Disclosed herein are embodiments of method for detecting degradation of a connecting rod big end bearing within an internal combustion engine including a crankshaft and an exhaust manifold included on a vehicle. A method includes providing an electronic control unit connected with the engine, a first set of sensors for detecting crankshaft acceleration connected located adjacent the crankshaft, a second set of sensors for detecting engine exhaust manifold pressure located adjacent the engine exhaust manifold, and a display component and an auditory component connected with the electronic control unit. The display component and/or the auditory component is activated when the first set of sensors detects diminished crankshaft acceleration during a power stroke compared to prior acceleration of the crankshaft during a power stroke and the second set of sensors detects exhaust manifold pressure that does not vary statistically significantly from expected exhaust manifold pressure.

Methods and systems are provided for a heat exchanger phase change material installed as a component of a variable exhaust tuning system. In one example, a method may include absorbing excess heat energy from exhaust gases during and after an engine-on event within a heat exchanger material, releasing heat energy stored in the heat exchanger material during and after an engine-off event, and heating an adjustable exhaust valve with the heat energy stored in the heat exchanger material.

A urea solution spray nozzle maybe provided that can suppress the deposit and growth of urea in the urea solution spray nozzle. A urea solution spray nozzle according to at least one present embodiment is such that urea solution flow paths and gas flow paths and are constituted, and urea solution and gas are mixed and injected from an injection port, and a slit, which is a lateral ejection port, is constituted in such a manner that the gas is ejected in the same direction as the injection direction of the urea solution along surfaces of the urea solution spray nozzle, and a water-repellent coating layer is formed on the surfaces of the urea solution spray nozzle.

Methods and systems are provided for differentiating an exhaust air leak from a catalyst monitor sensor degraded with a slow-response. In one example, a pressure proximate an exhaust system particulate filter less than a threshold pressure may indicate an exhaust air leak and responsive to the indication of the exhaust air leak, the thresholds for monitoring the catalyst monitor sensor response may be adjusted. In this way, the impact of an exhaust air leak on catalyst monitor output may be accounted for so that subsequent monitoring for threshold catalyst may continue to be performed accurately in the presence of an exhaust air leak.

Disclosed is an exhaust gas aftertreatment system (1) for a diesel engine, the exhaust gas aftertreatment system comprising: a treatment agent tank (2) for storing an exhaust gas treatment agent; a metering injection module (4), with the injection of the metering injection module (4) being controlled with a determined duty ratio signal according to a desired injection amount; a supply module (3) connected between the treatment agent tank (2) and the metering injection module (4) for supplying the exhaust gas treatment agent to the metering injection module (4); an exhaust gas treatment agent pipe (6) connected between the metering injection module (4) and the supply module (3); a pressure sensor for measuring the system pressure in the exhaust gas treatment agent pipe (6); and a controller (7); wherein the controller (7) is configured to receive a system pressure signal from the pressure sensor during injection of the metering injection module (4), and detect an injection abnormality of the metering injection module (4) based on at least a first amount, which represents an actual injection amount and is determined by the system pressure signal, and a second amount, which represents a theoretical injection amount and is determined by a corresponding duty ratio signal. A corresponding injection abnormality detection method is further disclosed. The injection abnormality detection method is simple and reliable.

Methods and systems are provided for a heat exchanger phase change material installed as a component of a variable exhaust tuning system. In one example, a method may include absorbing excess heat energy from exhaust gases during and after an engine-on event within a heat exchanger material, releasing heat energy stored in the heat exchanger material during and after an engine-off event, and heating an adjustable exhaust valve with the heat energy stored in the heat exchanger material.

An exhaust gas control apparatus for the internal combustion engine includes a catalyst disposed in an exhaust passage, an upstream air-fuel ratio sensor configured to detect an air-fuel ratio of in-flow exhaust gas that flows into the catalyst, a downstream air-fuel ratio sensor configured to detect an air-fuel ratio of out-flow exhaust gas that flows out of the catalyst, and an electronic control unit configured to control the air-fuel ratio of the in-flow exhaust gas. The electronic control unit is configured to, when a predetermined condition is satisfied, control the air-fuel ratio of the in-flow exhaust gas based on an output from the downstream air-fuel ratio sensor without using an output from the upstream air-fuel ratio sensor. The electronic control unit is configured to, when the predetermined condition is not satisfied, control the air-fuel ratio of the in-flow exhaust gas based on the output from the upstream air-fuel ratio sensor.

A method for producing a shrink-fitted member by arranging a hollow type pillar shaped ceramic body inside a metal pipe and shrink-fitting them, the hollow type pillar shaped ceramic body including: an outer peripheral surface and an inner peripheral surface in a direction substantially parallel to an axial direction; and a first end face and a second end face in a direction substantially perpendicular to the axial direction. The method includes arranging the hollow type pillar shaped ceramic body inside the metal pipe while gripping the hollow type pillar shaped ceramic body using a chuck mechanism.

Methods and systems are provided for a heat exchanger phase change material installed as a component of a variable exhaust tuning system. In one example, a method may include absorbing excess heat energy from exhaust gases during and after an engine-on event within a heat exchanger material, releasing heat energy stored in the heat exchanger material during and after an engine-off event, and heating an adjustable exhaust valve with the heat energy stored in the heat exchanger material.

Methods and systems are provided for adjusting and troubleshooting an adjustable exhaust valve of a variable exhaust tuning system. In one example, a method may include comparing engine startup conditions to engine conditions of a last engine off event, adjusting a position of the adjustable exhaust valve, and providing a diagnostic summary to a vehicle operator based upon the results of the comparison and adjustment.