Loss of power to one cylinder

[Ottawa]

I have a 2016 fsh190 1.8 liter naturally aspirated engine . Starts perfectly fine and seems to run great until engine warms up. I started noticing some hesitation in the engine power at mid to high range speed, I’d lose power and acceleration. I decided at this point with 50 hours on the engine to replace the plugs and do another water test and add some ISO to the fuel to remove any moisture that might have been in the fuel. After doing this I did another water test and it started up again after the engine warmed up 15 mins of operation high RPM’s . I was still convinced there might be water in the fuel and was told by the dealership using any fuel additives to remove moisture is harmful to the engine because it bonds to the water molecule and is removed during the combustion process , not goood for a high performance engine . So my next step was to pump out and removed all the fuel and put high test in and I did another water test . Still having same issue, hesitation and then complete loss of power. I decided to remove the plugs and notice number one was fowling up. Next step was to check electrical . I did an OHM reading on all coils and they all matched readings also did an OHM reading on the fuel injectors and they were reading same values. I decided to bring them in to the dealership to have them cleaned and tested Thinking number one could be dirty considering I had run out of fuel prior to all of these issues. Dealership said very unlikely and they were right after an expensive test but now I was able to rule them out . iv since done some Resistance checks on the wires leading to the injector and it looks good , I’m now at a loss . If anyone has any experience with this issue any advice would help. On a side note I’m thinking of changing the impeller and doing a ribbon delete , if you have done this with success or no performance gains I’d like to hear about it .

 

[tdonoughue]

Have you done a compression test and checked for spark? I assume since it is good until it gets warm that you will have spark, but the compression test could be useful. If successful test is done at startup, I would run it until it does the same thing and then redo the compression test to see if there is any change. You may have a valve or something sticking at higher temps (I'll admit that is odd).

 

[jtwrace]

https://jetboaters.net/threads/yamaha-1-8l-ho-fuel-injector-connector.26270/

 

[Ottawa]

Have you done a compression test and checked for spark? I assume since it is good until it gets warm that you will have spark, but the compression test could be useful. If successful test is done at startup, I would run it until it does the same thing and then redo the compression test to see if there is any change. You may have a valve or something sticking at higher temps (I'll admit that is odd).

I ended up replacing the fuel injector connector and it worked . looks Like it was a poor connection in the harness. This is a photo from another post that was reporting similar problems on a jet ski . Im in Canada so part was from Benson auto parts ,cost was under $7.00

 

[tdonoughue]

Anytime you can get out with a $7 part, that is a clear win. Nicely done.

 

[Ottawa]

Anytime you can get out with a $7 part, that is a clear win. Nicely done.

I wish I started with replacing the part but unfortunately I started by having my fuel injectors tested at a cost of 170.00. I’ll call it a learning experience.

 

[Ottawa]

Anytime you can get out with a $7 part, that is a clear win. Nicely done.

I’ll still do the compression test on all cylinders so I can have a baseline for future reference .

 

[jtwrace]

I ended up replacing the fuel injector connector and it worked . looks Like it was a poor connection in the harness. This is a photo from another post that was reporting similar problems on a jet ski . Im in Canada so part was from Benson auto parts ,cost was under $7.00

Glad it worked out for you. The pin IN the connector breaks is the issue. Go back and look at my pictures...

https://jetboaters.net/threads/yamaha-1-8l-ho-fuel-injector-connector.26270/

 

[Canuckjetboater]

I ended up replacing the fuel injector connector and it worked . looks Like it was a poor connection in the harness. This is a photo from another post that was reporting similar problems on a jet ski . Im in Canada so part was from Benson auto parts ,cost was under $7.00

@Ottawa .....great information. I always try an electrical continuity test if it may even be slight possibility of a cause as I have seen so many expensive repairs tried when a ground was at fault or a corroded pin. On a big 2014 cruiser I had (full electronics load) I was getting temperature overheat codes. It was under full warranty. I kept suggesting some sort of continuity problem. They replaced a water pump, fuel module impellers, R&Rd the cooling system and were getting ready for some really major work. I was about to leave for a trip and said "stop, I am going to swap the temperature sensor from the port to starboard engine". You know what happened, yes a $25 part after $5,000.00 in parts and labour. Loose wire to one of the pin connections. Full warranty but a PITA for me and a waste of money. My grandfather who owned a heavy machinery rental company used to say "when trouble-shooting start small and work your way up to the expensive parts". With marine parts (and a lot of land vehicles) bad grounds (batteries, ignitions, starters, gauges.....) are causes of all manner of trouble.