There are no lines next to the spark plugs. "Chips and Networks" dont often set such convenient codes. There are a couple of common air leaks. There is a hose that connects to the aluminum part your intake manifold directly in front of your oil filter. Other times the canister purge valve- the one that ticks real loud when driving located behind the left headlight- can stick open or close and act as an air leak. A third is a little tricky. There is a line that runs to the pressure modulator on the right side of the transmission, the modulator itself can leak-the car may shift fine but still be getting unmetered air. good luck