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Oil leaking into spark plug tube, need help!

84K views 9 replies 8 participants last post by  brianappj  
#1 ·
After a long trip I checked the oil in the engine and realized I need to add a little. While looking at the engine I noticed the #4 spark plug wire was lifted up a little from the others. It looked loose, so I pushed on it, but it wouldn't go down any more. So then I pulled it up and off. It was covered in oil. I went to take the spark plug out, and it was coverd in oil, and so was the socket. There had to be at least a table spoon of oil on the upper part on the spark plug in the spark plug tube.

Now as far as I can tell is the tube casted to the head? Or does it thread in? I checked the nut at the top of the tube that holds the valve cover on and it was tight. I took the other plugs out and they didn't have this problem.

So my question is where is the oil coming from? And how did it get there? The spark plug was also tight? The car runs fine, and there isn't any oil on the top of the engine. I'm going to be replacing the spark plugs and the wires, since the boot on the #4 is broke off. But I want to fix this before I put new wires on, so I don't wreck that set.
 
#3 ·
My other car had oil in the tube. The spark plug gasket had gone bad and started leaking. Replace head gasket and spark plug gaskets, replace spark plugs, and plug wires. I let mine go for a few weeks to save up the money but don't let it go too long. The spark plug will eventually foul out and cause misfiring.
 
#4 ·
On the 1997 I4 Camry we have (Gen4) there is a spark plug tube seal for each spark plug. It is like a large rubber grommet and is held down tightly to the spark plug tube by a large nut (30mm). If this nut is not torqued tightly enough, this could also cause a leak. The kit for an I4 valve cover and 4 tube seals was only about $25 here locally at an imported auto parts store. Even after torqueing the nuts correctly, it pays to check back on them after a few days and make sure they are still tight enough. Hope this helps.
 
#5 ·
The spark plug tubes can get oil into them 3 ways-

One, the way that ycartf described - the rubber grommets at the top can leak
Two, the seals at the BOTTOM of the spark plug tubes can leak. To replace these, you will need to pull the valve cover off and remove the tube (with a pipe wrench, usually).
Three, when you pour oil into the engine through the fill hole, its very easy if you miss for it to get around the boots and fall down the spark plug tube.

Good luck with it!
 
#7 ·
Got it fixed

Well I did the work last night. I think I have it fixed, but to know for sure, time will tell. So far there are no leaks with the short test drive I did after I was done with the work.

I ended up putting new, plugs, wires, spark plug tube sealer, spark plug tube upper gaskets, and head gasket on. This was all $160.00 through the dealer. Not bad, some parts were cheaper and some more expensive, than a car parts store. I spent about $10 more that I would have by buying everthing at the dealer. It saved me from running three different places, and I have all genuine toyota parts.

I'm going to do a write up with pictures, as soon as I get my camera back. I figure most of the gen 4 5S-FE's will have about the same mileage mine does and a lot more people will be experiencing this problem soon. So since I've done it I will get the info out to those of you who will being doing it in the near futre.

Just wanted to say that it didn't seem like most people knew what was sealing the bottom of the tubes. It is just thread sealant. It has to be removed and new applied, and threaded in.

This was a fairly simple task, took 1.5 hours, with taking pictures, and removing the hood (only way to go, more room, more light).

For more details look for my how-to...coming soon!