2002 honda accord v6..has a p1399 code also po302, po304, po300..

Question

when dtc's are erased an cleared, code p1399 first to pop up almost instantly after e clearing codes..i drained coolant and ran car without the coolant in system and car runs lil smoother and check engine light doesnt come back on instantly, i let run for 10-15 mins reving engine then finally put in drive after awhile code shows up.what is the problem im having?..there is a sputter coming out the exhaust also.

Answer 1

Hi there,

These are all misfire codes. If the car is using coolant, then you may have a head gasket leak. This could also be a timing belt issue. Since it idles rough, you can also check for vacuum leaks. With the engine running spray some carb cleaner along the intake manifold and see if the idle smooths out or increases. If it does, then you have a vacuum leak.