It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy ...

If the filter checks out OK, a faulty sensor, a clogged fuel injector, or another intake-system component may be to blame. Because of the vast complexity of modern fuel-injected engines ...

Tip submitter Robert Krickus asks, "Would adding a solvent as demonstrated alleviate the clogged injector problem of biodiesel? I'm assuming there is a difference in sensitivity to the quality ...