Toyota 4Runner Problem Reports

Newest Toyota 4Runner Problem Reports

Report A Problem

A loss of power on the freeway may due to an internally leaking fuel pulsation dampener. This commonly occurs on higher mileage vehicles.

The timing chain can develop a rattling noise caused by failing timing chain guides. This is often due to extended mileage intervals between oil changes that allows the oil to become dirty and abrasive which wears away the timing chain guides until they fail. The timing chain and guides should be inspected at each valve adjustment, otherwise serious engine damage may result.

The 3.0 V6 engine is usually prone to leaks in the head gasket after as little as 60,000 miles. When the head gasket is replaced, the knock sensor harness should be replaced as well, as it can be damaged by leaky head gaskets, resulting in a serious decrease in fuel efficiency or in long term engine damage.

Typically the AC compressor is worn out by about 150,000 miles in warm and/or humid climates. It is recommended to replace the complete compressor including a new clutch and rpm sensor, and to replace the receiver/dryer as well.

Usually by 150,000 miles the AC system will need some attention, especially in climates where it is used often. Our technicians tell us that it is best to service the AC system every 2-3 years. This keeps the moisture in the system at a minimum which extends the life of the components.

The AC Expansion Valve may develop a very slow leak or allow too much refrigerant flow which reduces cooling. Our technicians tell us that Toyota makes an updated expansion valve to resolve these problems if and when they occur.

A rough idle and even an emissions inspection failure for high HC and CO can be caused by improperly adjusted valves. Also, exhaust valves may become to tight which can lead to valve failures. Our technicians tell us that regular valve adjustment inspections are a must.

Over the time the exhaust gas recirculation (EGR) system may become plugged with debris, the oxygen sensor may also be getting slow or 'lazy' around this time. When servicing or cleaning  the EGR system, it is a good idea to replace the oxygen sensor because it works in tandem with the EGR system.

At 125,000-150,000 miles, the Master Cylinder may need replacing. It is critical to adjust the brake pedal to Master Cylinder pushrod clearance or the brakes will drag and over heat.

At 125,000-150,000 miles, the Master Cylinder may need replacing. It is critical to adjust the brake pedal to Master Cylinder pushrod clearance or the brakes will drag and over heat.

Front brake rotors can wear causing a pulsation felt in the brake pedal. Our technicians tell us this condition is best corrected by replacement of the front rotors and brake pads.

If the engine will not crank over, the most common problem is the starter. These will tend to go out at about 100,00-125,000 miles. Sometimes it is only the starter solenoid, but often the complete starter (including solenoid) needs to be replaced.

At higher mileages (125,000 -150,000) the power steering pump may begin to leak on the 6 cylinder vehicles and could require replacement.

At higher mileages, (125,000-150,000) the automatic transmission may not shift correctly. This can be caused by the throttle position sensor being out of adjustment or a shift solenoid needing to be replaced. Typically the transmission does not need to be completely overhauled.

The Throttle Position Sensor can get out of adjustment due to wear in the throttle body or due to carbon build up. This will cause the idle timing to advance more than 30 degrees which will cause very high HC and NOx emissions. Conversely, the Throttle Position Sensors can wear out and not properly advance the timing which causes a lack of power and poor fuel economy.