2009 Jeep Wrangler with engine coolant leaking from the engine. A visual inspection of the engine found a coolant leak at the lower intake manifold gasket and lower radiator hose at the water pump. Our Jeep technician replaced the intake manifold gaskets and lower radiator hose. They also warned of a possible water pump gasket leak that should be monitored.
Problem
The customer reported a slow but steady coolant loss and an orange fluid puddle on their driveway under the engine.
Diagnosis
Our Jeep technician did a visual coolant leak inspection from the engine compartment and below the engine from under the vehicle. They found signs of coolant leaking from the front corner of the lower intake manifold gasket running down the timing cover at the front of the engine and a coolant leak from the lower radiator hose at the water pump.
The technician also warned of a possible water pump and timing cover leak due to dried coolant stains on both. Both the water pump and timing cover are made from aluminum and can corrode, develop pinholes in the metal, and leak if the engine coolant is not flushed and replaced as recommended by the factory maintenance schedule.
We recommended replacing the intake manifold gasket, replacing the lower radiator hose, and degreasing and cleaning the coolant-stained area at the water pump and timing cover housing so that they can be monitored and inspected for possible coolant leaks.
We provided a detailed inspection report with photos, explained our technician's diagnosis, and provided a comprehensive repair cost estimate. The customer approved our repair proposal, and we went to work. The job was completed the same day, and the customer was delighted to have their vehicle returned quickly.
Cause
Jeep intake manifold gasket failure due to age and use. Over time, repeated exposure to high engine heat causes the gasket to expand, contract, crack, and leak.
Jeep V-6 engines are prone to intake manifold gasket leaks. The intake manifold gaskets are made from thin steel. They are prone to corrosion and failure if the engine coolant is not flushed and replaced at the manufacturer's recommended service interval. The coolant's anti-corrosion additives lose their effectiveness, and acids in the coolant increase and corrode engine parts and gaskets.
Repair
Remove & Replace Intake Manifold Gasket
Our Jeep technician drained the engine coolant and removed the necessary components to access and remove the engine intake manifold and thermostat. We always recommend replacing the engine thermostat on a vehicle of this age if there is no record of it being replaced.
Next, the technician inspected the manifold for corrosion, cracks, or other signs of leakage. They removed the old gaskets from the manifold and cylinder heads and then cleaned and prepared the surfaces for the new gaskets. Next, they installed new intake manifold gaskets and a new thermostat and reassembled the intake manifold and components removed during the repair.
For this repair, we used a new after-market engine intake manifold gasket set, a new engine coolant thermostat, a new engine coolant, and a new fuel injection throttle body mounting gasket.
Remove & Replace Lower Radiator Hose
Next, the technician removed the lower radiator hose from the vehicle, cleaned and inspected the hose connections on the radiator and water pump, installed the new hose, and secured both ends with hose clamps.
They then cleaned the coolant leak residue from the water pump and timing chain housing and added new engine coolant to the proper level.
Oil & Filter Change
As a precaution, the vehicle was given an oil and filter change. When the intake manifold is removed, coolant will leak into the oil pan and contaminate the engine oil. The vehicle was due for an oil change, so it was given our Premium Engine Oil Service, which includes 5W20 Synthetic Blend Oil Change, a premium oil filter, a friction fighter oil additive, and a digital vehicle inspection report, including checking lights, under-hood fluid levels, and tire pressure.
Best Practice
An engine oil change is required whenever the intake manifold is removed on a V-6 engine. Removing the intake manifold without some coolant spilling into the oil pan is impossible, and the contaminated engine oil must be drained and changed after the intake gasket replacement is completed. Engine coolant-contaminated engine oil will damage the engine bearings and quickly damage the engine.
The engine started and was run until it reached normal operating temperature, ensuring all air was purged from the cooling system. A road test and final coolant leak inspection confirmed the intake manifold coolant leak was solved.
The vehicle owner was advised to regularly check the coolant level and report any signs of coolant leaks. They were also cautioned that the vehicle may require additional leak testing and repairs if there are water pump or timing chain housing leaks.
A cooling system flush and new coolant installed. The new coolant will help prevent further cooling system corrosion and damage. Jeep is one vehicle for which bi-annual engine coolant replacement is highly recommended and will prevent expensive cooling system repairs as the vehicle ages.
Jeep Wrangler Intake Manifold Gasket Replacement Cost
How much does it cost to replace a Jeep Wrangler Intake Manifold Gasket?
How much does a Jeep Wrangler Intake Manifold Gasket Replacement cost?
The national average cost for a Jeep Wrangler Intake Manifold Gasket Replacement is between $590 and $675, depending on the engine and vehicle model.
The national average cost for a Jeep Wrangler Radiator Hose Replacement is between $286 and $310, depending on the engine and vehicle model. The price is lower if the hose is replaced at the same time as the intake manifold gaskets.
The price will vary depending on the repair shop's location within the country, vehicle year, make, model, options, and the quality of the replacement parts. You should contact a local auto repair shop for a more accurate estimate based on your location and particular vehicle.
Diagnosis of the problem, related repairs required to complete the repair, shop supplies, environmental and disposal fees, and taxes are not included.
Tips
Engine coolant should be replaced every two years. Poor engine coolant maintenance can cause premature intake gasket failure.
Coolant leaks due to intake manifold gasket failure are very common for this Jeep model. We replace the original gaskets with higher-quality aftermarket gaskets and follow the factory replacement instructions. There have been many reports of new gasket failures if the repair procedure is not done exactly as specified by the vehicle manufacturer.
Coolant leaks should be repaired as soon as possible. Vehicle coolant is poisonous to humans and pets. Pets are attracted to its sweet smell and will eat it, which can kill them. Children can also be attracted to the engine coolant's bright color and sweet smell. Ingestion of coolant will cause severe internal organ damage.
Coolant leaks also cause severe environmental damage when coolant enters waterways, groundwater, and storm drains.
FAQ
Can an intake manifold gasket coolant leak cause overheating?
The low engine coolant level will cause engine overheating.
What are the symptoms of an intake manifold coolant leak?
There are three main symptoms of a leaking intake manifold gasket:
- The coolant reservoir level decreases over time. This can be an indication of a slow or rapid leak.
The leaking coolant fluid puddles where the vehicle is parked. This indicates a serious leak that should be inspected and repaired as soon as possible. If the leak is ignored until the engine overheats, severe damage can be caused. - White smoke flows from the exhaust pipe, and the engine can misfire. This is a serious problem where the coolant is drawn into the engine's combustion chamber. If ignored, this problem can affect engine performance and cause severe engine damage, leaving an easily noticeable stain.
- External coolant leaks usually leave a trail where the hot coolant travels and dries, leaving a visible stain easily noticed by a visual coolant leak inspection. Coolant typically leaks at the front or rear corners where the intake manifold meets the cylinder heads and runs down the front or rear of the engine. Leaks are usually easily visible and, when they get large enough, will leave puddles under the vehicle when parked.
Less commonly, intake manifold gaskets leak coolant internally, either into the crankcase, where the coolant mixes with the engine oil and turns the oil to a thick milky sludge, or into the intake port and eventually the combustion chamber, where it creates steam or white smoke from the exhaust pipe. This is a serious problem in either situation that should be repaired immediately.
Your dashboard will often display a check engine warning light when you have a coolant leak. Typically, this will be a low coolant level warning; in the worst case, it will be an engine overheat warning, which is a serious problem.
An auto repair technician should check a coolant leak immediately.