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.

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 the key cylinder on the steering column of your Jeep Wrangler may be necessary if damage has occurred to the tumblers or pins inside the cylinder. A replacement cylinder is available from the Jeep dealer and can be keyed to use your existing key for a fee. The cylinder can be swapped quickly and does not require a bunch of specials tools to complete.

Instructions

1

Sit in the drivers seat of your Jeep and insert the ignition key into the cylinder. Locate the hole in the bottom panel of the steering column directly below the cylinder.

2

Insert a small screwdriver or punch into the hole in the column and push the pin inside the hole up. Turn the key and cylinder to the "On" position then pull the cylinder straight out of the column. Remove the screwdriver or punch from the hole under the column.

3

Turn the key to the "Off" position then withdraw the key from the cylinder. Insert the key into the new cylinder and turn the key to the "On "position on the new cylinder.

4

Insert the cylinder and key into the column the rotate the key to the "OFF" position. Withdraw the key from the cylinder.

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.

Removing the shifters from the floor of your Jeep Grand Cherokee for replacement or to access another part of the Jeep requires the removal of the center console. The bolts that secure the shifters are under the console and you cannot get to them with the console in place. The shifters are both mounted in on a bracket so they must be removed as a single unit and replacing one means replacing both. Replacement shifter assemblies are available from the Jeep dealerships parts department or you may find a used assembly from a salvage yard in like new condition, saving you money.

Instructions

1

Sit in the drivers seat of your Jeep and set the parking brake. Insert the ignition key into the ignition and turn the key just far enough to unlock the transmission. Depress the brake pedal and shift the transmission all the way to the rear then turn the key back to lock.

2

Lift the rubber mat out of the front bin in the console, exposing the retaining screws under it. Remove the screws with a Phillips screwdriver and set them aside.

3

Open the armrest on the console and locate the two screws in the base of the compartment. Remove the two screws with a Phillips screwdriver and set them aside. Slide the rear cup holders out to allow you to access the two screws under the rear of the console.

4

Remove the rear retaining screws with a Phillips screwdriver. Lift the console up and over the shifters then set it aside.

5

Locate the two cables coming to the front of the transmission and transfer case shifts and pry the retaining clips up and off the bracket with a small pry bar. Using a screwdriver, pop the shift cable off the side of the shifter on both sides then lay the cables aside.

6

Remove the four retaining bolts that secure the shifters and bracket to the floor of the Jeep with a socket and ratchet. Lift the entire assembly straight off the mounting studs and remove it from the Jeep.

The oxygen sensor on your 1996 Jeep Cherokee helps regulate the fuel consumption and emissions. The sensor is threaded into the exhaust manifold and monitors the oxygen saturation in the trucks exhaust. The Cherokees computer adjusts the fuel-and-air mixture combusted in the engine based on the oxygen saturation. If your truck begins to burn a noticeably greater amount of fuel compared to its normal fuel consumption, buy a replacement oxygen sensor from an auto parts store and change it at home.

Instructions

1

Lift the front of the Cherokee with a jack until it sits high enough to fit jack stands underneath it for support. Place the jack stands under the frame rails just behind the front wheels. Lower the Cherokee so that it rests securely on the jack stands.

2

Disconnect the electrical connection from the oxygen sensor. Remove the sensor with a wrench or oxygen sensor socket attached to a ratchet.

3

Spread a thin layer of anti-seize compound on the threads of the new sensor. Do not get anti-seize compound on the sensor head. Thread it into place by hand. Tighten the sensor with a wrench or a socket and ratchet.

4

Connect the wiring harness connection by pressing it together until it clicks. Lift the truck with the jack until you can remove the jack stands. Return the truck to the ground.

Replacing the flasher in your Jeep Cherokee may be necessary if the turn signals or the emergency flashers stop working. The flasher controls both operations, and if it fails it usually stops working completely. Replacement flashers are readily available from any auto parts store or Jeep dealer. The flasher is buried behind the fuse panel, so it will take a little time to reach but the whole job shouldnt take more than about an hour for most experienced DIY mechanics.

Instructions

1

Open the drivers door of your Jeep and locate the access panel for the fuse box on the end of the dash. Remove the fuse box access panel by unsnapping it from the right cowl side trim panel.

2

Remove the nut securing the right cowl side trim to the junction block stud with a socket and ratchet. The nut is near the center of the fuse block.

3

Remove the two screws along the edge of the right cowl side trim to the right of the fuse box using a Phillips screwdriver. Set the screws aside.

4

Pull the trim panel off and locate the flasher inside the junction block. Unplug the combination flasher from the junction block.

5

Push the new flasher into the block. Position the trim panel back in place. Install the retaining screws along the right side of the fuse box and tighten them with a screwdriver.

6

Install the nut in the center of the fuse block. Tighten it with a socket and ratchet. Snap the access cover onto the fuse panel. Close the door of the Jeep.

Removing the glove box from the dashboard of your Jeep Grand Cherokee may be necessary if you are working on something behind the dashboard or if the glove box has damage to it that requires replacement of the entire assembly. You will not need any tools to remove the glove box, and the entire process takes just a few minutes to complete. Replacement components and assemblies are available from the parts department at any Jeep dealer.

Instructions

1

Open the glove box until the stops on the back edge are resting against the rubber stop bumpers in the upper glove box opening. Reach into the glove box and, with the middle finger of each hand, push the rubber flap on the two glove box stop bumpers toward the front of the vehicle.

2

Roll the glove box door down until the stops on the back edge of the glove box pass through the openings in the upper glove box opening. Grasp both ends of the glove box door, then twist and pull the door as necessary to disengage the inboard hinge hook from the inboard hinge pin on the dashboard.

3

Raise the glove box door until it is perpendicular to the instrument panel then twist the door slightly counterclockwise and shake the door slightly to disengage the remaining two hinge hooks from the instrument panel.

4

Pull the glove box straight out of the dashboard. Set it aside in a safe place so you can reinstall it later if you will be reusing it.

Removing the gas tank from your 1989 Jeep Wrangler and replacing it with an aftermarket or original equipment (OE) replacement will only take a couple of hours and basic hand tools. Before you start, be sure the gas tank is empty (or as close to it as possible) to reduce the weight of the tank and the possibility of a spill. The tank sits between the frame rails under the rear of the Jeep, all the way to the rear of the frame.

Instructions

1

Position a jack under the rear of the Jeep and raise the vehicle off of the ground. Place a set of jack stands under the rear axle housing and lower the jack, allowing the Jeep to rest on the stands.

2

Locate the two nuts on the j-bolts at the front of the gas tank. Loosen the nuts with a wrench, allowing the tank to sag on the mounts. Reach between the tank and the body of the vehicle and remove the hose clamp from the filler hose on the top of the tank.

3

Disconnect the wiring harness connectors from the terminals on top of the tank and set them aside. Position a floor jack under the center of the tank to support it, and then remove the nuts from the j-bolts.

4

Slowly lower the jack and tank away from the frame of the truck. Remove the steel support straps from under the tank, and then slide the tank out from under the rear of the Jeep.

Removing the vacuum shifter from your Jeep requires access to the front axle housing from under the Jeep. The vacuum shifter, used in the early Cherokee and Wrangler models with a Dana 30 axle assembly, engages when the Jeep is shifted into four-wheel drive. These actuators have long been a problem and a weak link in the system. If yours is not working, removal and replacement or converting the axle to do away with it may be your best option.

Instructions

1

Position a jack under the front of your Jeep and raise it off the ground. Position a set of jack stands under the front axle housing, then lower the Jeep until it is resting securely on the stands.

2

Slide under the passengers side of the Jeep and locate the vacuum shifter or actuator on the axle housing. It sits behind a small metal skid plate or guard. Remove the two bolts from the skid plate with a socket and ratchet, then remove the skid plate and set it aside.

3

Locate the two black vacuum lines on the end of the shifter. Pull the lines off the shifter and lay them aside. The lines are different sizes so there is no concern about mixing them up later.

4

Remove the four 10-mm bolts from the four corners of the actuator or shifter using a socket and ratchet. Set the bolts aside for reuse later.

5

Pry the shifter assembly loose from the axle housing with a stiff putty knife, then lift the assembly off the housing. Scrape any remaining gasket material off the housing and place a clean rag in the opening until you are ready to reassemble it to keep dirt and water out of the axle.

When performing repairs on a 2001 Jeep Wrangler, it is imperative that the correct torque is applied when installing certain bolts. The manufacturer calculates torque specs for the Wrangler based on a combination of bolt strength and the component it is holding. Torque values are verified by the use of a torque wrench that alerts the user of the proper torque through an audible signal, typically a clicking noise.

Lug Nuts

Lug nuts are very commonly just tightened until the nut no longer turns. Most inexperienced mechanics believe that the tighter the lug nut the better, but this is far from the truth. Over-tightening a lug nut stretches the threads of the wheel stud and can lead to breakage once it is heated from driving. This breakage can lead to the other wheel studs breaking due to excessive weight; the resulting domino effect can cause the wheel to fall off. The proper lug nut torque on the 2001 Jeep Wrangler is 110 foot-pounds.

Brakes

When performing brake repairs, each bolt has its own, equally important, torque specification. There are two sets of bolts on the brake system that have specific torque values: caliper bolts and brake hose bolts. The brake caliper bolts require a torque of 18 foot-pounds. The brake hose bolts have a rating of 23 foot-pounds.

Cylinder Head

The cylinder head on the Wranglers engine has a seal that must be torqued to the proper specs in order to seal correctly. The 2.5 liter 4-cylinder engine requires head bolts numbers 1 through 6 and 8 through 10 to have a final torque value of 110 foot-pounds, and bolt number 7 to have 100 foot-pounds of torque (see Resources for bolt numbering). The 4.0 liter engine requires bolt numbers 1 through 10 and 12 through 14 to have a final torque value of 110 foot-pounds and bolt number 11 to have a final value of 100 foot-pounds.

Exhaust Manifold

The exhaust manifold uses a compression-style gasket that requires proper torque to maintain a good seal. Bolt number 1 requires 30 foot-pounds and 2 through 7 require 23 foot-pounds (see Resources for bolt numbering). These values apply to both the 2.5 and 4.0 liter engines.

Oil Pan

The oil pan has two different fasteners, each having their own torque values: 1/4-inch bolts and 5/16-inch bolts. The 1/4-inch bolts require 85 inch-pounds of torque and the 5/16-inch bolts require 11 foot-pounds. These values apply for both the 2.5 and 4.0 liter engines.

Timing Chain Cover

The timing chain cover must be removed when performing timing chain maintenance. This cover has a seal and requires proper torque to obtain a good seal and prevent leaks. The bolts around the timing chain cover require 60 inch-pounds of torque on the 1/4-inch bolts and 192 inch-pounds on the 5/16-inch bolts.

Removing the alternator from the engine of your Jeep will allow you to have the unit tested if you are experience changing-system problems. If you are working on other components on the front of the engine, the alternator may need removing for access to other parts. Whatever the reason for removing it, you can take the alternator off the bracket and out of the engine compartment in about 20 to 30 minutes with basic hands tools.

Instructions

1

Open the hood of your Jeep and locate the negative battery cable end on the negative battery terminal. Remove the retaining bolt from the battery cable end with a wrench, then remove the cable from the battery.

2

Locate the serpentine belt tensioner on the front of the engine and place a socket and breaker bar on the axis bolt, the bolt in the center of the idler pulley, then rotate the tensioner counterclockwise. Remove the belt from the alternator pulley, then rotate the tensioner back to the home position and remove the breaker bar.

3

Locate the electrical connector on the top of the alternator, depress the locking tab and pull it out of the connector on the alternator body. Lay the connector aside for now. Locate the second connector on the rear of the alternator. Remove the retaining nut from the terminal with a socket and ratchet, then remove the wire from the terminal.

4

Remove the upper mounting bolt from the alternator with a socket and ratchet. Set the bolt aside for reuse later.

5

Locate and remove the lower mounting bolt from the alternator with a socket and ratchet, then lift the alternator off the mounting bracket and out of the engine compartment.

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.

Replacing the hub assembly on the front of your Jeep Cherokee is the only way to service the front wheel bearings. Because the hub assembly is a sealed unit, you cannot repair it without special tools. Replacement units for the Jeep front axles are readily available through most auto parts stores and of course the Jeep dealer network, however. The job can become time consuming, but in the end doing the work yourself can save you a substantial amount of money.

Instructions

1

Locate the hub nut and cotter pin in the center of the front wheel on the side on which you will be working. Remove the cotter pin from the shaft with a pair of needle-nose pliers, then discard it. Place a large socket (generally 36 to 45 mm) on the axle nut, and use a breaker bar to rotate the nut counterclockwise until it loosens.

2

Loosen the lug nuts with a lug wrench, then place a jack under the front of the Jeep. Raise it off the ground, and place a set of jack stands under the front axle to support the Jeep. Remove the wheels, and set them aside for now.

3

Locate the two brake caliper retaining bolts on the top of the brake caliper. Remove the two retaining pins with a socket, then ratchet the lift the caliper off the brake rotor. Support the caliper from the top of the suspension with twine to keep it from hanging on the brake hose.

4

Slide the brake rotor off the hub, and set it aside. Locate the three 12-point bolts on the backside of the steering knuckle that retain the hub to the steering knuckle. Remove all three bolts with a 12-point socket and a ratchet. Set the bolts aside.

5

Remove the axle nut from the axle shaft, and pull the hub out of the steering knuckle and off the axle. If it has rusted to the steering knuckle, use a cold chisel and hammer to work around the edge of the hub, separating it a little at a time. It will come out with enough persistence.

6

Clean the interior surface of the steering knuckle with some break clearer and a clean rag then coat it with some anti seize compound. Slide a new hub over the axle shaft and into the steering knuckle. Install the three 12-point retaining bolts from the back of the knuckle and into the hub. Tighten the bolts, drawing the hub completely into the knuckle.

7

Slide the rotor onto the new hub and wheel studs, then position the brake caliper on the rotor. Install the retaining pins into the caliper, and tighten them with a socket and ratchet.

8

Install the axle unit onto the axle shaft, and tighten it until snug. Torque the three 12-point bolts to 75 foot-lbs. with a torque wrench. Install the tire on the hub, and tighten the lug nuts until snug.

9

Raise the front of the Jeep off the jack stands, then remove the stands from under the axle. Lower the jack, setting the Jeep on the ground, and tighten the lug nuts the rest of the way with a lug wrench.

10

Tighten the axle nut to 175 foot-lbs. with a torque wrench, and install a new cotter pin in the end of the axle shaft, bending the legs over with a pair of pliers to hold it in place.