Defective ignition coil(s) Bad spark plug(s), spark plug wires, or spark plug boots. Faulty fuel injector(s) Malfunctioning fuel delivery system (fuel pump, fuel pump relay, fuel injectors, or fuel filter) Major engine vacuum leak. EGR valve stuck in the wide open position. Clogged EGR ports.
The following conditions can sometimes cause smelly urine, but they are uncommon: 1  urinary stones â these may cause an ammonia-like odour (read about bladder stones and kidney stones) 2  a bladder fistula â this is an abnormal connection between your intestines and bladder.
Benign causes of urine odor. Urine odor may be caused by a variety of conditions that are not harmful or not caused by disease including: Eating certain foods, such as garlic, onions, fish and asparagus. Asparagus can cause a sulfur-like smell of the urine. The unusual odor should go away after these foods have been digested.