Hello all,

2012 Versa Sedan SV is throwing a P0300. Have checked for air/vacuum leaks. Have changed the spark plugs and gapped correctly. Have replaced the coil boots as I was having spark leak. Also have spark knock/rattle. Mechanic told me that when he hooked up his computer the car is running lean all the time. He cleaned the MAF and the Throttle Body.

Help diagnosing is appreciated.

Thank you.

Case closed. The culprit was the ground from the block to the radiator support faulting. Took it off, sanded the paint off of the support, grounded the grime off of the contacts and bolted it back on. Runs fine.

Was told by mechanic to check fuel pressure next, got sprayed in the face with fuel when I didn't have the tester hooked up right, then did the relief procedure again. Saw the ground arcing when the engine was starting. Finally figured it out, several months and several hundred dollars later....thank god