HPDI Yamaha Problems

I have an 06' 250 hpdi Yamaha on a Blazer Bass boat. So far it has had an electrical problem, oil pump replaced, now the ECU has went out as well. Has anyone else had any problems with these engines? This motor has only 50 hours on it. I have always owned Mercury engines in the past, but I was convinced this engine was "the" engine to have.....I am beginning to think that this was a bad decision to purchase a Yamaha.

Re: HPDI Yamaha Problems

wow, that is odd. never saw an ECU fail on an HPDI, a few injector drivers on the old single driver setup.
what kind of Electrical issues are you having ?

Re: HPDI Yamaha Problems

My dealer called Yamaha, he indicated that the ecu on certain models would cause this erractic running and cold starts when trying to start engine. Do you think this would cause that? Also, would the oxygen sensor cause these symptoms as well?

Re: HPDI Yamaha Problems

you really really need to find a dealer.
yours seems a bit off.
the Z250 doesnt use an O2 sensor.
its not hard to simply monitor input and output voltages to isolate an issue.
last VZ250 I got had been to two other dealers and the issue was a pulser coil over voltage.
by that time I had to correct the original issue and some technician induced issues.

Re: HPDI Yamaha Problems

Would you happen to know a good reputable Yamaha technician in North Georgia? Any help would be greatly appreciated!!!!!!!

Re: HPDI Yamaha Problems

www.yamaha-motor.com/sport/dealers/dealerhome/home.aspx

try this site and type in your zip code.
what your looking for is a dealership with a master tech.
if ya cant find that at least find one that has certificates on the wall for the fuel systems and electrical systems at a minimum.
if they dont have that keep searching.

Re: HPDI Yamaha Problems

rodbolt took motor to shop because it was running hi idle came back as an injector code swapped injector drive still high swaped ecu still running on 4 cyl and will excellerate in nuetral been working on this for eight hours ready to have a breakdown

Re: HPDI Yamaha Problems

rather than have a breakdown simply learn how the 3.3L Z motors work.
you have been chasing a non problem as in N that engine idles on 4 cylinders by desighn, above about 1500 in N it runs on 2 cylinders,by desighn.
high idle can be caused by a code set,TPS set incorrectly or a throttle shutter not properly adjusted.
just because an injector code is set does NOT mean an injector had an issue.
low high pressure fuel can do it as well.
your either going to have to take a crash course in HPDI systems,yamaha isnt the only manufacturer to try it, EFI systems as some of it overlaps and a couse on electronics diagnostics.
either that or you will find poke n hope is expensive.
test the operation of the nuetral switch on the shift slide.
thats why in gear it runs on 6 and out of gear it runs on 4.
the oil pump was an update. ECU failure I have not seen on that engine but it could happen.

Re: HPDI Yamaha Problems 2001 200Hp

Re: HPDI Yamaha Problems 2001 200Hp

Originally Posted by Rainman09
New to Forum but I've read all posts I can find on this motor. Bought used motor that ran OK for about 1 hour then problems developed. At 3800rpm motor begins to die/stumble if I give it any more throttle. Replaced Lift Pumps, VST pump filter, all filters prior to VST replaced, Medium pressure filter between VST and Mechanical pump replaced. Fuel pressure at 3800rpm is 56 psi in VST and YDS says 700 at Mechanical Pump. Any more throttle and the pressure in Mechanical pump drops below 600psi while VST pressure remains at 56psi. Does this sound like the filters in the Mechanical pump OR are there other serviceable parts in the Mechanical pump? I have the pump removed but have not taken it apart to look at the filters yet. If there are other serviceable parts in the pump then I need to send it to Flagship. I'm assuming that if they clean it they not only replace filters but all packing kits as well.


The guy that connected the YDS also removed fuel vent and return lines from VST tank to check them before we lake tested the motor. If they were reversed when reconnected could this be a possible cause for the pressure drop in the mechanical pump ? One of the lines "T's" to the starboard side of motor the other goes to a solid pipe on Port side which faces forward. Which hose is return and which is vent and which fitting on the VST forward or rearward gets vent (or does it matter).

Any help would be appreciated ...thanks

Re: HPDI Yamaha Problems

Apparently you did not read the top post before posting this.
It is best to start your own thread instead of adding to some one else's older one.http://forums.iboats.com/showthread.php?t=250876