P1456 – Check engine minor EVAP Leak.. Not the Gas cap

ANSWER : Hi there. When the fuel cap is not securely fastened to the tank, it can create vacuum issues inside the tank; which triggers the error code to be stored in the ECU. The error will then trigger the check engine light until that code is reset by a professional digital scanner. If you’re still having sputtering or stalling issues, you should contact a professional mechanic to complete an engine sputtering inspection. This will allow them to diagnose what’s causing this problem and reset any error codes to hopefully correct the issue your Chrysler 300 is experiencing.

ANSWER : If you smell gas, there can be a leak in a number of places. All the fuel lines should be carefully inspected to make sure they are secure and undamaged, all the way up to the fuel injectors themselves. Even a minor fuel leak can allow fuel to evaporate, making is seem ;like you are getting poor mileage. While it should be inspected along with all the fuel lines, if you especially smell gas inside the car, the fuel pump-to-fuel tank seal should be inspected as well. The fuel pump can be accessed under the rear seat bottom. Once it is removed, there is a triangular-shaped panel in the middle of the floor. The wiring harness grommet must be removed first, then the 3 screws can be removed to access the fuel pump, located on top of the fuel tank. The fuel line connections and tank seal should be inspected and/or replaced if needed. Other causes can be a leaking or damaged purge valve or canister, as well as hoses connected to them.

The best course of action would be to have a certified technician check the system for fuel leaks before randomly replacing parts. That can get expensive as most fuel and electronic-related parts are not returnable once purchased and/or installed.

ANSWER : It is possible the tank was filled too much, that is the gas pump did not shut down when it should. Even if gasoline was not filled right to the top, thermal expansion can later cause the gas to overflow if the tank gets warmer and pressure builds. The too high level will subside quickly as all you have to do is drive 25 miles or so to lose a gallon. If you believe there is a leak or other issue, a certified Mechanic from YourMechanic can perform a leak inspection during a mobile visit.

ANSWER : What you are describing sounds like a dirty or faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

ANSWER : Hi there. The system will set the message if it attempts a self test and finds atmospheric pressure in the tank. The gas cap may not be the concern here as this message is directly related to a large leak in the system. This system extends from the filler neck, to the tank, to the engine, and the canister. Obviously, I would not think that a new canister is not failing, but it has happened before. A smoke test on the evaporative emission system will reveal any open leak in the system. There could also be solenoid malfunctions, loose wiring connections, or broken wires. Any of these can set codes, but the "tighten gas cap" message is simply a self check to make sure you have tightened the gas cap and not an actual diagnosis of the system. So many people have left gas caps loose and end up in the service drive over the check engine light; how would you feel if you were charged the door rate to have your gas cap tightened? I know the answer and I agree, I wouldn’t be happy about that either. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

ANSWER : Hi there. It’s quite possible that this is a rear oil seal or oil pan gasket that is leaking; or perhaps a transmission oil tube seal that is leaking. The problem with trying to diagnose an oil leak is that typically the oil tends to spray onto different components underneath the vehicle. You might want to have a professional mechanic complete an oil leak inspection to help you locate the source of the leak and recommend the right repairs.

ANSWER : If it was leaking "antifreeze" or "coolant" on the freeway, that signifies a cooling system leak although it is also possible that your car is overheating (due to a cooling system problem like a stuck thermostat or an engine issue) and the overheating simply caused the pressure relief valve in the radiator cap to open expelling steam and liquid coolant. It’s hard to say which is occurring without looking at the car directly. Consider YourMechanic, as one of our mobile technicians can come to your home to diagnose the Check Engine Light and other symptoms.

The fault with the battery is possibly a coincidence and the electrical issue will have to be dealt with as well. It’s not unusual for older cars to have multiple problems but the problems are not directly related; they are merely coincidental.

ANSWER : Hello there, thank you for asking about your 1992 Isuzu Pickup. A professional will have the correct equipment to read OBD1 codes. Retrieving the diagnostic trouble code(s) is the first place to start when diagnosing your vehicle. Increasing RPMs changes engine load, which can in turn affect many different sensors and components, causing the Check Engine Light to illuminate. The only way to narrow down the options and find the culprit is through in person diagnosis with an OEM compatible scan tool. A certified technician from YourMechanic can retrieve the OBD codes at your home or office.