Hello, if you've got cylinders misfiring like that, it can cause the catalytic converter to melt down unless your vehicle has cylinder deactivation. But if you're putting the pedal to the floor and it's just not making any power, yes the converter could be the problem. You can try a couple things, either unbolt the front of the converter and see if you regain power, it will be loud but you'll know if the catalytic converters the issue, or pull the upstream 02 sensor and it should have about the same effect. Releasing some of that pressure. Regarding the timing belt break, you may want to have a cylinder leakage test done. That's a very small engine and if you're missing 2 out of the 4 cylinders, that's a huge amount of power loss. Here's a couple articles with a little insight. If your fuel injectors are accessible you can try unplugging each injector one by one and do a type of cylinder balance test, see how each cylinder reacts to it's injector being unplugged and write down the results. It's a quick power balance test. Checking fuel pressure should be done too, losing fuel volume at higher RPMs is possible. One last quick test is, hold the gas pedal to the floor in park, this should activate clear flood mode, crank the engine without starting it and listen to see if it's cranking over smooth, no variation in the sound, you can usually hear a cylinder if it has low compression this way. It's called cranking cadence.
Thursday, June 24th, 2021 AT 12:44 PM