Problem Reports

The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops.  There is also a revised vacuum check valve available to address this concern.

Some vehicles may exhibit one or more of the following: Spark knock complaints when the vehicle is under load, various single cylinder misfire, and surge in 4th gear (around 45 mph). Our technicians tell us that rerouting the coil and spark plug wires to minimize induction effects will commonly correct this condition. If wires must cross during the reroute procedure, they must cross at a 90 degree angle.

Leak detection pump failure can be caused by the internal diaphragm switch sticking, or in some cases, contamination from debris or carbon particles from vapor canister. If black carbon particles are present in the LDP, replace vapor canister in addition to LDP. The purge solenoid should also be checked for debris or carbon contamination and replaced as necessary. All evap system hoses are subject to cracking and splitting causing leaks, Inspect hoses carefully. In cases of contamination from carbon particles or debris, all hoses and tubes must be blown out with compressed air to remove contaminates.

On vehicles equipped with a Theft Security system a loss of power to the Central Timer Module can result in a no start condition.

The Central Timer Module may stop working intermittently causing various body systems to also stop working. There is a revised CTM available to that should correct this condition.

Some automatic transmissions may set a code P1740, torque converter fault. Our technicians tell us there is a revised transmission pressure boost valve cover plate to correct this condition.