It's not adjustable. Check the Idle Air Control (IAC) valve on the throttle body

First step - have the check engine light or stored fault codes scanned - for free - at any local auto parts store; Advance Auto, Auto Zone, NAPA. Then, post a reply as 'add answer' for more assistance.

Possible Causes of Engine Hesitation or Stumble:

Dirty fuel injectors (cleaning the injectors often fixes this)
Dirty air filter (change filter)
Dirty / clogged fuel filter (change filter)
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)

Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:

Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires

Try this tip.

First, check the battery and starter cables for their tightness or free of corrosion and physical damaged.

See this Starting system simplified diagram. Have a help from an assistant to crank the engine, use a 12 volt light tester or a digital voltmeter, apply it to the starter control circuit.
If there is light or 12 volts and the starter isn't cranking, then the starter is the culprit. Have the starter to bench test for free at the local auto parts stores.
If there isn't no light or no volts, then the ignition switch is the culprit.
Check the starter relay and position the Automatic transmission shifter in neutral.

http://www.samarins.com/glossary/starter.html

Note: a 3/4 charge battery is 12.50 volts
A discharge battery is 11.75 volts.
A battery under a cranking load and it is reading less than 7 volts,it will be a recycled battery.

Fuel mileage would be relative; based on many different factors - such as; vehicle weight, condition (state-of-tune), road speed, weather and wind conditions, tire pressure, wheel alignment, and the list goes on.
Steps to optimize and / or improve the fuel mileage can be found at this website; www.fueleconomy.gov

Just an opinion - harmful not sure, helpful no. What are you trying to solve with this additive? Do you think that the additives that are already blended into today's gasoline are not sufficient? Find the real cause of what you are trying to solve with a liquid that dilutes your gasoline and *there have been rumors* that can cause damage to the filter that is at the bottom of the fuel pump.

In all cases I have come upon in my career when the TB breaks on a Honda the valves bend and that is it. Replace the head, yes you can. Just do a visual after it is apart before committing to buying any parts. make sure there is no damage to the pistons besides the slight indent mark that the edge of the valve makes when the piston strikes the edge of the valve. That mark / indent will not hurt anything.

Ver este sitio para su 2007 Honda Ridgeline 3.5 correa.

http://www.autozone.com/.../...rGuideContent.jsp

Tell us the code number. Have to know any and all fault codes that are stored in the computer. If you want to diagnose this yourself with MY help, I want you to buy a code reader from amazon for $21 and free shipping. Plug in the code reader to the diagnostic connector and read the P codes and then repost with the codes and I will continue.

The radiator cooling fans energize independent of the engine operation. The coolant temperature sensor in the cooling system detects the temperature and signals the fan or fans to engage based on the cooling system temperatures.
First step - check the anti-freeze / water mixture of the coolant - should be at the recommended 50/50. Next step, check the cooling system radiator fins condition - be sure these are not obstructed or blocked to not allow full air flow through. Then, test the temperature sensor - usualy located at the side of the radiator.
Here are several possible on-line auto parts sources; www.autopartswarehouse.com, www.1aauto.com, www.rockauto.com. For example, they (RockAuto) list the cooling system temperature sensor from around $8.00 for your vehicle.

Typically with a high mileage car that has a misfire, i do a compression check for that cylinder and compare it against the rest / and factory standard. If cylinder three is not developing enough compression, then you will have a miss fire. Essentially, an engine is a glorified compression machine. No compression, no power. No power, will equate a miss-fire.

Yes it is possible but the job will be very expensive and will almost never pay for itself and the 2007 Accord book value will plummet.

It leaks when it's on because that's when the coolant is being pumped around the engine and pressure is created due to heating of the fluid. As for why it started leaking without direct hit from the impact, i would say just a mere coincidence....you'd be surprised how many things happen randomly but our brain finds an attributable pattern :)

Well, i would certainly start checking the Fuel Pressure Regulator. I can't think of anything else that could be dumping that much fuel in your intake manifold.

You have mentioned nothing about fault codes, if the engine starts or not. Tell the complete story so we get a feel for what's happening. Just saying gas is in the manifold is nothing to go on when we do not even know if the engine has run and when. If it does not start, have you checked to see if there is ignition spark? Maybe you are losing spark or the timing belt is wrong and it is simply injecting fuel that cannot be used?