- PO305 CHECK COMPRESSION, LOW REMOVE VALVE COVER AND CHECK CAMSHAFT AND SPRINGS FOUND BROKEN SPRING REMOVE AND REPLACE BOTH INTAKE AND EXHAUST VALVE SPRINGS REPLACE FOULED SPARK PLUG. tested compression of engine cylinder 5 was below specs on running compression . removed valave cover on driverside . removed cylinder 5 rocker arms and performed cylinder leakdown more than 11 psi should only leak dwn 1-3 psi the cuse of leak down was the rings ,rings are stuck on pistin causing loss of compression , performed engine carbon clean still has some missfires at idle only has improved needs engine note lifters are making some noise as well.
GEORGE W. gave our service a 5 star review on 5/26/2022