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.
The reasons your urine has a strong odor include: -Foods, medications and vitamins can all potentially cause your urine to smell. For example, eating asparagus or pineapple can both change your urine's odor in different ways. -Dehydration can leave the urine more concentrated, so it takes on more of an ammonia-like smell. -Bacteria in the urine can give it a foul odor. This can be caused by a bladder infection or fistula (when an opening forms between the bladder and bowel). -What causes urine to smell sweet? This may be due to high blood sugar, and can be a sign of poorly controlled diabetes.