iginoc

Recently I had a misadventure with my 11-years old RX450h and had to replace the tailgate lock and motor actuator... I had to bite the bullet, as there was no alternative; my trusted bodywork shop spent a whole day on it before throwing in the towel, too much electronics in this car he said.

Anyway while I was at the dealer signing the 2000 $ check for the tailgate job, I asked the employee to go through the maintenance records to see if everything was all right there (I am the third owner of the car which has been in my possession for six years).

Now, according to the maintenance records it looks like my car spark plugs are still the factory ones, strange enough nobody at Lexus noticed it.. after the drain on my wallet due to the tailgate failure, I was thinking to sell the car since here it does still have a decent residual value, despite the age (11 years) and the mileage( around 173000 km or 109000 miles)

However, since in this conjuncture I am not in position to buy a brand new equivalent vehicle, and the RX is the only car in which I can easily seat my 101 years old mother, probably I will keep the RX but... I was wondering, if at this point I really need to replace the spark plugs as advised by the Lexus employee (he said that with such old spark plugs, the engine light can come up at any moment).

But he said also that replacing the plugs is the most expensive routine maintenance of the list, around 1000 $ of cost... by other hand, I have no mechanic skills, and I need my vehicles to be reliable. Any thoughts?

RadiantX45

I feel like spark plugs shouldn’t cost that much. Maybe call a Toyota shop and see what they charge that’s always my first go to.

Seattle SCone

$1000! Holy..... Oh, I see https://www.clublexus.com/forums/rx-...ug-change.html
They are a bit more fiddly to access the plugs than some other Lexus. Still, $1000 seems a bit steep.
The issue with aging plugs is they will appear to be running find until the load of their increasing spark gap kills an associated coil.

Wow, I feel lucky with my SC430 - All 8 plugs doable under an hour as a DIY.

iginoc

1000 $ (800-900 Euro) is the presumable cost of the 180000 km periodic maintenance check which comprehends not only the cost of 6 iridium spark plugs but also the labor and other items foreseen by the maintenance schedule, such as lubricant and filters replacement, and various inspections.

Undoubtably is quite expensive, and since appear likely that even this year due to the pandemic I will put just 2-3000 more miles in the car, I am prone to let her go with the current plugs, and delay the replacement to next year,

Droid13

If it makes you feel any better, I have also been very lazy when it comes to changing spark plugs. My RX450h is coming up on 12yrs this summer, has 230,000km and still running on the original plugs. I also have an 18 yr old Sienna with the 3.3L V6 with 300,000km still running perfectly fine on the original plugs. At this point I feel trying to change the plugs is likely to cause more problems than just leaving it, so that van will go to the scrap yard with original plugs when the time comes I think.

paperthin

No kidding. I was lazy also and had our changed out around the 230k km mark. We are at 270 now.

salimshah

When it comes to recommended maintenance item, the only input I take is from the manufacturer as listed in the set of owner manuals. The decision (risk) is totally mine. The iridium plugs last a long time and I have not looked at 450H recommendation about them as my ODO is far from 100k miles.

The only personal experience I have is that on first gen I gambled and did not replace them at 110K miles. At around 126K miles, I got misfire on 1 plug and sure enough the plug was bad, as confirmed by swapping. Shortly (within 1K miles) the coil pack on the previously bad plug gave way. It could have been a coincidence or the bad plug stressed the coil.

At the end it is unto the owner to choose to follow, postpone, or preemptively do the service items. For the procrastinators, I would caution that the part may fail at the most inopportune time. To me, personally it does not make sense to postpone the items which would be one or twice in the lifetime of the vehicle. [On the other hand can can save a service trip by extending the interval ... oil change every 11K miles ... you will do 9 instead of 10 services] . The parts and labor will not be cheaper in a month or two or 6.

Whenever cost of service is discussed, please ask the shop to give you parts and labor costs separately. Since I mostly do DIY, I am out of touch with labor costs. As long as consumers keep paying it, the service provider will keep jacking the rates up.

Salim

STVDave

When ever you mention 'dealer' your talking big bucks. They charge more for the parts and more for the labor. A regular garage can put in a cheaper part and work for a lower hourly charge.
BUT. I saw a you tube on changing these plugs. You have to dismantle everything above the engine. I find this a deplorable engineering job that requires you to remove the windshield wiper mechanisms along with the other crap around them. Plus various intake pieces. This just to get to the other side of the engines plugs.

iginoc

As I seid before, I have not mechanical skills, so replacing the sparks it is definitively a task out of my reach.

However according to the ubiquitous Murphy Law issues happen when boundary conditions are the worst possible. In fact,I consider myself lucky for the tailgate didn't break on a Sunday with my mother aboard, because I didn not have to crawl over a folded weelchair to unlock the tailgate.... besides, Salim note about the potential influence of the plugs on the coils struck me.

So I think that should I keep the Lexie (its sale is still an option) I will have the dealer doing the spark job and, with the occasion, the water pump belt too. It's better prevent than fight...

iginoc

I paid a visit to the Lexus' dealer which kindly offered me a 30% discount on the new spark plugs, so at the end I had the work done, together with water pump belt replacement (it was still the original one) and periodic check comprehending lubricant and filters replacement, as well discounted

NickSP

I'm surprised you don't have an independent Hybrid repair shop near you. When I purchased my 10 RXh, I took it to the shop servicing my Prius and they knew this car inside out. I bought the spark plugs and the transmission fluid from Lexus and simply paid labor for changing the spark plugs and draining the fluid. Both at a very low cost than what the dealer wanted. Anyway glad you got it done.

iginoc

BTW since I had the spark plugs job done I am experimenting my best fuel consumption ever, 14,5 km/l (34 MPG) while in this period of the year I was typically in the range of 12 km/l (28 MPG).
I wonder if there is a relationship between new spark plugs and fuel economy...

NickSP

wow. 34mpgs? How do you manage to get that much? What's your commute like?

iginoc

Well I drove a Prius for 12 years... ; keep also in mind that here where I live the driving environment is quite different in respect to yours, I can tell because I have driven in the US several times, the most recent last March in DFW, Texas.
Anyway my current setup is the following
1) low resistance tyres (18" Continental summer tyres)
2) avoid as much as possible prolonged acceleration and abrupt braking, the contrary is better (brisk acceleration up to the target speed, and anticipated/prolonged coasting/regenerative braking)
3) moderate use of air conditioning (A/C is a battery SOC killer, low SOC is likely to start forced battery recharging which is a fuel economy killer per se). Lukily my RX has the sunroof...
4) energy monitoring with Scangauge II (actually I have two Scangauges connected in daisy chain). Monitoring the SOC and current flow is essential in order to prevent battery depleting and consequent ICE driven recharging.

NickSP

I have a Prius too but I didn't think getting 34 on a RXh was possible. Good for you.