low compression or zero engine compression

[@jim2611]

Hi, excellent explanation - the best I've seen so far. I have a Corolla 2ZR-FE engine. Cylinder 1 & 2 compression is OK. But Cylinders 3 & 4 both have low compression - about half of C1 & 2. I did compression again with oil in the cylinders but that didn't bring compression up so it doesn't look like piston rings are the cause. There is no oil or coolant leak or mixing. Unlikely to be a valve problem as that usually affects only one cylinder? So the low compression is most likely caused by a leak in the head gasket between C3 & 4? A leak down test would tell more but I don't have the instrument or a compressor. What do you think? cheers, James, Sydney, Australia 🙂

[@DRDROP-fj4bo]

I have a 2011 Kia 2.4 GDI. Only at idle after warm up engine shudders. It runs perfect besides that. No vacuum leaks,new coils,plugs,injectors,maf, HP fuel pump. I have cleaned carbon off intake vales. Compression is 150 all 4 cylinders . Book says 170 min. I guess I have one of these problems? Good video Thank You.

[@hanynowsky]

Exhaust valves seats full of carbon. You need a walnut blast after taking off the exhaust manifold.

[@johndana1792]

Where are you located?

[@DRDROP-fj4bo]

Texas compression 150 all cylinders

[@nextdoorpowerwashing8340]

put new timing chains and valves because I only had no compression on the #3 cylinder. put back together after lapping all valves new gaskets and still no compression on the #3 cylinder. I have pulled it back apart to see if I missed anything. The leak test on cylinders is good except for # 3 compression test good on all but number #3....... Im lost don't know what to check next for no compression. car never ran hot. did valves because I thought they made contact... car doesn't smoke