rapaulino29 0 Posted March 27 Report Share Posted March 27 Hello Forum Members, I am a new member and I need help with my wife RX-300 2002. The car has 251K miles and It is starting to fail on her. The engine light came on and the scanner read the following codes: P0300 - Multiple Cylinders Misfired Bank 1, Bank 3, Bank 5, and Bank 6 How serious is this? I understand that working on bank 1, 3, and 5 is very difficult. Help! Thanks in advance, Raphael Quote Link to post Share on other sites
Filehorse 6 Posted March 28 Report Share Posted March 28 If all these codes appeared at the same time it would seem they have a common cause such as a bad connection in the coil harness or the fuel injection harness. Ignition coils are a common problem with this generation RX but they would fail individually. Fuel pressure is another common source that would cause multiple misfires simultaneously. Here is a link which discusses the P0300 code for your Lexus and that might help. https://www.autocodes.com/p0300_lexus.html#disq I also would not discount the camshaft position sensors or the crankshaft position sensors as they can also create havoc with the engine control system. Given the age of the vehicle and the mileage you should think carefully before throwing a lot of money at the vehicle in search of the cause and then the repair. Good luck. 2 Quote Link to post Share on other sites
Lexus Owners Club 11 Posted 23 hours ago Report Share Posted 23 hours ago On 3/28/2021 at 12:31 PM, Filehorse said: If all these codes appeared at the same time it would seem they have a common cause such as a bad connection in the coil harness or the fuel injection harness. Ignition coils are a common problem with this generation RX but they would fail individually. I agree, more than likely some corrosion in the connections to cause all of the cylinders to go down at the same time Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.