F250 idle

[chaserfish]

hi all, i have a 2006 F250. normally the idle speed is 600 rpm.the engine will start and run at 600 rpm. after the engine is put in gear and run it will not idle down below 800 rpm when put back in netural.if the engine is shut down and restarted it will idle at 600rpm. anyone have any thoughts on this problem. thanks

[boats.net]

Needs to be checked with computer diagnostic, fast idle could be because of a fault code.

[chaserfish]

thanks for the reply.is there a scan tool you can use to check the codes or do you need a laptop with software and usb cable.

[boats.net]

Unless you have the Yamaha Command Link gauges then will need to be taken to a dealer to have diagnostic run on it.

[chaserfish]

i had the engine hooked up to YDS and it showed no faults. the only thing the mechanic could find was carbon build up it 2 cylinders.doing carbon treatment and adding ring guard to fuel.

[rodbolt17]

its broke.
have it fixed or have the lower unit fixed later.
the laptop typically only shows whats not wrong.
use the yamaha dealer locator function and find a master tech.

[chaserfish]

i don't need anyone to tell me it's broken no s___. just trying to get some info. any master tech's here?

[99yam40]

Rodbolt is one, just need to ask the right questions, and give the info needed.
The read out that they got on YDS would probably help

[chaserfish]

any help is appreciated. i would like to know the proper way to troubleshoot this probelm. the tech i used i have had no probelms with but he can't seem to put his finger on the probelm so far. he did a YDS scan and bleed down test. engine has 800 hrs and runs fine other than the idle going between 600-800 rpm. if i knew the proper way to go about finding this probelm. it might be helpfull. i can bring it to another tech or try to work thru it with the one i have been using. any suggestions or anyone that has had the same probelm could help. any insight on this probelm would help. the service manual says (trouble code not detected)high engine idle speed(below 1200) cause is air leakage. checking step. check o rings on intake,surge tank and throttle body.
any suggestions on this or where i can find someone to fix it in SE MASS. thanks

[99yam40]

Service | Yamaha Outboards

like he said find a shop with a master tech
Did you get a print out of what the YDS showed?

Showing what all the readings were when checked might give info needed

[chaserfish]

the tech i used is listed on the locator? thanks for the reply. i can get a print out but maybe take it elsewhere.

[rodbolt17]

has anyone checked the throttle cable and adjustments?
yes any air leaks can cause high idle.
do you have comand link guages?
typically the laptop only tells me whats not wrong.
vacum leaks can be detected using the laptops map readings.
its actually quite simple if the tech understands manifold absolute pressure.

[chaserfish]

thanks for the reply. no command link guages.checked the cables first then ran the YDS.i am going back to the tech on monday to keep trying.it is very hard to get someone to work on your boat this time of year so it doesn't make it any easier. i run offshore and use to boat a lot so having this probelm is killing me.any suggestions are appreciated. thanks

[rodbolt17]

could be an air leak could be an inrange sensor failure.
compare the data saved when its idling at 600 RPM then again when its idling fast.
the data save will disply about the last 13 minutes of engine operation in 1 min intravels.
what your looking for is what changed.

[chaserfish]

thanks for the reply.inrange sensor failure is something the tech said hopefully we are on the right track.i know there are a number of sensors any idea of what one it could be or the one to check first. will compare readouts. thanks again.