Big Power loss below VTEC - Ethanol?

[crxtasy]

I've been having some pretty noticable power loss below around 4K rpm in all gears except 1st. The car sits most of the week and gets driven on the weekends. Sometimes sits 2 weeks, Ive heard there can be separation of the fuel with ethanol. Ive tried to run out the bad gas, but no luck correcting the problem there. No check codes or at least it does light up on the dash.. I probably couldnt outrun an integra right now. It almost feels like the car is holding itself back until it hits VTEC and then lets loose.

I am wondering if I need to siphon the tank and start over. Anyone have any issues like this and if so how did you correct it?

Thanks,
Lee
92 NSX BL/BL
05 RSX-S BL/BL

 

[N Spec]

Have you check plugs or the coils to see if they have water contact/leak?

 

[EdinKali]

Does your fuel there have large amounts of ethanol in it? If so, ethanol does not have as much energy as gasoline in it. I think the rule of thumb was if you ran pure alcohol in your race vehicle you had to use main jets that were twice as large as jets you would run for gasoline. If you can avoid it, don't run fuel that has large amounts of ethanol in it. It can also cause the rubber seals, hoses and o-rings to deteriorate faster.

If you car is as slow as you say it may not just be the fuel. Start with basic troubleshooting(air, fuel, spark). ie, have you replaced your air and fuel filters as required? Might want to check your spark plugs as well and see if you have a strong spark(should be white or bright blue, if it is orange/yellow that is usually a sign of a weak spark).

 

[dablackgoku1234]

Fuel pump maybe? Quoted from another thread...

NSX has a 2 stage fuel pump. Low RPM/idle problems below 4K and if all is well above 4K, as you mentioned, signal to me a fuel pump issue. You can strap out the fuel pump connector in the engine bay above the fuel filter to run at stage 2 all the time to see if that's your problem.

 

[crxtasy]

Thanks, I am going to start with the easy stuff first which need doing anyway and if no luck I will check out the pump. Im going to replace fuel filter, plugs, pump out the tank and refuel.

Ill let you guys know what I find out. Ethanol is known to go bad in Florida in as little as 2-3 weeks so no telling how much water it has in now.

 

[NSXclear]

If your really concerned about it, there is a drain plug at the bottom of the gas tank. Or just drive it like a F1 driver.

 

[Jin1976]

Check the injectors as well. They maybe clogged. Mine I thought it was fuel pump at first as very poor performance under VTEC. Now it run as good as the day I bought the car.

 

[wilsonp]

I've had a similar problem on mine for a while, and the Acura dealership can't find it, but now I think it might be Oxygen sensors, so I bought some NGK to replace them.

Will see if that helps next week.

 

[EIFFEL]

Check fuel pump for proper flow. Sounds like a weak pump.