What causes a Honda Accord to idle erratically?

What causes a Honda Accord to idle erratically?

This article is for a hunting or erratic idle, the original idle speech was for a ‘shaking’ or ‘rough’ idle. For that, check out the other link about Honda idle issues. Step 1, check for air in the cooling system. This is the most common cause of an idle issue on Honda’s. Especially if you just serviced the cooling system.

What to do when your Honda Idles down?

If you’re sure you don’t have any vacuum leaks, and you’ve bled the air out of the cooling system, and you still have a problem, then check the IAC (Idle Air Control valve). You can do this by tapping on it with the butt of a screwdriver while the engine is running. If the idle changes or stumbles in some way you may need to replace it.

Why does my Honda Civic idle too high?

When cold you just get an idle that is too high like up around the 1200-1500rpm range or higher. The second video shows a vacuum leak that I found on a Civic using a ‘safer’ method for checking for vacuum leaks. Both work but the important thing is that you check for vacuum leaks if you have a Honda idle problem.

Can a PCV valve cause an idle problem?

I’ve actually seen aftermarket PCV valves cause idle problems in some cases, usually a rough idle. The PCV valve is actually a controlled vacuum leak so if it’s not calibrated correctly it can cause idle issues. So if you’re running an aftermarket PCV you might want to exchange it for an OE unit.

What does fast idle thermo valve do on Honda Accord?

The fast idle thermo valve (FITV) controls the idle at cold starts. It keeps the idle high and gradually decreases the idle as the car warms up. These three parts should be taken out and cleaned. If they are beyond cleaning and repair, they should be replaced.

Why is my Honda Accord stalling when I let off the gas?

If you have a Honda ( or any other car) that has a very low idle or is stalling out when you let off the gas, it probably has a gummed up idle air control valve. It is really easy to fix this problem by removing the idle air control valve and straying carburetor cleaner into the valve.

Why is my Honda Accord running at a low idle?

Vacuum leaks add too much air to the mixture causing the engine to run lean. The computer also fights them as it tries to maintain an idle using the IAC but it can’t keep up so you get a ‘hunting’ idle condition meaning that the idle fluctuates from high to low and it never levels out. This condition is often worse after the engine warms up.

If you have a Honda ( or any other car) that has a very low idle or is stalling out when you let off the gas, it probably has a gummed up idle air control valve. It is really easy to fix this problem by removing the idle air control valve and straying carburetor cleaner into the valve.

If you’re sure you don’t have any vacuum leaks, and you’ve bled the air out of the cooling system, and you still have a problem, then check the IAC (Idle Air Control valve). You can do this by tapping on it with the butt of a screwdriver while the engine is running. If the idle changes or stumbles in some way you may need to replace it.

When cold you just get an idle that is too high like up around the 1200-1500rpm range or higher. The second video shows a vacuum leak that I found on a Civic using a ‘safer’ method for checking for vacuum leaks. Both work but the important thing is that you check for vacuum leaks if you have a Honda idle problem.

What happens when the PCV valve fails on a Honda?

Usually if the PCV valve fails in this manner, you’ll experience a ‘high’ or ‘hunting’ idle. An easy way to find one of these faulty PCV valves is to pinch off the supply line to the PCV valve with a pair of pliers while the engine is at idle.

What causes the RPM to fluctuate while idling?

It might be the intermittent failure of an idle speed solenoid. They go by a bazillion different names and have just as many variations. For example: Et cetera… It may also be, as noted in your comments, an air leak somewhere. Seeing as how it works fine above a certain RPM, I’d be willing to bet it’s an idle speed solenoid of some type.

What are the symptoms of a bad idle air control valve?

Below are the top 5 symptoms of a bad idle air control valve which you will easily notice. Since the idle air control valve is supposed to manage the idle speed of the engine, a bad valve will certainly throw that out of whack. It will cause the idle speed to randomly fluctuate to different speeds rather than stay at one constant speed.

When to idle air control at 1000 rpm?

Idle air control..it should idle at 1000 rpm’s when the engine rpm’s jump up and down,suspect the iac. Thanks for contributing an answer to Motor Vehicle Maintenance & Repair Stack Exchange!

What’s the normal idle speed for a Honda Accord?

Around 800 rpm is normal sometimes if your intake manifold is dirty the computer doesn’t manage it right so it feels like your car is choking it gets as low as 400 rpm then you just have to remove your intake and clean the inside of your manifold

When does the idle air control valve change?

When the engine is running but the vehicle is not moving, this means the engine is idling. During this time, the number of revolutions per minute (RPM) inside the engine will change. The idle air control valve is responsible for managing the engine idle speed.

Why is the idle speed of my car so high?

Step 2 – The idle air control motor (valve) is responsible for controlling the engine idle speed, if this part fails or becomes weak the engine idle speed could become erratic, additionally, this condition may or may not trigger the MIL (check engine, service engine soon light.)

What causes the idle surge on a Honda?

Inside the valve is a wax pellet (just like a thermostat) that opens and closes a vacuum line that allows additional air to bypass the closed throttle plate at cold idle. The fast idle valve has a reasonably high failure rate. When the valve fails, it causes idle surge. Here’s how to check it out.

What to do when your Honda engine is idle?

If you’re sure you don’t have any vacuum leaks, and you’ve bled the air out of the cooling system, and you still have a problem, then check the IAC (Idle Air Control valve). You can do this by tapping on it with the butt of a screwdriver while the engine is running.

Why does a 4 cylinder engine have a rough idle?

In fact, in the end it may still be there to some degree because of the nature of a 4 cylinder engine. 4 cylinder engines fire every 180º of crank shaft rotation. Because of this, the crank spends a LOT of time in rotation before the next power stroke. This creates a ‘choppy’ power delivery that may be most noticeable at idle.

How to clean an idle air control valve in a Honda Accord?

Remove the Honda idle air control valve. Unscrew the 2 bolts attaching the IACV to the intake manifold. You will have to feel around for the lower bolt, which will be just out of plain sight. Pull out the gray plug from the right side of the Honda IACV. Remove the blue plug from the throttle body.

How can I tell if my idle control valve is working?

To check if an idle control valve is working properly, start by turning on your engine and letting it run for a minute or 2. Then, when it’s at an idling speed, take note of the RPMs in your car. Next, turn the engine off and disconnect the idle control motor under your hood.

What should I do if my idle control motor is disconnected?

The engine should still start and run without any issue despite the idle control motor being disconnected. Be sure to tuck the wiring you disconnected up in the engine bay so it doesn’t get caught in any moving parts. Look for a difference in idle speed.

Where is the IACV located on a Honda Accord?

Locate the IACV. You will find it at the back center of the under hood area, near the throttle body (TB) and mounted on the rear of the intake manifold (IM). You will have to remove the TB intake hose in order to gain access to area of the IM that is connected to the IACV.