2003 200hp 4 stroke

[stevelouk]

I have a 2003 200h 4 stroke on a grady white, bought new in 04. was going out to fish and running 5200 rmp perfect as always and it shut off. re-started turned around to go back in and could not run over 7-8 miles per hour with out shutting off, had to limp in, have had a master-tech working for several weeks, everythings check out good still not running without sever miss firing issues, please help --no one in the area has had this problem

thanks

[99yam40]

need to know if it is spark or fuel problems.

My guess is fuel .

Easy to monitor fuel pressures and vacuum on the suction side to look for restriction.
But he should be doing this already, and the shop should have the equipment to flow test your system even without the motor running

[stevelouk]

thanks

I will check with the machinc I have working on her thanks for the info and trying to help me, this is killing me

[rodbolt17]

I am a Yamaha master tech and you can look it up on the Yamaha website or look at the wall at the shop.

the F200 uses a stupidly simple speed density EFI system for fuel delivery and an equally stupid TCI ign system.

monitor fuel pressure at the failure RPM and load.
use the Kv tester to monitor spark on each cyl at the failure RPM and load.

not all techs/shops have a Kv tester and fewer understand how to use it.

[stevelouk]

thanks

I will tell the guy working on my motor that, thanks, sure is killing himself and myself with this

[stevelouk]

problem solved

My tech finially found the problem, it was the idle control valve which controls several systems including the O2 sensors and idle and firing system, it was a $400 part and lots of labor but he only charged me a lot less than he had in it.

[rodbolt17]

biggest 2 issues I have with that.
the F200 has no O2 sensor.
the ISC circuits don't connect to any other sensor circuits.

[stevelouk]

my words not his

I might have used the wrong terms to the units it controls; however it was the idle control valve that he replaced and all is well, I am going for a test run today to verify that all speeds are good.

[stevelouk]

code 29

also it was a code 29 that the computer showed but that could indicate several things and would not clear until he replaced the idle control

[rodbolt17]

code 29 indicates a malfunction of the intake air pressure sensor which can make the engine run stupid but its not connected to the ISC circuits.
intake air is a 5v circuit and ISC is a 12v circuit.