Hello all, I am new here but I have researched this site before purchasing a '99 RX300 AWD in Aug '07.
Recently, my fiance' had noticed a rough idle and intermittent stumbling at highway speeds. 2 days later the CEL came on and the symptoms had returned. After much research on this site, I thought I had it narrowed down to spark plugs, a bad coil pack, or an O2/air/fuel sensor. I retreived the codes at a local parts store and purchased new plugs and 1 coil pack to get started figuring I would use the extra coil pack to help diagnosis. However when I got home and looked up the codes, I noticed that there were multiple misfires on all cylinders on the same bank and I have a VVC issue. I then thought it was maybe just an air/fuel sensor causing the mayhem and contemplated swapping the 2 pre-cat sensors to see if new codes would reflect the opposite bank. After a bit more research, I see that the P1349 code may be a precurser to a more serious issue.
Would something as simple as a bad coil pack or bad sensor cause misfires in the entire bank? I am hoping it is something simple that I can do myself at minimal cost. Unfortunately, the problem occurs in the bank near the firewall which is a PITA. I understand new sensors are around $200 and that dealers suck your bank account dry so I want to get a better idea of what I am dealing with before I go down that avenue and would appreciate any suggestions or insight.
Details:
1999 RX300 AWD
IAC recently replaced (July 07)
154K miles
P0300
P0301
P0303
P0305
P1349
Thanks in advance for any feedback!
Eric