2000 Lexus rx300 misfire problem

[Ray Commons]

The issue I'm having is when I reach speed of about 50 mph. My car starts to shake bad until I take my foot off the gas. It shakes back to front not side to side. I first replaced the mass air flow sensor but had the same problem. I had someone tell me the number 2 coil was bad so I changed it. Still have a problem. I changed the plugs. Still have a problem. I was told my problem was in bank 1. The 2-4-6 cylinders. I'm now gonna change the vvt - the vertical valve timeing cylinoid. Is there something else it could be?  Has anyone had the same problem. 

[Filehorse]

Based on your description it's impossible to make any kind of diagnosis with any certainty.  However, it appears that at this point you are just throwing parts and money at the problem.  I think it's time to find a good independent Toyota/Lexus shop that will have the proper diagnostic equipment to give you an informed determination of what the problem is. It'll cost a lot less than coil packs and valve timing solenoids.  Good luck.

[Ray Commons]

2000 rx300. Where is the oil control valve screen (filter) or does one even exist on this engine

[Lexus_DK]

First of all, is the check engine light on? Any codes? Is the Abs/Trac or the VSC lights on? I agree with Filehorse. Have the dealership diagnose your vehicle. Most shops usually charge a 1 hour diagnostic fee between $120-160 to run a Health Check. They can provide a live data and pinpoint which cylinder or cylinders are actually misfiring or whether you have any failing sensors.

[Ray Commons]

The dealer is far from my house so I took it to a local shop. 5 different codes came up. P0125-coolant temp. P0330-knock sensor. 2circuit bank 1.  P1130. A/F sensor. (Bank 1 sensor 1). P1150. A/F sensor. ( bank 2 sensor 1). P0171. System too lean (bank 1). I hope I'll just have to change the 2 A/F sensors. Will that that fix the P0171 code as well?  The knock sensor is labor intense. I hope it's not that. I'm not sure about the P0125. The car seems to b running at normal temp conditions. Thanks for your advise.