Rough Idle, Engine misses thruout, No Powerin drive range.

[alfgar551]

1992 Lexus ES300, V6 Automatic, over 200.000 miles. Engine cleaned and honed out and re-ringed within tolerance. New Gaskets and Heads were checked and had valve job. New plugs, computer changed out, Distributor changed out w/ new rotor/Distributor cap. replaced knock sensors ( code cleared). Transmission fluid and filter changed. Vehicle starts and idles good and afterwards begines to run rough and when you try to drive it , it doesn't have enough power. Former owner states that it use to drive ok and that the vehicle started to smoke (bad head gasket ). The only thing that I haven't changed is the original spark plug wires (?). Any suggestion...This thing is costing me a lot of money....otherwise a real nice car. Help !!!!

[tac]

Do you know if the O2 sensors were replaced? If they're sending faulty readings, that might explain why it changes from smooth to rough after it warms up.

[alfgar551]

TAC Wrote:Do you know if the O2 sensors were replaced? If they're sending faulty readings, that might explain why it changes from smooth to rough after it warms up.

No they were never changed out. I didn't get the code for it.