IoT

I got this car at 34k miles and never replaced its Spark Plugs or Ignition Coils.
With 159k miles, I am thinking. should replace these.

1) What do you all recommend?
2) What brand of Spark Plug and Ignition Coils I should use? OEM or any other brand?


Thanks
Lexus ES350 2010
159K Miles

luxuryrice

At that mileage a spark plug change would make sense, but if your car isn't throwing any ignition coil codes, i'd keep the old ones. New ignition coils get pretty expensive , so if you dont have to replace them , I wouldn't.
I just did my spark plugs on my '07 ES and I used Denso Iridium Twin Tip ( https://www.rockauto.com/en/moreinfo...t=7212&jsn=356 )
Denso is what Toyota uses from the factory, my car has a noticeably smoother idle and acceleration after replacing them.

spaceballs

I would always go with OEM (Denso in this case), as spark plugs in the ES are iridium so you would replace them maybe twice in the full life of the car.
No use in saving a few pennies going with aftermarket only to do it again, especially as the rear bank is a pain to get to.

If your coils have no problems, don't replace them, but if you want to do it and save a bit of money I would replace the rear bank only, then save the removed coils for when the ones on the front bank fails, and when those fail also, replace the front bank ones with new. Denso make very good quality coils so if one breaks, you only need to replace that one, and not all the other ones on the same bank.

IoT

The engine-check light on Lexus ES350 2010 (153k miles) came on a few times and after I turned off the car and started it again, the check engine light went off.
Diagnostic Codes are:

• P0300- Random/ Multiple Cylinder Misfire Detected
• C1201- Brake Boost Sensor Circuit Range/ Performance

Neither Spark Plugs nor Ignition Coils were ever changed,

Today, I changed the front 3 Spark Plugs only but the above codes persist. I go it diagnosed it from 2 different local auto stores,

1) Should I change the rear 3 spark plugs first and see if the codes go away? or change the front 3 coils first?

2) The front is very easy but accessing the rear spark plugs and ignition coils is different.
I saw this video Is there any better video or approach to accessing the rear ones?

3) Is there any way to test if coils are working, outside the engine, using a multimeter, etc?

PS
The local mechanic was asking $800 for changing all 6 ignition coils and spark plugs (Denso parts and labor). Is that a fair price?
Labor is $300, rest is for parts.