Originally Posted by nhdoc

There was another person exhibiting similar symptoms that turned out to be the pre-filter o-ring had not been installed correctly...certainly that is a very cheap fix, so why not try that first and see if it helps. Since it is sold separately from the filter many times it does not get replaced, but it should be!

Also, others have reported trouble with the K40 relay...more costly than the o-ring but not a wallet buster either...search under K40 to find other posts about it.

Good luck.