Celica Forums General Discussion Engine and Performance Cylinders 1 and 3 not firing

Completely Stock 2000 Celica GT 1ZZ Could anyone give me any ideas here. Cylinders 1 and 3 will not fire. I have changed the following: Plugs/coils, Injectors, fuel pump, fuel pressure regulator, fuel Relay, PCV Valve, upstream o2 sensor, Camshaft position sensor, Crankshaft position sensor, also while unrelated really it has new serpentine belt and new air filter. I have ran completely out of ideas. The car will start and run while in park (with misfire), when you shift into gear the misfire gets very noticeable and it has no power. Seemed to have trouble shifting into 4th gear until the engine warmed up before the misfires started happening. Any help would be greatly appreciated. Thanks!

What codes show up?

If it runs OK at idle but misfire and no power under load, there are a number of possible causes. You should trouble shoot it:

1. scan engine for any CEL codes.

2. Inspect the plugs to see how good combustion is at each cylinder.

3. Do compression test.

Looks like you may have a leaky valve seals or head gasket which does not have enough compression in cyl1 and 3 for proper firing. At high speed it may works half way OK, but engine would run rough and waste a lot of fuel. It won't pass any SMOG test.

Problems should be fixedl