Vehicles coming to a repair shop for performance concerns may have problems with the exhaust system, although there is no visible sign of a concern.
In general, a clogged exhaust can be caused by deterioration inside a catalytic converter that causes the internal framework that supports the catalyst to come apart.
Once the framework comes apart, the inside of any exhaust-conveying downstream component, including the muffler, can start to fill with the catalyst material and become restricted.
A clogged exhaust will result in poor performance and an inability of the engine to build rpms in a normal manner.
Quite often an engine will start and idle in a normal manner when the exhaust is restricted. But, once the throttle is opened, the excess back pressure caused by the restriction prevents normal engine operation.
When a restriction in the exhaust system occurs, there is usually a reason.
Engine operating performance or exterior damage to the system can be the cause.
Engine performance concerns that cause a deterioration of the catalytic converter are excessively lean or rich conditions that cause severe overheating of the unit. Be sure to correct the cause and not just the symptom.
Take advantage of comprehensive inspection reports that are available from exhaust system manufacturers.
The inspection is broken down into specific vehicle components which allows the technician to complete a comprehensive vehicle check.
It also provides talking points that can be discussed with a customer to ensure they understand what service has to be performed to correct their vehicle’s exhaust system.
Influence a buying decision with a status report
Finding a system that is nearing failure provides the opportunity for business and, at minimum, gives the customer a ‘heads up’ that may influence their decision as to where the eventual exhaust system repairs will be made.
The general inspection of an exhaust system should include:
Inspect components for deteriorated or broken welds, cracked joints and corrosion damage. Be aware that damage or deterioration in these areas could allow exhaust fumes to enter the passenger compartment.
Inspect the exhaust system for any of the following concerns that could cause poor sound quality or vibration.
Grounding can be a major concern to driver and passenger comfort.
Be aware that alignment of components is critical to proper exhaust system operation. There should be no excess stress or pull on mounting hardware when the exhaust system and vehicle are in their at-rest position. SSGM