Okay here is my problem. My car is misfiring really bad, I hooked it to the computer and it shows all cylinders misfiring. I took it to my local foreign mechanic and his computer details same thing. He told me the timing chain guides are broke and need to be replaced because he hears a rattle when the engine is running (coil packs,spark plugs have all been replaced). He told me that it would cost around 2.5K to do the job but if the valves are bent I need to replace the whole engine. Is this true? Is fixing the bent valves that expensive that I would be better off replacing the whole engine? Considering the engine would already be pulled to replace the timing chain guides.

 

If you have bent valves, the heads will have to come off. Replacing the valves can be done instead of throwing a whole new engine at it. This can be done with the engine in the car. Still labor is going to be about the same. A "new" engine will be way more expensive than fixing the one in the car. A quick compression check on all the cylinders will tell you if you have bent valve or not. Pull the plugs, install the pressure gauge in the hole, spin her over. Any cylinder with 0 PSI has a bent valve. Compression should be at least 120-130 PSI or more on each cylinder.