2002 225 4 stroke high idle and back fire

[egreenwood]

I have a 2002 yamaha four stroke that had sat for 2 years. The water had gotten in the fuel system and gummed it up. I replaced both fuel pumps all filters and water seperators. As well as the housing emptied and cleaned the fuel tank. Replaced all the injectors. Cleaned the vst tank. And replaced the inline check valve. I also replaced the spark plugs. But for some reason it idles at like 1600 rpms and back fires through the intake. Now there seems be fuel in the oil. If anyone could please help me I would greatly appreciate it. I have replaced everything I can think of and the shops are so expensive.

[Finisher]

Check to see if your throttle plates are closed fully. There are link rods on top that can hang up and make that happen. Did you adjust anything by the intakes? The backfiring may be from high idle so solve the idle problem first. Does it hold at 1600 or surge?

[seahorse5]

That motor had 2 different Coast Guard recalls for sticking throttles. See a dealer and find out if both recalls had been performed, if not, let them do it for free. Giving the dealer the complete model and serial numbers allow them to access the Yamaha database to see if the recalls have been complied with.

Other problems can give the high idle, but get the recall information first.

[egreenwood]

It does surge a little bit. The top 2 butterflies are open more than the rest so i will try to do that. would that explain the fuel in the oil? also the bottom two intakes seem to be pouring out a very little bit of oil i guess from the back firing. Thanks for your help guys.

[Finisher]

No fuel in the oil with that model and year can be a few thing like a corroded head. Leak down test the heads. Or compression test but leak down would be better.

[morayinc]

I had a high idle and surging same model. The iac was bad. Listen for it to reset "chatter" at key off. If that sound is missing look there. Removed from the housing you can see it actuate key on then off.

If the butterflies are out then you may need to consider having them synced. This is kind of involved do a search for it under "rodbolt17".

[Finisher]

I had a high idle and surging same model. The iac was bad. Listen for it to reset "chatter" at key off. If that sound is missing look there. Removed from the housing you can see it actuate key on then off.

If the butterflies are out then you may need to consider having them synced. This is kind of involved do a search for it under "rodbolt17".

Totally agree but that still would not solve your gas in oil problem. Make sure the engine can run right before you fix the bugs. A bad head or bad midsection could mean lots of money. But the ISC can and will do that.