How To Clean A Acuater Valve On A Cumins 360 Engine

Purge valve: how it works, symptoms, problems, testing

Updated September 17, 2021

The purge valve is office of the vehicle Evaporative Emission Control (EVAP) system.
The EVAP system prevents fuel vapors in the fuel tank from escaping into the temper. The EVAP system traps fuel vapors from the fuel tank and temporarily stores them in the charcoal canister, encounter the diagram.

EVAP organization diagram

In mod cars, the purge valve is an electrically-operated solenoid, that is controlled by the engine calculator. When the engine is off, the purge valve is airtight. When the engine is running and fully warmed up, the engine calculator pulses the purge valve open up assuasive some corporeality of fuel vapors to exist purged from the charcoal canister and burned in the engine. When the purge valve operates, it might produce a rhythmic clicking racket nether the hood.

The purge menstruum is monitored by a number of sensors. If the purge flow is less or more than is expected under certain atmospheric condition, the estimator illuminates the "Bank check Engine" light.

Purge valve problems

The most common problem with the purge valve is when it sticks or does not close fully. This may cause the "Check Engine" light to come on. In some cars, a stuck-open purge valve tin cause difficulty starting correct later on refueling at a gas station: for the first few seconds the engine may run rough and stumble.

Purge valve issues are common in many cars. In some Hyundai models (Elantra, Santa Atomic number 26, Tucson, Tiburon), a stuck-open up purge valve is fairly mutual to cause the "Check Engine" low-cal with the code P0441.

Similar problems are fairly mutual in many European cars, including Audi and Volkswagen. In some Ford and Mazda vehicles, a faulty purge valve can cause the code P0446 and other EVAP codes.

A leaking purge valve is not uncommon in some GM vehicles. For some cars, the purge valve warranty coverage has been extended. Google: GM purge valve special coverage.

The purge valve is not very expensive ($35-$65 for the office) and is fairly easy to supersede. In most cars, it'south attached to the engine or the intake manifold. For case, run into this photograph of a purge valve in the Jeep Grand Cherokee.

How the purge valve (solenoid) is tested

You lot can find the proper procedure to test the purge valve in the vehicle's service manual. The procedure is different depending on the car make and model. In most cars, the purge valve is normally closed, pregnant it should be closed with no voltage and open when the voltage is applied.

For case, for this vehicle, the service manual recommends applying battery voltage to the purge valve terminals and run across if it produces an audible click. We just use a 9-volt battery to illustrate. This purge valve does produce an audible click.

The adjacent step, as per the service manual for this automobile is to examination if the purge valve closes properly and does non leak. We connect a manus-held vacuum pump and utilise vacuum to the purge valve.

Near immediately, the vacuum drops. This purge valve doesn't seal properly and must exist replaced. This car had a "Check Engine" lite on the dash. We had it scanned and got the lawmaking P0446 - Evaporative Emission Command System Vent Control Circuit Malfunction. We tested the EVAP organization and constitute that it had a slow leak. At present nosotros accept found the culprit!

To illustrate the difference, we tested the purge valve from a different car. It holds the vacuum very well, even after one infinitesimal the vacuum hasn't dropped.

Now we connect the battery voltage. The purge valve clicks and the vacuum immediately drops. This purge valve is good.

Beside a purge valve, the EVAP-related Check engine calorie-free codes are often acquired by a faulty vent valve or a gas cap.

Source: https://www.samarins.com/glossary/purge-valve.html

Posted by: rodriguezyoughter.blogspot.com

Share this post