Hello all. I am not a Mechanic but I have no choice to fix this myself and with your help as well. I was quoted 2000 to fix this. I really hope you can help me
Vehicle: 2009 Cadillac CTS 3.6l 77000 miles.
Issue started at a stoplight out of nowhere. Idle going crazy barley alive. Misfire like hell. got it home asap.
Bought a code reader and got P0300 codes (multiple cylinder misfire) Went through normal steps of checking vacuum leaks and found none. Changed all plugs and coils - no fix. problem is deeper.
I now rented a compression tester from autozone.
Cylinder 5 = 128 PSI ------ Cylinder 6 = 0 PSI
Cylinder 3 = 130 PSI ------ Cylinder 4 = 145 PSI
Cylinder 1 = 132 PSI ------ Cylinder 2 = 145 PSI
So no Compression on cylinder 6.
I have found a broken valve spring in the back where cylinder 6 is. Before I go further I need professional advice from you guys so I don’t really mess things up. I can rent or buy the tools needed. I did try and loosen the bolts on the cams but they will not budge!!! I can take more Pictures - please help me get back on the road.