My car makes the ticking noise when it WARMS UP - NOT when it is cold. The timing chain was changed because they were taking the engine apart to replace the water pump, there is 54,000 miles on the car, and we thought we would change the chain now as preventive work since it is recommended to be done at 60,000 miles. It purred like a kitten before this. Now they are telling me it is "scored rod bearings" not a loose timing chain. We put in a heavier, synthetic oil, but still the noise. Wouldn't the noise get worse as the engine is reved if it was the rod bearings? And wouldn't it make the noise even when the engine was cold if it was the rod bearings? Help!
Ticking noise in engine on 2002 Chrysler Sebring
The 2.7L engine is a very expensive engine to overhaul. Good diagnostics as opposed to guess work is essential here. The viscosity of the oil is thicker when cold, especially in the north east. A Rod knock is a fairly heavy knock as opposed to a tappet noise which is a higher frequency "ticking" In the case of a lightly worn bearing, the rod knock would usually heard when the engine is under a load and may not be heard when the engine is idling. If the bearing is severely worn, a knock would be present at all times, louder when under a load. Carbon build up on the top of the pistons will cause a knock. Decarbonizing the engine with MOPAR COMBUSTION CHAMBER CONDITIONER, used as directed will help if carbon build up is in fact the cause. If ANY of the crankshaft or rod bearings are failing, the use of a "heavier" multi-viscosity oil will not help . Put the vehicle in gear, HOLD THE BRAKE ON, and raise the engine RPM. Under this load, a rod bearing will be consistant at all engine speeds.
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