very cleanly onward.

What do your bikes do? Is the throttle response clean from idle upwards?

Maybe that's just where the mapping switches over. I might just be over thinking my problem and this could just be normal for the FJR.

 
...The funny thing is, if I have the bike in neutral, just idling and rev the bike, the engine seems to slightly hesitate right around 2000 then revs very cleanly onward. What do your bikes do?...
Ohhh, don't go there :lol: In the past we have had people do a large number of odd things with the throttle with the bike in neutral and have been able to create many unexpected (abnormal?) results. The threads go on and on about how weird the idle hunts, revs, sags, exhaust pops, intake manifold pops, etc. I'm sure Yamaha's software and mechanical engineers never expected the engine to be run in some of these situations so it's not surprising that the results were surprising :) Seriously, only worry about normal driving symptoms.

 
Update

Today, I dumped the oil and filled her up with Yamalube 10-40 blended not full synthetic. Also flushed clutch fluids with fresh DOT4. Fluid looked okay - not too bad. The oil was more than ready to be changed out.

What a difference :)

The bike is much easier to modulate the throttle coming off the line and below 2000. I think what my problem was old filthy oil causing the clutch to get grabby. More miles are needed before I will call this one done but I am headed in the right direction.

New TPS will be installed later this week and the combination of the fresh oil, clutch fluid and TPS should get her sorted. Will also put in a new air filter just for giggles too.

 
UpdateToday, I dumped the oil and filled her up with Yamalube 10-40 blended not full synthetic. Also flushed clutch fluids with fresh DOT4. Fluid looked okay - not too bad. The oil was more than ready to be changed out.

What a difference :)

The bike is much easier to modulate the throttle coming off the line and below 2000. I think what my problem was old filthy oil causing the clutch to get grabby. More miles are needed before I will call this one done but I am headed in the right direction.

New TPS will be installed later this week and the combination of the fresh oil, clutch fluid and TPS should get her sorted. Will also put in a new air filter just for giggles too.
More likely the fluid change than the oil, one of the characteristics of the FJR's clutch is poor oil penetration. But, very glad it's riding better.

 
The bike is still not 100 percent as I am still getting some grabbing below 2000 revs. I noticed yesterday when I was putting on the V-Strom hand guards, the master cylinder made clicking sounds coming from the bellows/pin area when the clutch lever was worked in and out. This is not the switch but the bellows where the lever depresses the pin.

This might be normal - not sure.

The other thing is, when I am second gear, slowing down and dropping revs - the bike seems to hold speed and 2000 revs and not drop any lower allmost like it has some sort of cruise control locked on. Idle speed is 1100. The bike has always done this - again normal?

Getting TPS later this week as I ordered this as orignal solution but who really knows
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The bike is still not 100 percent as I am still getting some grabbing below 2000 revs. I noticed yesterday when I was putting on the V-Strom hand guards, the master cylinder made clicking sounds coming from the bellows/pin area when the clutch lever was worked in and out. This is not the switch but the bellows where the lever depresses the pin.
This might be normal - not sure.
You will want to disassemble the clutch lever and check the condition of the brass bushing that pushes against that pin. There are many cases of the pin wearing a hole right through the brass bushing and eventually through the alloy lever.

The other thing is, when I am second gear, slowing down and dropping revs - the bike seems to hold speed and 2000 revs and not drop any lower allmost like it has some sort of cruise control locked on. Idle speed is 1100. The bike has always done this - again normal?
That kind of sounds like what happens to an engine that is running excessively lean. Havew you checked out all the vacuum hoses and nipple caps to make sure you don't have a leak. Also check that all the intake boots are properly seated and sealed on the throttle body. Based on the above symptom, my money is on a vacuum leak somewhere on the intake.

 
Thanks Fred
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Yes, I checked the brass bushing that lives inside the clutch level and its looks great. Gave it a cleaning and a little grease when I was installing the hand guards.

I did check under the tank for cracked vacuum hoses, missing TBS caps and intake boots. They all looked good but I will check again later this week when I replace the TPS and see it I can detect any leaks while the engine is running.

This is fun one for sure and the bike runs great above 2000 revs. Just got to get that low throttle response back and lean running might just be what's going on. I have been reading the fourm postings about the way Yamaha sets up these bikes for lean running right in this range anyway to keep the EPA happy.

 
...I did check under the tank for cracked vacuum hoses, missing TBS caps and intake boots. They all looked good but I will check again later this week when I replace the TPS and see it I can detect any leaks while the engine is running...
Earlier in this thread a method to test for intake leaks was mentioned.

 
Yes, I remember that post and I have a fresh can of WD-40 on hand to spray test. Man, I hope this get things sorted.

 
Yep, if you install a Power Commander on these bikes the cells that require the most fuel addition are in the lower rpm (below 4k and lower throttle openings. Above about 20% throttle most fuel maps actually subtract fuel to hit the stoichiometric target. Then as you get to higher rpms above 4k the fuel additions go to increased throttle openings.

Here's a screen shot of the stock FJR map from DynaJet (I don't run this one) This gives you a good idea where these bikes are running lean with the stock fueling:

StockFJRPCIIIMap.jpg


You can see where I've circled the pattern to where fuel is added vs. flat or subtracted. They got the fueling pretty good if you ran the bike at WOT all the time. ;)

 
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32mpg on my first measured tank so not surprised considering the way the bike runs below 2000 revs. Had a service tech from local dealership test ride my bike and he said it was running great but I am not so sure.

Replacing TPS this weekend and sniffing around for vacuum leaks. Might also check the connector uder the t-bar again and use a little dielectric grease as well just is case. That connector was clean but it was causing my intermittent high beam problem so who knows.

 
...Might also check the connector uder the t-bar again and use a little dielectric grease as well just is case...
I'm in the minority here on the Forum on the topic of dielectric grease. IMO, dielectric grease should not be packed into electrical connectors, it was never designed or intended for this kind of use. Dielectric grease is an insulator i.e. not electrically conductive and it will coat the pins in the connectors with a non conductive film. Use the grease on spark plug boots as a sealant/lubricant, use it on the brass barrel of bulbs like turn signal 1157 bulbs but not on the contacts, it both seals the socket and provides lubrication. This is what it was intended to be used for, though everyone thinks it was made to fill connectors. People have packed their electrical connectors yet they didn't die, nor did their vehicle burst into flames but it is still not a good idea.

 
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Replaced TPS and adjusted 15-99

Checked plugs - fine

Checked for vacuum leaks - none found

Checked electrical connections again and cleaned

Engine seems to be running rich and hesitating right around 2000 revs. Swipe of exhaust pipe showing black soot like carbon.

So, taking her into local dealer tomorrow for a once over and will let you know. Maybe it's the fuel pressure regulator wonky?

 
Bike at the dealer for service showed TBS was off then adjusted and CO emissions were fine. Runs much smoother now and now time to run some Yamaha ring free fuel treatment through her and just enjoy the ride.

Thanks guys for the advice

 
T Pilot

I have an 03 with exactly the same problem, it just started doing a few weeks ago.

I don't ride so much in winter so was waiting to check it out, I thought it might be a fouled plug

or plug wire that overcomes at higher RPM. I noticed if I hold the RPMs at 2K it will run for a few seconds

then miss, then run then miss miss miss then ruuuuunnnnnn the miss etc.

If hope you find a cure and post it, please.

thanks

bunky

 
Well I am glad to know I'm not the only one Bunky :(

My bike is running much better now that I had an TBS done and she's on a diet of Yamalube Ring free fuel treatment. Time will tell but its probably bad gas along with not ridden enough that has possibly clogged or gummed things up.

I also read an article on the 2002 FJR and they said the early bikes had a throttle problem in the lower rev range that made them hard to ride at slow speeds and traffic but that things had been improved on the 2008 bikes - whatever that means. That's why the Power Commanders are popular.

I just keep the revs above 2000 and she's golden.

 
...its probably bad gas along with not ridden enough that has possibly clogged or gummed things up
Spring '12 I had to have the injectors serviced. The fuel stabilizer wasn't enough to keep the crappy ethanol from gumming up one of the injectors over the winter, (#3, iirc). I now use premium unleaded plus yamaha stabilizer during storage.

Anyway, the symptoms sound pretty much the same. The ring free may do the job, but be prepared to pull the injectors and have them serviced. It's an easy job, but to do it properly requires some specialized equipment.

 
Well we surely share some of the same crappy gas silver spirit. Looks like I need to factor in an injector cleaning into my future service plan. Perhaps adding an in-line fuel filter would help out if these injectors are prone to clogging.

Service manual time for me :)

 
Well we surely share some of the same crappy gas silver spirit. Looks like I need to factor in an injector cleaning into my future service plan. Perhaps adding an in-line fuel filter would help out if these injectors are prone to clogging. Service manual time for me
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Just remember, if you DO use an in-line filter, it MUST be able to withstand 40psi of fuel pressure...don't get on of those typical plastic in-line jobs. I've been using one of those fancy-schmancy glass and stainless steel in-line filters for 40+ thousand miles with no problems.

That all being said, an in-line filter won't do **** for ethanol-related clogging...the ethanol isn't a solid substance floating around in chunks in the fuel. It'll pass right through the filter along with the gas.

 
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