I recently bought a 1996 Lexus ES300. Upon purchasing it, I did a full service tune up (changed air filter, plugs, wires, oil, tires, brakes, and rotors). Everything seemed to be fine, as it ran smoothly. About a week after i did the tune up, i checked the oil to see was I losing any, and low and behold, I was short about a quart. So i proceeded to check the oil every other day, and I found that I was consistenly consuming 1-2 quarts per week. I didnt have any leaks, and I knew it had to be purely consumption. So a few weeks later, a spark plug started to misfire. I did some research and found that it could be a bad valve guide and seal, which allowed oil to seap into the combustion chamber and foul out my brand new spark plugs. From any of your experiences,can you advise on if you think this is the problem? If so, how much does it cost to get valve guides and seals replaced? Is it something I could/should do myself? If this is not the culprit, what else could it be? Your advice is appreciated!

 

I don't know how mechanical inclined you are but all jobs can be done by yourself!!

But if you are asking if you should do it, from the sound of it, you shouldn't do it.

It can also be:
- clogged PCV
- bad piston ring

 

Unfortunately, it sounds like you didn't do your homework, i.e., a thorough inspection of the car prior to purchasing. 1-2 quarts of oil per week is incredibly high. Replacing bad piston rings and/or bad stem valve seals is a major job, therefore not recommended for non-experts.

 

Pull the front valve cover. Check to see how much sludge is evident. If there is an obvious build up of black sludgy looking stuff in the valve cover do this. Remove the rear valve cover and look for the oil drainback holes located midcenter in the head casting. Also look at the front head for this. Take a long screwdriver and clean out the oil drains. Clean out as much of the sludge as you can, and get it all, and replace the valve cover gaskets while you are at it. I'll bet they are hard as a rock!

You will need to remove the oil pan and clean in there as well. Making sure you get all of the broken up pieces of sludge you shoved down from the top. Clean the oil pickup tube and screen by taking it off and cleaning it. Make sure there is nothing inside of it.

You can probably save that engine if you do it now. I'm not sure of the comments above about the clogged PCV or a broken ring. A clogged PCV is not going to burn oil! How can it? It's clogged! A broken ring is well, just unheard of.... Whats going on is the PCV system is picking up the oil in the rear head. If the drainback holes are restricted, the oil pools in the head. The vacuum from the PCV is picking up that oil and sending it into the intake. The oil then pools in the intake and collects in an intake port, snuffing out your plug. Use the Denso plugs for it. Anything else will not work well!!!!

Take your time. This is a messy job but not hard by any stretch... Removing the upper intake will be the hardest part.

Good luck.

 

how many miles do you have on the car?

 

Synthetic oil will clean the engine pretty well...