The role of the charge air cooler (CAC) in a diesel or turbocharged engine is crucial for both performance and efficiency. The CAC cools down the intake air that enters the cylinders, which allows for higher boost levels, more power, and lower exhaust gas temperatures. However, these benefits rely on properly functioning CAC hoses connecting the CAC to the intake manifold and turbocharger.
What is a Charge Air Cooler?
The charge air cooler is a heat exchanger installed in the intake tract of a turbocharged or supercharged engine. Hot compressed air leaving the turbocharger enters one side of the CAC, where it is then cooled by circulating coolant from the engine. The charge air cooler hoses carry this now-cooled intake air to the intake manifold, and ultimately into the engine’s cylinders.
By cooling down the intake air charge, the CAC allows for higher turbocharger boost levels while preventing excessive temperatures that could damage vital engine components. Without a charge air cooler, exceeding certain boost levels would generate dangerously high intake air temperatures that could cause pre-ignition, detonation, and poor combustion.
Why Are Charge Air Cooler Hoses Important?
The charge air cooler hoses are essential for the CAC system to function as designed. The first hose carries hot, compressed intake air from the turbocharger to the charge air cooler, while the second hose transfers the now-cooled intake air from the CAC to the intake manifold.
If either of these hoses leak, break, or become disconnected, the CAC will not be able to properly cool down the intake air charge. As a result, excessive intake temperatures could cause permanent engine damage within just a few seconds. Additionally, leaking or blown charge air cooler hoses may trigger engine fault codes and illuminate warning lights on the dashboard.
Signs of Worn Charge Air Cooler Hoses
There are a few indicators that your CAC hoses may need to be replaced:
- Loss of power – Worn hoses prevent the CAC from optimally cooling the intake charge, which limits boost and power output.
- Engine fault codes – The engine computer will often detect issues related to faulty CAC hoses and set appropriate diagnostic trouble codes.
- ABS, traction control, and check engine lights – These warning lights may come on as a result of CAC hose problems.
- Intense turbocharger or intake manifold vibrations – These components can shake violently if a hose becomes disconnected.
- Intense intake manifold or intercooler heat – CAC hoses that leak or break will allow hot, uncompressed air to enter the intake tract.
- Rubber degradation – Over time, the rubber in the hoses will dry out, crack, and become brittle. This is an indication they need to be replaced.
How Often Should Charge Air Cooler Hoses Be Replaced?
Most experts recommend changing out the charge air cooler hoses anytime between 60,000 and 100,000 miles as a standard preventative maintenance procedure. Though rubber CAC hoses may hold up beyond 100,000 miles, they become increasingly prone to failure the older they get. As the rubber breaks down, it becomes harder and harder for the charge air cooler to properly cool down your engine’s intake air.
Overall, replacing worn CAC hoses every 60,000 to 100,000 miles ensures the charge air cooler system is functioning at its optimal performance level. Newer hoses made from synthetic rubber compounds may last even longer than traditional rubber charge air cooler hoses.