When the car engine P1191 Code is found, you need to check the list first. The check list is Fuel Rail/System Pressure – Too High, Engine Shutoff Solenoid Malfunction and Crankshaft Position Sensor A Circuit Low Input. You also check all symptoms of the car engine problem to know the real cause of the car engine problem. Here, the powertrain is the problem or faulty. When you block your car with gas, the gases in the tank get enforced into a canister engaged with triggered charcoal. Also, on a hot day as the gas heats up and evaporates, those same gases push into the container where they are stored.