Spark Plugs - 2015 Lexus RX350 167k miles

[Hillbilly Deluxe]

You really don't need a dedicated space. If you have a reasonably organized basic toolbox, a table for organizing items and a 3/8" drive impact wrench/driver, the job can be executed by any reasonably competent DIYer. A lot of these jobs are not that difficult if you stay focused, even if you do not do them daily. Study the instructions, gain an understanding of how the components are assembled and you will be in a good position to tackle the work. I think you might be underestimating your capabilities.

To answer your question, yes. Spark Plug replacement is a maintenance service by itself. Coil replacement is not part of the service. We cannot reliably predict coil failure; many of them last another plug interval without issues.

I was organized. I did this in my driveway, about 50' from my toolboxes in the garage. I brought out a 6' folding table and put a moving blanket on it to keep stuff from rolling off. I also used the tailgate and bed of my truck to store all the plastic engine covers/etc. I had a 3/8" air ratchet, several multiplies of 10mm, 12mm and 14mm sockets, several extensions, a couple of ratchets, u-joints, flexible joint sockets, etc.

I had a tough time working with the throttle body, getting it separated from the plenum also had a tough time getting the two rear plenum bracket nuts off to remove it. I also had to scrounge and look for my 5mm hex socket, then a bit kit to get that one 5mm cap head that you can't get without a long 5mm hex driver. So I probably spent 15 minutes screwing around with that one cap head screw.

Other than that, I thought I moved pretty darn fast, I was able to scoot through all the bolts with the air ratchet. Still, it took me nearly 90 minutes to be able to get to the rear coils.

 

[Luftmasse]

I was going to say that coils generally don't go bad... It's not like old school rotor and distributor cap.

My coils in my car have 351,000+ miles on them.

I believe bad plugs can cause coils to go bad.

If the vehicle here had 167k mile plugs on it and the vehicle ran good no codes for any cylinder misfires.... Then those plugs actually didn't hurt those coils.

Though I certainly don't knock anyone for changing their coils. Each to their own.

This is not the case on the Honda Accord V6 coils. They go bad.

 

[1uz_4me]

Just flip it upside down....

 

[liberty2701]

My 2017 Lexus rx350 3.5l calls for a 60 k spark plug replacement. The OE plugs are Denso Iridium. I will be going to at least 100 k on the plugs disregarding the interval. I believe the 60k is to meet some emission nonsense

 

[The Critic]

My 2017 Lexus rx350 3.5l calls for a 60 k spark plug replacement. The OE plugs are Denso Iridium. I will be going to at least 100 k on the plugs disregarding the interval. I believe the 60k is to meet some emission nonsense

Plugs are definitely needed every 60k on the newer DI Toyota V6’s. They tend to get very worn by the recommended service interval. These had 62k:

 

[D60]

You’re fast, I don’t think I could do the intake and cowl in a half hour...well I could, but I’d break every connector and vacuum line.And probably lose half my bolts.

And two 10mm sockets if you're me

 

[doublebase]

Plugs are definitely needed every 60k on the newer DI Toyota V6’s. They tend to get very worn by the recommended service interval. These had 62k:

View attachment 82883

Maybe it’s just me but I don’t see anything wrong with those.

 

[The Critic]

Maybe it’s just me but I don’t see anything wrong with those.

Here’s a different picture:

One of them is decently fouled and the gaps were somewhat irregular.

 

[doublebase]

Here’s a different picture:

View attachment 82892
One of them is decently fouled and the gaps were somewhat irregular.

I see it now. That right one.

 

[GSCJR]

Glad mine is not DI, thanks for the cowl removal suggestion @The Critic .

 

[AKhan87]

On the SUV's, removing the cowl actually gives you enough room to remove the rear coils without removing the intake. It isn't fun, but it can be done.

But it only takes 30 mins to remove the cowl and intake on a 2GR. Not worth spending money on coils upfront, IMO.

Agreed, also OEM Denso coils I have had in 10+ plus Toyotas, I have seen 1 fail at 230k miles, other then that, they are more reliable then after market anyday…I have had 500k on OEM Denso coils that worked perfectly….

 

[liberty2701]

Plugs are definitely needed every 60k on the newer DI Toyota V6’s. They tend to get very worn by the recommended service interval. These had 62k:

View attachment 82883

I have the 2gr-fks engine which is a hybrid injection. What injection is in yours?

 

[The Critic]

I have the 2gr-fks engine which is a hybrid injection. What injection is in yours?

Same.

 

[nthach]

I have the 2gr-fks engine which is a hybrid injection. What injection is in yours?

The 2GR-FXS is the “hybrid” version with D4-S, while the 2GR-FSE/FKS is the “regular” D4-S port/direct injected engine.

The main difference is the 2GR-FKS can switch to Atkinson cycle operation for efficiency, the hybrid FXS is entirely Atkinson cycle. FKS also includes an vacuum pump, FXS doesn’t since hybrids have brake by wire.

 

[liberty2701]

The 2GR-FXS is the “hybrid” version with D4-S, while the 2GR-FSE/FKS is the “regular” D4-S port/direct injected engine.

The main difference is the 2GR-FKS can switch to Atkinson cycle operation for efficiency, the hybrid FXS is entirely Atkinson cycle. FKS also includes an vacuum pump, FXS doesn’t since hybrids have brake by wire.

Thank you for the clarification. Seeming you are knowledgeable, how important is the 60 k mile plug change? Seems like Toyota recommends it to ensure emission compliance.

 

[PWMDMD]

Question - if you do this job and don’t replace the three rear coils and one goes out 10k miles later, do you charge the customer for the labor to replace the coils? Do you then replace all three?

Why wouldn't he? Unless there is clearly a problem at the time of spark plug replacement or some manufacture recommendation to replace the coils at a specific interval as part of normal maintenance, I would argue it's gouging to replace something that isn't faulty and isn't recommended to be replaced unless it's faulty. No different than,

"So, I know you're here for new shocks but we should also replace part of the suspension because you know, I already have the wheels off".

"Is there anything wrong with that part?"

"No, but you know it could break soon and it's better to just do this while I'm there."

Maybe a coil goes bad and maybe it doesn't - my crystal ball always seems cloudy. Now for the OP, sure, it's his vehicle and his call but when you go to a professional there's a fine line between prophylactic replacement of parts and unnecessary replacement of parts.

 

[nthach]

Thank you for the clarification. Seeming you are knowledgeable, how important is the 60 k mile plug change? Seems like Toyota recommends it to ensure emission compliance.

As The Critic says, DI is rough on plugs - hence why Denso designed a new tri-ground spark plug for these.

DI can create a stratified charge like Honda’s CVCC/Mitsubishi’s MCA-Jet - a richer mixture near the spark plug and a leaner mixture in the cylinder. More carbon buildup near the spark plug can happen.

 

[Thebigm]

These were over 45k miles overdue according to Toyota / Lexus on this engine. I thought they looked pretty good.

I replaced with the same Denso OEM and replaced the rear 3 coils also with Denso coils (not OEM).

I forgot to order a new PCV valve to do at the same time but it’s easy to get to.

When I changed the factory plugs on my v6 Camry, 3 were Denso and 3 were NGK

 

[Hillbilly Deluxe]

I'll expound a little more on WHY I chose to replace the 3 rear coils on this vehicle:

I bought it used at 162,000 miles. I studied the maintenance history very well before I bought it, through CarFax, Lexus's Owners Site and even called two independent shops the PO (original owner) said she'd had work done at. There was absolutely no sign from anywhere that the plugs had been done at the factory recommended 120k mile mark.

I have heard from a few techs that I respect that excess plug usage/wear can cause coils to fail prematurely. At what point that is, who knows? These are electrical devices. Show me something that has electronic circuitry in it that you will guarantee to be fine for a specified period of time. I'll wait.

This was also my first 2GR-FE plug job. The fear of having to call a tow truck to load my vehicles up when I can't finish a job, screwed something up or whatever is pretty high with me. First, I go into vehicle maintenance/repair in my driveway with the idea that I'm going to save some money. Second, I know if I screw up or something goes wrong, I've got a week-long or more of a headache to go through unraveling it. I've got to find a shop that will take the job over and not beat me up about it when I'm already down and beating on myself, secondly I've got to pay for it, the tow guy and everything else and it won't be cheap.

So I ordered all the parts - plugs, 3 coils, gaskets, etc., so that I was fully prepared to do it all while I was in there. Yes, it cost me an additional $180 to do this job. I spent about $325 in parts - plugs, coils, gaskets. This is a $6-700 job (not including coil replacement) at a shop.

I think I did ok....

I'm good til 300k miles. Well, I need to flush the coolant 3 times and drop the trans pan, replace the filter and gasket and refill one more time and I'll be good til 300k, hopefully.