"Please help if you think you can". I have been without my ski for 6 weeks now, 4 of those have been in the shop of an approver Yamaha dealer,2 were just waiting my turn to get in.
The Particulars:
Only 76 hours on this well maintained and cared for jet ski. i never had a probleb with it and just all of a sudden it stopped running at full speed. It will now do only 30- 32 mph. and only if the throttle is "gently eased up to that speed. Full throttle attempt makes it bog and die. Full throttle attempt from dead stop makes it bog and sputter. Service shop has run compression test, leak down test, replaced impeller against my wishes only to not cure the problem. Theh say they have put a fuel pressure gauge on it while attempting to run it to see if the fuel pump might not be delivering under load and this test proved ok also. The plugs are new this year and just for knowledge are dry when removed (not fouled or soaking wet). They say that they have been able to test the injectors individually and all seen to be functing. I am at a point where I am begging them to try a new "ECU" but I guess that they have to purchase one and if it does not fix the problem then someone has to eat an $800.00 part. I am told it cannot be tested to be good or bad. I am disgusted with Yamaha and the dealer at tis point because right now it has cost me $150.00 an hour to ride this jet ski.Any yhoughts would be very, very appreciated as I own a 1996 waveblaster 3 and a 2003 1300GPR which I purchased the same day as the FX 140 and they run perfect.
Thanks to all who respond!!!
Bill

Bill, I have 190hrs on 04FXHO & I would bet you have a faulty TPS !! Your symptoms are same as I have had 3X previously on other skis,but not the FXHO as yet. These TPS do fail unexpectedly, and easy & CHEAPER to check than an ECU etc etc.
Hope it helps.

Here is a service manual for the FX140

FX140 Service Manual

isn't there a recall or tsb on the throttle bodies for these?

A friend of mine had this same exact problem with his 2003 FX 140. Very well maintained, and it just stopped running full speed.

The dealer was baffled and couldn't figured it out. Eventually they noticed that the gap between the impeller and the pump was a bit excessive, so they replaced the entire rear end (pump, impeller, nozzle, grate - some corrosion) etc... and this still didn't fix it.

Finally I was out riding my '03 FX140 and I sucked up my anchor rope! derr der der I know.. Anyway, I flipped it upside down for about 15 minutes while I cut the rope out... I flipped it back over, waited the 30 minutes that one is supposed to wait after flipping a ski.. then attemped to crank it.. NOTHING!.. after about 15 minutes, it started spuddering and popping. IT finally cranked up and ran like ass for about an hour worth of riding, wouldn't do more than 30mph.
However, I noticed that every time I opened the gas tank, there'd be an enormous suction sound and the cap would pop off. I do know that this happens occassionaly after a lot of riding. But this was happening in 2-3 minute intervals. I'd ride for a couple minutes, shut it down, open the cap, and POP!... I repeaded this about 10 times.
Finally I had it gunned, and for seemingly no reason at all, it just cleared itself up and shot up to 55mph or so (typical top speed).

I explained this to the dealer that had my friends ski, and they said that the ski being upside down created air pockets in the fuel line. Oil could have drained into the intake (somehow) and fouled up the plugs and intake with oil.
My friend then fessed up that his ski had been upside down from a ski rope incident. So they drained the gas tank (removed the air), cleaned up the intake, plugs, wires, new oil change (so the sensor would reset) and then reset the computer...

His ski has never run better...

maybe this helps?

fLoOn

Thanks for your time and input. It is much more serious but I can say that Yamaha was great on Labor day and arrranged for me to have a Brand New FX HO to play with for 3 days. Cant beat service like that. Meanwhile they continue to scratch their heads at mine.
Thanks again,
Bill

These dealers kill me. Both ski's stopped running when going full speed and they decide it's a problem with the impeller . Where do these technicians get their training, at a bubble gum factory?

Wow, interesting. I sold my 04 FX/140 to my cousin a couple of years ago. He had the impeller replaced with a solas. After getting it back from the shop, it seemed to not want to go past 40mph. I told him to double check his order to make sure he got the right pitch on his impeller. He got the right one. Called Riva, they said the dealer that installed the impeller might have overtorqued the nut. He tried to take it back to have the tech recheck it. The tech said no! WTH! No! I couldn't believe they told him that. The tech told him that was the reason he didn't like installing performance parts. Freaking jerk. My cousin being a softee just dealt with it. Now he has a ski that goes 40mph tops.
I am wondering now reading this thread if it even is the impeller? Is there anything else that it could be?
Thanks

Changed the plugs out for him and the ski lives again!
Thanks rockit.

P.S. there was a bit of oil on two of the plugs.

Just so everyone knows--- Yamaha sent their own professional techs to the dealership and they discovered that one of the two coils was failing "Under Load"! Otherwise it worked fine. Took them all summer but I must say that yamahas service was the best that I have ever recieved. The dealer even mis diagnoned the problem and installed a new impeller and then refused to remove it at their cost and Yamaha said "No Sweat and no charge for the whole job complete"! They are the best! Hats off!!!!1

Bill I have to agree with you. Yamaha Customer Service is the best. They replaced my 2000 GPr 1200 Motor at 258 hrs after the crank broke. Replaced it with a new factory motor not a rebuilt one. Motor was still good when I sold it with 453hrs on it. I have the new SHO now. 20hrs with a 5 year warrenty for $400. Can't beat that.

John