• 2021

Replacing an Exhaust Gas Recirculation Valve

2001-2010 CHRYSLER PT CRUISER

The three main emissions from an internal combustion engine are hydrocarbons (HC), carbon monoxide (CO) and oxides of nitrogen (NOx). HC and CO are relatively easy to control compared to NOx. There are a few strategies used to control NOx, but the most common one is the use of exhaust gas to cool the temperature of combustion. This is done because NOx formation is the direct result of high combustion temperatures. Exhaust gas is redirected into the intake gases through the use of the exhaust gas recirculation (EGR) valve. Based on the operating conditions at the time, a solenoid is energized to allow the flow of exhaust gas back into the intake stream.

EGR VALVE BASICS

The EGR valve consists of three components: ① the EGR valve, ② the EGR solenoid, which controls the opening/ closing of the valve, and ③ the tube that connects the EGR valve to the intake manifold runner. Figure 1 shows a typical EGR valve assembly that has been removed from the engine (Note: The tube is re-used).

Figure 1

Figure 1

The EGR valve is mounted on the end of the cylinder head next to the exhaust port on cylinder #4. One end of the tube is mounted on the EGR valve, 90 degrees from the valve mounting bolts. The other end of the tube is mounted to the upper intake manifold. The solenoid is mounted under the throttle body. Two rubber hoses are connected to the EGR valve.

When you first look into the engine compartment, the EGR valve and solenoid are not visible; however, the upper mounting point of the tube on the upper intake manifold can be seen. It is on the back side of the engine. The tube descends to the right side. Follow it to locate the EGR valve. The valve and solenoid, though, are only easily visible and accessible with the air cleaner box removed from the engine.

PROBLEMS WITH THE EGR VALVE

If you have a vehicle of a certain age that requires an emissions inspection every year or two, this valve must be operating properly in order for the emissions test to be passed. The PT Cruiser, built between 2001 and 2010, is a great example of this type of vehicle. Many of these cars are still on the road and require emissions checks.

Commonly, the valve itself becomes clogged with exhaust byproducts. One of three conditions can result: (1) the valve is stuck in the open position, or (2) the valve is stuck in the closed position, or (3) the buildup of byproducts restricts the flow of exhaust gases through the valve. The usual DTC message will concern itself with the improper flow of exhaust gases. When such a message is stored, the EGR valvemust be replaced. This type of problem will prevent the vehicle from passing the required emissions test.

EGR VALVE REMOVAL

The most efficient method to remove the EGR valve assembly is to first disconnect the tube at the upper mounting point (see Figure 2), then remove the EGR valve with the tube still attached to it. This will allow you to mark the location of the correct tube orientation on the new valve. The tube must be oriented in the same way it was on the old valve.

Figure 2

Figure 2

Note the flange and tube in Figure 1. These are two separate pieces. Once the two bolts are loosened, the tube can be moved to any position. When the old valve is removed, note the orientation so when the tube is transferred to the new valve, it can be oriented in the same location. It will save you a lot of time on the installation of the new valve.

Let’s begin the removal process. In order to access the EGR valve, the air intake hose and the air cleaner box, located on the RH side of the engine compartment, must be removed (see Figure 3). Once removed, the EGR valve can be seen. There are two mounting bolts that secure the valve in place. Remove these bolts. Then, remove the upper mounting bolts for the tube (see Figure 2).

Figure 3

Figure 3

Next, remove the EGR solenoid, which is located just below the opening to the throttle body. This requires two
steps. First, disconnect the electrical connector. Then, pull forward on the solenoid to pull it from the rubber grommet.

With the upper mounting tube bolts removed from the intake manifold, the mounting bolts removed from the EGR valve and solenoid unplugged and unsecured, all three components are loose, but are all connected to one another. Lower the solenoid down to the EGR valve and push those two pieces toward the firewall between the engine and fuse box. The tube will move backward with the valve. Then, go around to the passenger side of the car and pull up on the tube. As you pull up with one hand, reach down with the other hand to grab the valve and solenoid. Remarkably, the entire assembly can be pulled up and out of the engine compartment.

EGR VALVE INSTALLATION

The new EGR valve assembly consists of a new EGR valve, two valve mounting bolts, a thin steel mounting gasket and a new solenoid with two rubber tubes. The rubber tubes are connected to the EGR valve. The EGR tube, mounting flange and mounting bolts are not included and must be re-used.

When the EGR tube is removed from the old valve, it must be installed and oriented in the same position as it was when the valve was removed. Notice how it is oriented in Figure 1. Make alignment marks on the tube and old valve before the tube bolts are loosened. Remember, the tube and flange are two separate pieces. Make a mark on the new valve in the same location as on the old valve.

Remove the two tube mounting bolts and remove the tube from the old valve. Align the mark on the tube with the mark on the new valve and install the mounting bolts. Be sure the marks are aligned before the bolts are tightened. The EGR valve assembly will look just like the old assembly when it was removed from the engine.

From the passenger side of the car, lower the valve and solenoid down between the firewall and engine. Mount the EGR valve on the side of the cylinder head by aligning the two valve mounting bolts with the bolt holes in the cylinder head (see Figure 4). Before installing the bolts, locate the solenoid. Push the tab into the grommet to secure the solenoid in place, then connect the electrical connector.

Figure 4

Figure 4

A new steel gasket is supplied and must be installed to prevent exhaust gas leakage. In order to hold the gasket
in place, place a drill bit or short nail in each bolt hole. Push the valve against the head, remove one drill bit
and install the bolt. Then, install the second bolt after the drill bit is removed. Thread the bolts approximately
3/4 in. Align the EGR tube with the upper mounting location and thread those two bolts approximately 3/4 in. Once the valve and tube bolts are installed and both pieces are in place, tighten all four bolts.

To complete the replacement procedure, reinstall the air cleaner box and reconnect the air intake hose on the throttle body opening.