matts6887

also; one other thing; in attempting to do at least the front ones myself; should at least one of the battery terminals be removed to reduce the risk of shock? or is there no need to do this?

matts6887

Anyone? Battery Cable need to be taken off?

Lexuswiz

iTrader: (1)

It is always good habit to remove the battery when working on anything electronic, but I myself and a few techs I know do not. It's only absolutely necessary if you're touching anything related to the airbags and SRS system.

mylexbaby

in theory, no, yet for your own safety, and given your relatively limited experience, it wouldn't hurt to disconnect the positive cable (just know how to reset everything after reconnecting the battery)

you didn't say how many miles are on them or whether this is the first time the plugs have ever been changed, but time and miles can make plugs difficult to remove, and one of the worse things that can happen is to break off a plug while trying to remove it (I speak of actual experience from a few decades ago) -- another is crossthreading a new plug during installation (which experience and a trick* can help prevent)
also, time and miles matter as to whether the coils should be replaced

as for the plugs, buy the original plugs that were installed in the car -- that should save you from having to gap them, and any other plug introduces the chance of a problem

regarding tools, do you have a torque wrench to tighten the new plugs to spec? if not, that might be an added cost, along with the socket you will need, which factors into the question of whether it is worth the difference for you to do the work of the front plugs alone vs having the most reasonably priced shop do all 6 (instead of only the back 3)

and a final suggestion: if the coils are old, replace the back 3 as part of this project AND SAVE THE OLD ONES as possible replacements for the front 3, which you can do yourself if needed

Good Luck!

*the trick is to use a short length of rubber hose that attaches (not too tight) to the top of a new plug and used to start threading the plug in the engine block; if crossthreading starts, the hose will twist/spin off the plug before real damage occurs; if threading is proper, the plug will go in until "hose tight", then you can pull off the hose and finish with the socket and torque wrench

matts6887

miles wise I have a bit over 135000 on the current plugs and coil packs. So I’m wondering if I’m on borrowed time as far as that goes? I’ve seen some posts elsewhere where someone had gotten to 150000 miles without changing them and I think they may have been the original plugs. It’s not the front im wondering about it’s the dreaded rear ones that I’m trying to decide on whether or not to try and tackle myself. My problem is that I don’t have a spare vehicle to use if my rx were to be out of service for a day if I had to go elsewhere during the day.

mylexbaby

if you've "never really done work on any car", you are picking a relatively hard job to take on; and your reliance on this car running means more downside for the risk you would take on
and you should expect to find plugs and coils after 135K to be more challenging due to time and age (if they aren't, you would be lucky)

last, there's a reasonable chance that a plug or coil going bad will give you some warning (engine misfire or a CEL)

05ls430518

iTrader: (1)

Use ngk plugs anything else will make your car run like *** also pay a shop to do it there is plastic and aluminum that needs to be handled if you are not good with cars the chances of you over tightening something and braking it is very high.

AST300

Unless I was a very experienced auto tech, or a masochist, I would not change the plugs myself but would take the car to the dealer. I believe the Lexus engines are mounted sideways (aka east-west) in most models, making access to the rear bank of plugs very difficult on V6 engines.

lexsc4

My wife 08 RX350's plugs were replaced at 133K miles and they were almost done, according to my mechanic. As for coils, I chose to replaced the rear 3 coils while I already paid the labor charge. I probably don't need to replace them, but if any one of those rear coils goes bad, I have to pay the labor again. I was able to source 3 Toyota coils from ebay (reputable sellers) at $60 each. Anyway, I spent $180 extra for that peace of mind.

mylexbaby

the plugs should be expected as worn (or even well worn) at that mileage -- yet as an informal test, did the gas mileage change after the replacement?

and as I noted in an earlier comment in this thread, maybe you had your mechanic return those 3 old coils from the back to you -- they can come in handy for replacing a front coil if one (or more) as needed

lexsc4

Yep, the plugs were well worned at 133K miles, he gave them back to me. The gas mileage did inprove a little, but not signficant since my wife drives short trips (picking up kids, run errans). I do notice the car idles/drive a little smoother than before.

Yep, my mechanic did returned those 3 old back coils to me. He told me to keep them in case any one of those front three fails, it is really easy to replace.

matts6887

well in this case i somehow need to get the money to get it done. I did find one place locally that would do it for like I think they said 325 for front and rear plugs. That’s the lowest I’ve found so far. And yes I’m just holding my breath waiting for the cel to come on and one or more coil packs burning out

lexsc4

I would jump on it at $325. I paid $500 labor charge and I supply all parts. I am in the SF bay area so labor cost is a little higher here.

matts6887

Well I’ve decided to try and tackle it myself as both a good friend of mine that use to be a auto tech thinks I should be able to handle it myself and so does my sisters husband who is also a big car guru and does work on both of their vehicles himself and use to work for a auto shop

lexsc4

Sound like a good experience. Beer/pizza and half a day with the boys.
Best of luck and do report back after the job completion.