Hi Everone great site.!I have an 1987 ford f150 4.9 140,000 miles. To keep it running i have to bring up the rpm's. I replaced the fuel filter, added fuel injection cleaner and water remover. Spark plugs,wires,dist. cap, rotor and air filter where changed a few years ago. Throdle body and injectors where cleaned two years ago only put a 1000 miles since. Never changed the O2 sensor. I read that a O2 sensor needs to warm up to 600 deg before it will run bad ??? With the fuel reg. was told to pull vacuum hose out and smell for gas, which means a bad reg?? Cant get the volt meter to move when checking codes, started to move then nothing. No engine check light on 87's. Thanks