Coil cylinder numbers on 2000 ES300?

Cecil · June 26, 2016

Hi, I was trying to help a friend. She was being charged $250-300 a pop to replace ignition coils on her 2000 Lexus ES300. She wants to replace the remaining ones now before they fail on her. Her receipts show cylinders #1,3,4, and 5 were replace individually over the past few years and all 6 spark plugs were replaced about 20k miles ago. I was expecting to replace the #2 and #6 coils, and from an online diagram I determined those should be the front left and front right cylinders (i.e front right and front left of engine compartment).

After looking at the coils installed on her car 3 of them were stamped denso on top of the coils and looked newer, one was only stamped with made in japan and a model number, and two were stamped Toyota Denso and were dirty and looked older. The problem is the older looking coils were located in the front middle cylinder (of engine compartment) and the rear left cylinder (rear left in engine compartment along firewall) which appears to correspond to cylinders 4 and 1 from the firing order diagram.

I am concerned I may have replaced the wrong coils. :( Are the original coils stamped Toyota on them? Do mechanics number the cylinders another way other than the 1-3-5 firewall bank left to right and 2-4-6 front bank left to right? The only way I can come up with a way to say I replaced 2 and 6 would be to count 1-2-3 on the front bank in either direction and then 4-5-6 on the rear bank going right to left.

Thank you.

gbhrps · June 27, 2016

Cecil,

Toyota (Lexus) numbers their V6 engine cylinders thusly:

Pasenger side firewall #1, middle firewall #3, Driver side firewall #5

Passenger side grill #2, middle grill #4, Driver side grill #6

As for the original coil markings, I suspect they would look older and would be marked Denso (too many years and several cars since I had an ES300).

Cecil · June 27, 2016

Thank you. I don't know what the mechanic did before me but he definitely replaced coils other than what was on the receipts. I looked on ebay for used original coils and found this pic. This coil looks identical to the 2 coils I replaced, I assume this is what the original coils look like...