Throttle body Leak, poor performance/loss of speed, hard to start, high idle

[Secret Cabin no. 5]

I was having issues with first off loss of speed that gradually got worse and sometimes improved a bit. Then the engine was stalling every now and then when starting. Sometimes rpms seemed to not be stable and sometimes they were. Then the idle went up significantly (near 2000rpm). I spent hours and hours looking for problems and doing research and finally found one little post on Greenhulk about a new throttle body mount from Riva/Worx/or whoever for $85. Solved all issues!

So the issue was a bad throttle body mount that delaminates and lets excess air in that the ECU cannot control as well as loss of boost. This explains the bad idle and then the loss of speed/performance.

The Yamaha mount is a poorly designed part but had a good intention to isolate the throttle body from engine vibrations. It consists of a mounting plate with a rubber section bonded to the metal and the bolts that hold the throttle body do not go through the metal plate and the only thing holding this part together is essential some glue. So it slowly develops small holes and as the engine heats and cools the rubber expands and contracts causing different issues at different times that leads the owner to change out other parts looking for a fix for this issue.

Here is the Riva Part link from Greenhulk: https://www.4-tecperformance.com/in...ucts_id=5506&zenid=93s9vpfmjh4qkt19m9ibk7jdv5

 

[Sublime195]

How many hours before you noticed this?

 

[Secret Cabin no. 5]

About 80-100h but keep in mind rubber fails over time and not just use time. My boat is 2013.

 

[itsdgm]

Great post @Secret Cabin no. 5 did you happen to take any pics?

 

[Secret Cabin no. 5]

 

[haknslash]

Here's a great video as well going over the ribbon delete and the throttle body plate. At around the 1:36 mark he talks about the delamination issue. Never knew of this but its something I'll keep an eye on. They say (on Greenhulk) you can check yours at idle and if you try to move the throttle body from side to side or front to back and if the RPMs go up and down or idle changes it means your throttle body damper is bad. That's what the black plastic piece is called.

 

[njmr2fan]

I'm going to have to check this next time we're out. I've been noting a loss of oomph this season. 2014 AR190

 

[bronze_10]

So this is on the 1.8 not the mr1 correct?

 

[Shannon]

So this is on the 1.8 not the mr1 correct?

Sure is @bronze_10 He has a 2013 SX190 which has the 1.8 engine.

 

[bronze_10]

Whew! Lol

 

[id10tfr33]

ive got a 2019 ar240 1.8 HO throwing intermittent throttle body codes. wonder if this is my issue?