mine did the same it turned out to be the injector
No compression could mean a blown head gasket, cracked head or cylinder.
Check the Piston Ring.
WHEN INSTALING THE DISTRIBUTOR THE ROTARY BUTTON HAS TO BE POINTING AT THE NUMBER 1 CYLINDER AT TDC
Remove number one spark plug and squirt some motor oil into the cylinder. Now do another compression test. If the compression goes up considerably in number one cylinder you probably have bad/worn or cracked piston rings. If the compression doesn't change much you probably have burned or bent valves.
Remove the spark plug for each cylinder and screw a compression tester in it's place. Crank the engine around a few times and record the highest number achieved.
Number one cylinder is located driver's side front of engine. With the # 1 piston at TDC on the compression stroke, the rotor will be pointing at #1 plug on cap.Number one cylinder is located driver's side front of engine. With the # 1 piston at TDC on the compression stroke, the rotor will be pointing at #1 plug on cap.
check the compression
check your compression on #4 cyl
Run a compression test on #2 cylinder. You either have a burnt valve or cracked head.
sounds like your engine needs a valve job worn piston rings would also cause low compression ,but not cause the backfireing
Yes
That would be the top of the compression stroke on the number one cylinder.