Engine Code P0171 A Step-by-Step Guide to Troubleshooting

The engine seems to be running really rich (can smell a lot of gas at startup). I've checked for exhaust leaks, did my best to check for a vacuum leak, and ... When the code says that the fuel system is "too lean," it means that the computer has been adding more and more fuel, which is called Long Term Fuel Trim. More often than not P0100, P0110 and P0171 are related to the MAF being dirty or worst case damaged. Normally you start with the lower codes ... The most common cause that we see at the dealer is a MAF sensor, especially if you have a K&N or other oiled air filter. O2 sensors can also ... the same lean code on both banks indicates it is a fault that affects the whole engine, so less likely to be an O2 sensor. I would take another ... P0171 indicates that the oxygen sensor in bank 1 has detected a lean condition (the engine either receives too little fuel or too much air). P0171 and 174 are related to the injectors on Banks 1 & 2 reporting a lean condition, meaning they aren't supplying enough fuel. A faulty MAF ... It is a code related air/fuel mixture that the engine is creating. To lean means that there is too much air compared to the amount of fuel being ... The check engine code was P0171, a lean fuel trim. He cleared the code and checked for air leaks and said the car needed a new PCV valve and he installed one. I was able to get enough gas to get to a decent gas station to fill the tank. On my way home I got a check engine light and the code was P0171( ...