There is a loud "howling" type noise similar to blowing in the top of a bottle heard in the area of the throttle body/idle control module.The dealer replace the aftermarket air filter with a Honda filter and the noise isn't quite as loud as it was...there's still that howling concentrated in the aforementioned area.Any ideas?Thanks

The 2004 Suzuki Verona 2.5L does not utilize an idle air control (IAC) valve. Instead, an electronic throttle control (ETC) system is used which Suzuki calls the "main throttle idle actuator" (MTIA). This component is the throttle body assembly but with an internal motor that adjusts the throttle plate open or closed based on accelerator pedal position inputs to the engine control module (ECM). Similarly, the ECM adjusts the throttle plate angle at idle to control idle speed. If the idle speed is not correct, the throttle body may need to be cleaned, calibrated or replaced. You can read more here: https://www.yourmechanic.com/article/how-to-replace-a-throttle-controller-by-mia-bevacqua

Clean the throttle body and idle air control motor. This helps about half the times. The other half would be to replace them. Or live with it. They are still working.

It is usually caused by the air leakage in the intake manifold. Check the following:
1. Check all the vacuum hoses from around the throttle body.
2. Under the throttle body there are three rubber hoses. Two pipes are of the same size and are used for the coolant circulation through the idle air control valve and the third one is a bit thicker than the two. It is used as the air release tube for the idle air control valve, (if the valve is separate from the throttle body). If the idle air control valve is separate type, it is attached to the side of the surge tank, other wise it is fixed to under the throttle body with Philips type screws (4 mm) as a single unit.
3. To locate the intake air leaking source, take a vacant mineral water bottle, fill it with tap water, make a small hole on the cap with a bag sewing needle, invert it and spray water by pressing the bottle with little pressure and pointing it towards a suspected area. If there is any air leaking from around the intake manifold it will produce an audible suction noise. Locate the area and fix it.
4. Remove the idle air control valve, clean and free it up and install it back.

Start the car and use a spray bottle to spray a bunch of water mist around the top back of the engine where the intake meets the head. If it starts to die you have an intake manifold leak. It\'s kind of a pain to change, but not really technical. Also, clean your throttle body and clean the idle air controller (IAC). Alos consider replacing the Throttle position sensor (TPS). Both are located on the back of the throttle body.

Hm first thing you may want to consider when this problem happens is that there may be a vacuum hose disconnected, which will cause a rough idle. If you hear an unusual hissing noise from the engine then get a bottle of throttle body cleaner and spray the area you are hearing the noise from. If there indeed is a leak when the spray hits that area it will surge. A reminder the vehicle must be on when you are doing this test. Next would be the Idler Control Module which is connected to your throttle body, it controls what Idle you vehicle is at when you are at a stop or while coasting. They can get carbon build up usually require cleaning during every 50 thousand miles. Another cause of a high rpm may be related with sensors. An Air Mass Sensor or Mass Air Flow sensor may be full of carbon, which will cause them to malfunction. They tell the computer on the car how much air is coming into the intake so the computer can determine how much fuel to spray in for combustion. My guess out of all this would turn to the Idler Control Module, which you can clean if you know its location and have some tools around.

Hope this Helps!

Your vehicle has electronic throttle control . Position sensor's in the gas pedal an the throttle body , inputs to the Throttle Actuator Control Module
The TAC module is the control center for the throttle actuator control system. The TAC system is self-diagnosing and provides diagnostic information to the PCM through a dedicated serial data line. The TAC achieves throttle positioning by providing a pulse width modulated voltage to the TAC as directed by the PCM.

The throttle actuator control (TAC) system delivers improved throttle response and greater reliability and eliminates the need for mechanical cable. The TAC system performs the following functions:
• Accelerator pedal position sensing
• Throttle positioning to meet driver and engine demands
• Throttle position sensing
• Internal diagnostics
• Cruise control functions
• Manage TAC electrical power consumption
The TAC system components include the following:
• The accelerator pedal position (APP) sensors
• The throttle body assembly
• The throttle actuator control module
• The powertrain control module (PCM)
Accelerator Pedal Position (APP) Sensor
The accelerator pedal assembly contains 2 individual APP sensors within the assembly. The accelerator pedal position (APP) sensors 1 and 2 potentiometer type sensors each with 3 circuits:
• A 5-volt reference circuit
• A low reference circuit
• A signal circuit
The APP sensors are used to determine the pedal angle. The control module provides each APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module with signal voltage proportional to pedal movement. APP sensor 1 signal voltage is low at the rest position and increases as the accelerator pedal is applied. APP sensor 2 signal voltage is high at the rest position and decreases as the accelerator is applied.
Throttle Body Assembly
The throttle body assembly consists of the throttle body, the throttle position (TP) sensors, and the throttle actuator motor. The throttle body functions similar to a similar to a conventional throttle body with the following exceptions:
• An electric motor opens and closes the throttle valve.
• The throttle blade is spring loaded in both directions and the default position is slightly open.
• There are 2 individual TP sensors within the throttle body assembly.
The TP sensors 1 and 2 are potentiometer type sensors each with 3 circuits:
• A 5-volt reference circuit
• A low reference circuit
• A signal circuit
The TP sensors are used to determine the throttle plate angle. The control module provides each TP sensor a 5-volt reference circuit and a low reference circuit. The TP sensors then provide the control module with signal voltage proportional to throttle plate movement. Both TP sensor signal voltages are low at closed throttle and increase as the throttle opens.

Flickering light's could be caused by a bad diode in the alternator . Fluctuating idle could be caused same alternator problem or dirty throttle plate.
Throttle Body Cleaning To Restore Idle Quality

These are all things that can affect your gas mileage and engine performance.

To check for vacuum leak, look for unhooked hoses on top of engine. If OK, use starter fluid and spray along intake manifold gaskets with engine running. If engine speeds up, there is a leaking gasket.

IAC deals with idle. Does the car idle smoothly? If not, remove IAC to see if it's dirty. I will paste instructions below for the IAC valve.

Throttle body dirty--what code is this? never heard of such a code, but you can clean the throttle body wioth carb cleaner. I will paste instructions below.

IAC valve info:

Operation The amount of air taken in during idling is regulated by the opening and closing of the servo valve located in the air passage that bypasses the throttle valve. The servo valve is opened or closed by the activation of the stepper motor (incorporated within the idle air control motor in the forward or reverse direction. Battery positive voltage is supplied, by way of the MFI relay, to the coil of the stepper motor. The engine control module switches ON the power transistors (located within the engine control module) in sequential order, and, when current flows to the stepper motor coil, the stepper motor is activated in the forward or reverse direction.

Removal & Installation

1. Disconnect the negative battery cable.
2. Detach the electrical connector at the sensor.
3. Remove the sensor from the throttle body.
   

To install:

1. Install the sensor in the opening in the throttle body and tighten the sensor.
2. Attach the electrical connector to the sensor.
3. Connect the negative battery cable.

Testing
Checking Coil Resistance

1. Disconnect the idle air control motor connector and connect the jumper (test harness).
2. Measure the resistance between terminal (2) of the connector at the idle air control motor side and terminal (1) or terminal (3). Standard value: 28-33 ohms at 68°F
3. Measure the resistance between terminal (5) of the connector at the idle air control motor side and terminal (6) or terminal (4). Standard value: 28-33 ohms at 68°F
4. If not within specifications, replace the IAC Valve.
5. If within specifications, check connectors and wiring between the sensor and ECM/PCM.
   

Checking Operation Sound

1. Check that the operating sound of the stepper motor can be heard over the idle air control motor when the ignition switch is turned to the ON position (without starting the engine).
2. If no operating sound can be heard, check the stepper motor drive circuit. (If the circuit is good, a defective stepper motor or engine control module is suspected.)

IAC picture--mounted on top side of engine.

Throttle body--loosten clamp to right of throttle body and pull hose off. Use electric parts cleaner or carb cleaner--spray on dirt with engine running. don't touch any sensors inside throttle body--sensors are delicate.

You will need to pull it ,and have it rebuilt. Need to be careful,because they usually don't touch the diff,on a trans axle rebuilt

I would get a reman from the dealer and have a shop R&R yours,then return the core.

I may have had a similar problem, for a long time my blower motor made a loud howling/roaring noise, hard to explain, but I only heard the noise when the blower was turned on. It continued to blow air for a couple years then just quit, the noise it made continued for another 6 months to a year without air-flow. Finally it quit blowing air at all. I eventually replaced the blower motor and no more noise and air flow was restored. Hopefully you already have fixed this because removing and replacing the blower motor wasn't fun.

hi try taking the air filter pipe off the throttle body see if the butterfly spindle has no play in the spindle or the retaining screws that hold it to the spindle have not come loose just put your finger on the butterfly while its idling see if the noise goes if not just pinch the vacuum hose on the vacuum box see if noise goes or changes pitch yates210456