ChrisEvo8

I am trying to fix a 2002 ES 300 that was having some misfiring issues. I pulled the plugs close to the front bumper and they looked like they need to be replaced, however no noticeable oil accumulation. However, the three plugs closest to the firewall had a fair amount of oil accumulated in the wells and inside the combustion chamber. Somehow the car wasn't running THAT bad prior it was more at idle it occasionally misfired/idled rough, but the amount of oil does concern me. It also did have an engine misfire CEL.

I've tried to search and it sounds like it could be anything from the valve cover gasket to the PVC system to a more serious blown seal. Is there a rough process I should use to determine the culprit? I didn't really want to replace the valve cover gasket/take it off, but I assume I should start there. Having said that at some point I might just have to call it quits as the car does have 220k on it and it's getting to the point where it probably needs to be replaced. So I guess a better way to phrase this is, are there more serious issues I should look out for before dumping more money into an old car like this? Thanks for any help.

LeX2K

You need the classic valve cover* gasket job. Cover gaskets, PCV valve and any hoses you find that are brittle. Also replace the coolant crossover pipe. Have a good look at the coil packs oil contamination cooks them over time. Since the firewall side of the engine runs hotter lifespan is shorter on everything swap the front coils to the back. No guarantee they are all good of course.

At your mileage the oil control valves could be failing, very common

15330-20010 NO.1
15340-20010 NO.2

* valve cover is really a cylinder head cover

1 is firewall side. Drop your VIN here to get part numbers
http://www.japan-parts.eu/

I've had good luck with NGK coils, Rockauto considers Hitachi premium anyone here use them?

fortitude

If maintained, these cars run for a long time. Mine has 289000 miles

For the valve cover job, include 11193 - GASKET, SPARK PLUG TUBE
This covers the spark plug tube's connection to the valve cover. The other end of the tube is force fit into the head & rarely is the cause of oil leaking into the tube

Spend the money and go OEM for the gaskets

The valve cover bolts - the design has a built in crush washer. Search the forum - some have re-used (using an extra washer to make up for the used "crushed" washer), etc. If you decide to purchase new - get bolt+washer combo (90080-10288?).

If you plan on doing the maintenance on the car, I highly recommend getting the official repair manual from Toyota
HERE is the link. it covers diagnostic procedures, replace repair processes, torque spec, etc... For the brief time investment of saving the files & $25, it will save your hours of time and many dollars from firing the parts cannon

LeX2K

That's the correct bolt as seen here
https://www.lexuspartsnow.com/parts/...080-10288.html

Don't buy from that site!!! Used only for the image. You can actually buy just the crush washers but they can't be removed or installed without damaging so offering them for sale makes no sense.

Arsenii

I was reluctant about it at some point before the ... events .. described here. You will for sure know if a Solenoid fails, it won't be easy to miss, but it would render the car inoperable in that case, so whether to replace them right away is up to you. Considering my experience and the price for those, it may as well make sense to have them on hand if needed, depending on how long you want to keep the car.

As for the Coils, I would start by inspecting them, especially the Rubber boot on the end, as it can get affected by oil, dry out and develop cracks that may allow the spark to hit elsewhere aside from the plug, Denso does sell the Boots for those coils separately.

In a vacuum, yes, I would agree with it, but me being the one to always suggest to go OEM where possible, I went and got Mahle gasket kit after the Fel-Pro fiasco (see thread linked above). The price for OEM when you assemble everything is just a little tough to swallow, especially for what it is, and especially if you are not planning to keep the car for long. No leaks so far, even if not too much time has passed since then.

Yeeeeeep, ask me how I know.......

They honestly don't even seem like crush washers, it feels like there is a piece of rubber jammed between two metal plates, most likely to absorb any vibration or heat expansions in the engine. If you are worried, you can always do what I did and get a bunch of those bolts from a lower mileage car at a junkyard, 3MZ, and I am pretty sure 2GR all have the same bolts, so it shouldn't be a problem.

Hope this helps and best of luck!

ChrisEvo8

It's actually my mother's car and she's retired and doesn't drive too much, so I'm hoping to squeeze another 40k or so miles after this. Until recently I lived across the country so it's a little behind on some maintenance and while it's still a good car, there is a fair bit wrong with it. The transmission slips occasionally, the cats are dead (probably form burning oil), it's due for a new timing belt soon, most of the suspension should be replaced etc. While all these things can be replaced and none of the issues are THAT bad, I don't want to mistakenly spend more in parts then the car is worth. Even this started as a "Just spark plugs" and now I'm replacing the valve cover gaskets, intake gasket, PCV valve, coils, all the vacuum hoses, even the nipple on the IAC solenoid snapped off just due to age and the hose being seized on it. While I've been working on cars long enough to know this is just how it goes with older cars, I just feel like it's death by a thousand cuts with this and just looking around the bay, I see all sorts of things that should be done ideally, but again cost just adds up. I do agree that Toyota/Lexus make great cars though.

Having said all that I might just do a compression test to see how strong the engine still is and go from there, but the transmission does worry me as I tried new fluid and that didn't really help and from what I understand the planetary gears on these tend to go around this mileage and rebuilding a automatic transmission is one of the few car things I have zero experience in and it doesn't look easy :-0. I know I could probably find a used one somewhere, but that has it's own issues.

Originally I had the bought the Haynes manual for this car and man is it terrible. One of the steps for the plugs was a one sentence "move things as necessary" or something to that effect which totally caught me off guard when I opened the hood and realized what that actually meant. I have found a shop manual now though and it's MUCH better.

Having said that and I'm not trying to say you're wrong, but I don't see any mention of crush washers for the valve cover. I don't recall seeing them when I took them off although that could have been a crappy/lazy mechanic prior or the washers may have been seized together and I might have thought it was a flanged bolt. I feel as long as I torque them correctly(it looks like 8 N*m, several passes, etc.) and use the correct packing sealant, I would imagine it should be okay. But I'll have to search the forums a bit, so thanks for the heads up.

LeX2K

Valve cover bolts are technically one time use, to be blunt it's a poor design. If you use them again they won't apply enough force on the valve cover and you'll probably have leaks, or you might end up snapping them off. On the transmission if it is indeed slipping then I'd think twice about putting any money into the car, tranny failure and you have a nicely serviced and repaired brick.

Pull the front valve cover and post some pics I'm curious if the engine is full of sludge.

I add stainless steel washers to the original bolts.

ChrisEvo8

Thanks for the tips, yeah I don't want this to come off as rude in anyway as I realize what forum I'm in, but for cars like my Evo I always use OEM or better, do everything by the book, replace everything etc., but for my mom's grocery getter I'm willing to take some short cuts. So I'm glad it sounds like you're on the same page I am. Obviously I would never want her to get stranded anywhere, but these cars are built like such tanks I feel like it really takes a lot for that to happen, I have no idea how it was running as well as it was given the amount of oil there was.

I am thinking I'm just going to replace the three coils on the firewall side as they've been soaking in oil for who knows how long and the other ones are super easy to get to so I can do them later if it comes down to it. I was also going to get that Mahle kit, as OEM is just a tad rich for my taste given the circumstances, so I'm glad that sounds like it's serviceable.

It sounds like I will have to look into these bolts/washers a tad more though. I have plenty of new crush washers/regular washers that are JIS spec, but these do look rather odd for a valve cover. I've seen similar style bolts used on downpipe connections from turbos IIRC, but I don't see why Toyota put them on the valve cover as I can't imagine thermal expansion being THAT bad, but they clearly know more than I do about their design.

ChrisEvo8

I might not get to it until this weekend, but will when I do get to it.