Fix It

Engine problems in Jeep Liberties have led to a safety recall due to the possibility of engine fires. On July 2, 2004, DaimlerChrysler Corporation and the National Highway Traffic Safety Administration announced a recall of 1,600 Jeep Liberty vehicles for engine problems.

Engine Defect

Certain Jeep Liberty sport utility vehicles equipped with 3.7L engines were recalled for engine-related manufacturing defects that could lead to serious problems. Two valve cover studs on these vehicles could interfere with the fuel injector and alternator wiring harness, according to NHTSA.

Safety Risk

Due to this safety hazard, the NHTSA warns that a fire could start under the hood as a result of damage to the alternator wiring harness. Registered vehicle owners were notified of the safety recall beginning July 19, 2004, and instructed on where to bring the vehicles for repair to avoid the risk of a fire.

Solution

Authorized dealers were instructed to add protective caps to the valve cover studs and re-route the affected wiring harness to provide clearance, according to the manufacturer and NHTSA. Consumers who purchased second-hand vehicles or who are otherwise concerned about whether they may have been affected by the Jeep Liberty engine-related recall may contact the NHTSA for more information. Refer to recall number 04V337000.

Removing the EGR valve from the 2.8-liter diesel engine in a Jeep Liberty can be time-consuming. Fortunately, with a little effort and a lot of patience, you can do it yourself and save on an otherwise large repair bill. The EGR valve is located on the back of the engine, just below the intake manifold on the drivers side of the engine. The valve bolts in place with four 8-millimeter bolts that are hidden below the manifold, so you will not be able to see them.

Instructions

1

Open the hood of your Jeep and locate the negative battery cable on the battery. Loosen the pinch bolt with a wrench then lift the cable off the battery and set it aside.

2

Position a catch basin under the passengers side of the radiator and remove the petcock from the radiator tank, allowing the coolant to drain from the system. Once the coolant has stopped draining, replace the petcock.

3

Remove the bolts from the top of the engine cover on the engine, using a socket and ratchet. Lift the cover off the engine and set it aside.

4

Locate the EGR valve on the back of the engine near the drivers side head. Remove the clamps from the cooling lines on the EGR valve then pull the two coolant lines off the valve.

5

Remove the four 8-millimeter bolts from the EGR valve with a wrench then separate the valve from the engine block. A ratcheting wrench may be necessary to remove the 8-millimeter bolts.

Installation of a new catalytic converter on your Jeep Liberty will improve the engine performance of your Jeep. If the converter becomes plugged it can over heat or limit the engines ability to breathe by limiting the flow of exhaust out of the engine. The converter is an important part of the exhaust system and while they are expensive to replace, they are necessary for the engine to run properly. Be sure to allow the exhaust to cool if the Jeep has been running before you start working on it. The pipe and converter get very hot when the engine is operating.

Instructions

1

Locate the front mounting flange from the front exhaust pipe for the catalytic converter. There are two bolts that secure the flange from the converter to the flange on the pipe.

2

Position the catalytic converter so the two flanges line up, insert the gasket between the flanges and insert the retaining bolts. Install two nuts on the mounting bolts and tighten them with a socket and ratchet or wrench.

3

Insert the mounting rod on the converter into the hanger under the cross member located near the center of the converter. This hanger is a rubber hanger that the mounting rod slides into.

4

Slide the tail pipe onto the output pipe on the rear of the converter and install the band clamp. Tighten the clamp with a socket and ratchet until it is tight but do not over tighten it or you will crush the pipe.

5

Start the engine and check for leaks in the exhaust system. If you find a leak, tighten the clamp or bolts needed to tighten up the pipes and close the leak.

Replacing glow plugs in the Jeep Libertys 2.8-liter diesel engine is similar to changing spark plugs except there is no firing order to worry about. The glow plugs thread into the cylinder head just below the intake manifold on your Liberty and have a single wire connected to the top, providing seven volts of electricity to the plug. The plug heats up the cylinders on your diesel engine to allow faster start-ups when the engine is cold.

Instructions

1

Open the hood of your Liberty and locate the negative battery cable on the top of the battery. The battery sits on the drivers side of the engine compartment, right behind the drivers-side headlight assembly. Loosen the clamp bolt on the cable end with a wrench and remove the cable from the battery, isolating it from the terminals while you are working.

2

Locate the glow plug in question on the side of the cylinder head. The cylinder head is at the top of the engine assembly, running front to back along the engine block. Grasp the wire at the top of the glow plug at the boot and pull it straight off the plug. Lay the wire aside.

3

Place a socket over the glow plug, attach a ratchet, and turn the plug counterclockwise. Pull the plug out of the cylinder and discard it.

4

Caully insert the new glow plug in the cylinder head. Tighten the glow plug to 110 inch-pounds with a torque wrench. Snap the wiring harness connector onto the top of the glow plug. Repeat the process for the remaining glow plugs until you have replaced all that are defective.

5

Install the negative battery cable on the negative battery terminal. Tighten the clamp bolt with a wrench, making sure it is secure. Do not over-tighten it or you may damage the cable end or terminal. Close the hood of your Jeep.

Replacing the fuel/water separator on the 2.8-liter diesel engine in your Jeep Liberty is not something that you need to do regularly, but when the time comes, a new separator assembly is available from the Jeep dealer. The fuel/water separator is important, as it works to remove moisture and sediment from the diesel fuel before it enters the fuel rails and engine. Water can damage the engine and cause it to run poorly or not at all.

Instructions

1

Disconnect the negative cable from the battery, using a wrench to remove the retaining bolt. Isolate the negative cable from the battery while you work.

2

Locate the fuel/water separator on the firewall of your Liberty. It is to the left of the engine, directly in front of the driver. Locate the two electrical connections on the front of the separator. Depress the locking tab on the connectors and remove them from the separator body. Lay the wiring connections aside.

3

Remove the hose clamp on the large fuel line at the front of the separator using a flat-head screwdriver. Pull the hose off the fitting and push it aside. Locate the second fuel line on the passengers side of the separator. Remove the hose clamp from the line with a flat-head screwdriver and pull it off the fitting.

4

Remove the two bolts that secure the separator to the firewall of the Jeep, using a socket and ratchet. Pull the assembly off the firewall. Position the new separator on the firewall and install the retaining bolts. Tighten the bolts to 63 in.-lbs. with a torque wrench.

5

Connect both fuel lines to the fittings on the new separator. Attach the hose clamps and tighten them with a flat-head screwdriver. Do not overtighten them or you will damage the rubber hose and it will fail prematurely.

6

Attach the wiring harness connectors to the front of the assembly. They are different so you cannot plug them in wrong. Push the connectors in until they snap into place.

7

Reconnect the negative cable to the battery. Reattach the retaining bolt and tighten it with a wrench.

A faulty drain cock or petcock on a 2007 Jeep Liberty could result in a radiator leak, an overheated engine and costly repairs. The petcock is a small valve located on the lower left side of the radiator. The petcock threads into the face of the radiator tank and replacing it is a fairly simple task that requires few tools. Make sure to drain the radiator before you remove the petcock to avoid spilling coolant.

Instructions

1

Open the hood of your Jeep and remove the radiator cap from the radiator. Set the cap aside then slide a jack under the front axle and raise the Jeep off the ground. Place a set of jack stands under the Jeep to support it.

2

Slide a section of rubber tubing onto the drain cock and place a drain pan below it. Open the drain cock with a wrench and allow the coolant to drain from the system. Spin the drain cock out of the radiator with a wrench and thread the new on in place, tightening it with the wrench. Make sure the drain is closed.

3

Raise the front of the Jeep off the jack stands then remove the stands from under the truck. Remove the drain pan from under the truck and lower the truck to the ground.

4

Fill the radiator with coolant then place the cap on the radiator. Open the pressure bottle and fill it with coolant until it reaches the full line on the bottle. Start the engine and turn the heat selector to on. Allow the Jeep to run until it reaches normal operating temperature, about five to 10 minutes.

5

Recheck the coolant level in the pressure bottle and add coolant until it reaches the full mark again. Continue checking and filling the bottle until the level no longer falls with the engine running.

6

Recheck the coolant level after several days of normal driving. Add additional coolant as needed at that time.

When the check engine light illuminates on your Jeep Liberty, it is the result of a problem code being sent from a sensor in the vehicle to the internal On-Board Diagnostics (OBD) computer. It means there is an electrical problem. You should have it looked at and fixed by a qualified mechanic before attempting to reset and turn off the light yourself. Once the problem is fixed, it will be very easy for you to manually reset the light and turn it off.

Instructions

1

Find the Diagnostic Link Connector, or DLC, to the right of and underneath the steering column. Plug the scanner into the port and put the key into the ignition. Turn the key to the accessory position.

2

Plug the pocket scanner into the DLC and then turn the ignition key to the accessory position. Turn on the pocket scanner.

3

Select "Erase" on the scanner to turn off the check engine light. You will know it worked when you see "Command Sent" or when the screen on the scanner is back to the main menu.

4

Turn the key to start the engine. The check engine light should now be off. If not, you will need to have the engine looked at again.