t-rd

I recently started seeing some idle related problems. My milage is higher now at 63K; a 98 Accord V6. The rpm would sort of go up and down when the car is cold, also warmed up idle seems a bit rougher than before. I think I need to clean the throttle body or the intake manifold since my ignition system is in check. Has anyone done this yet?

My main questions on this subject is:
- Do you have to remove the throttle cables? (throttle and cruise control cable). My understanding is that when you spray carb or throttle body cleaner in, you should keep the throttle plate open. There is no way of doing this unless someone holds the gas wide open (probably not good at idle in Park); or remove the throttle cables so that the rotor can be freely moved.
- Is it hard to remove the throttle cables?
- What kind of cleaning fluid did you use? I heard of people using regular carb cleaner and some use Gumout.
- How did you clean it? I've heard of methods by having the spray sucked in through somehow into the TB or intake manifold. Some simply sprayed fluid on a cloth, wrapped it around a screw driver, stick through and wiped inside.
- What components should I watch out to not spray the cleaner on? I know there is a TPS sensor and IAC (Idle Air Control) unit nearby.

Any help is appreciated,.. thanks.

t-rd

Ok, I just answered one of my own questions. The throttle plate can be swung freely while the car is off by moving the throttle rotor manually. This does not move the gas pedal or the cable itself. The throttle cables bend, but do not crunch up to cause damage. I managed to get my finger into the very inlet of the intake manifold and it is totally BLACK with carbon deposit!

Can anyone answer the rest? Thanks

Lawaia

Get a can of 3M Throttle Plate and Intake Cleaner. Stuff is awesome....plain and simple.
Also, if your throttle body is that dirty, you got a crappy air filter. You may want to change it (or service it - re-oil) at the same time.

johnnyb_s

Any throttle body cleaner will work. Keep in mind though that if you clean it while the car is off, it will have a hard time starting and will run rough until all the throttle cleaner is burned up. What I do is have the car running and spray some in until it is about to cut off, then let it burn through that and do it again.

t-rd

That means you need to run the car without an air filter when you are doing this? Won't that be bad for the engine?

My throttle body/intake manifold is dirty from the carbon deposit not because of my air filter though. There is minimal dust but lots of carbon deposit.

johnnyb_s

It doesn't hurt to run the car without a filter for a few minutes, which is all you are going to need when cleaning it with the throttle body cleaner.

Lawaia

Yeah...it don't hurt until you suck in a piece of debris that you thought wouldn't ever happen. My suggestion is to follow directions (difficult for some people) which is first and foremost Turn engine off. You'll be glad you did.

johnnyb_s

You do know that there is such a thing as being too safe...anyways, everyone is entitled to their opinion.

Bitium

It's mostly from the EGR/PCV valve and not from the filter. Stock filter does not get re-oil. You replaced them.

EGR Exhaust Gas Recirculation
PCV Positive Crankcase Ventilation.

The vehicle components that are responsible for reducing air pollution. This includes crankcase emissions; evaporative emissions and tailpipe exhaust emissions. Crankcase emissions consist of unburned fuel and combustion byproducts. These gases are recirculated back into the engine for reburning by the Positive Crankcase Ventilation (PCV) system. Evaporative emissions are the fuel vapors that seep out of the fuel tank and carburetor. They are prevented from escaping into the atmosphere by sealing the fuel system and storing the vapors in a vapor canister for later reburning. Tailpipe exhaust emissions consist of carbon monoxide (CO), unburned hydrocarbons (HC) and oxides of nitrogen (NOX). This formation of these pollutants is minimized by various engine design features, careful control over fuel calibration and ignition timing, and the EGR system. The pollutants that make it into the exhaust are "reburned" before they exit the tailpipe by the catalytic converter. The emission control system is an integral part of the engine, and should not be tampered with or disconnected. This is especially true on vehicles with computerized engine controls and/or those that must be subjected to mandatory emissions testing.

Acura charges about $150 to do this.

1) Take the throttle body apart from the manifold and clean it. I could be done with a any throttle body cleaner. You basically clean the butterfly and the surroundings

2) They apply a Intake Cleaner to clean carbon monoxide from the manifold. This is done by a very little tip connected to a hose and placing the hose in the cleaner bottle. Then you connect the tip to the brake vacuum hose on so it gets suck into the manifold. This is done with the car on.

Or take it to the acura dealer and pay $150 :wow:

t-rd

What Bitium described was sort of what I read. I think I'll just take it to Honda and let them do it right. If I try to do it myself with simple cleaner, I can only clean the TB up to a point. I do not want anything to be sucked into the intake; I do not want to damage any electronic sensors or the IAC motor; and I do not want the intake manifold cleaner to be sucked through the wrong hose. I'll spend the money and have a peace of mind.

Bitium

I took the whole manifold out one time. Man that thing was so black. It was funny, because I spray a lot of throttle cleaner in tha manifold, it was doing its job, but when I pickup the manifold to let the fluid out onto a plastic cup, then when I turn around the plastic cup was melted :wow: some powerful stuff.

t-rd

Bitium,
I just scheduled a service with Honda to do this. Honda charges only $90, but Acura charges $150 as you described. I thought it's not bad since I never ever cleaned it in almost 5 years! I attempted it myself but only could get so far. My throttle plate and gas pedal stick pretty bad sometimes depending on the weather, all due to carbon deposit. This should be $90 well spent.

Bitium

Yeah I did it for $45 at the USMC base in SC.

$90 is a good price. According to my mechanic, the stuff they use is almost $50 bucks. I'm guessing Honda is using the same stuff. $40 for labor is pretty good.