Got a ES300 with 100k+ miles on it. Customer said he had done tune up 6-7months ago. Now his emission date is coming next month, got 10 codes possibly stored ones and when the incident(misfire happened maybe)

Codes as follows:
P0300
302
304
306
P0171
P0325
P0330
P1354
P0302
P0171

I know 300 is random misfire and 302,304,306 is cylinder misfire, also 325 and 330 are the knock sensor codes. Can it be possible that the misfire may have caused the knock sensor codes? I won't get the car in my hand till tomm thought i'd freshen up a little early. Also is it coilon plugs? Thanks for your time in reading this thread.

 

Wow, that's a lot of codes. I, too, have as ES300 (2000) with just over 100,000 miles. I, too, had the CEL come on. It happened at the exact same time as I felt a cylinder or two missing. The engine ran rough, but I made it home and checked the codes and, sure enough, the codes were 300, 305, and 306. it turned out that I had two bad coils that needed to be replaced.

http://www.troublecodes.net/Lexus/ or for a good diagnisis: http://www.obd-codes.com/

 

yea that's what I'm thinking i'll have to switch the coils around see what happens then and i'll also have to inspect the coils. Someone told him that he needs to do a tuneup and replace knock sensor but I have a feeling it's a bad coil. hmm. I have cleared the codes so when he brings it in tomm I will see what stored codes there are.

 

Was the timing belt changed recently? Sounds like the cam timing is off; especially since cyl 2 4 and 6 are on the same bank or the original belt skipped a tooth if it wasnt done.

 

The knock sensor codes indicate that there is a problem with the wiring to the sensor, or the sensor itself. Miss-fires will not generate the knock sensor codes. Also before chasing the mis-fires, look into the VVT code first. Most of your misfires are on bank 2, which is the back that is generating the VVT error. Having bank 2 valve timing off is what is probably generating the misfires.

 

I would clear the codes, and start reading fresh codes as they show up.

 

wow, those codes bring back so much memories, had em all a few months back, now just down to one code p0171 for running lean, what i did was change my cat, knock sensors, 02's, coils, n plugs, now it runs so much better, couldnt even go over 40mph before