Driver side middle

2007 GS350 132k miles....So doing a plug change today, almost all plugs had at least a little but of oil on them. But the driver side middle plug was by far the worst.. drenched in oil. Could this be the valve cover gasket? Spark plug tube? Something more serious? Car runs like a champ but definitely concerned.

Thanks.

 

Take a good look at the area above this plug for signs of oil leak. If not obvious leak, clean the entire area and come back for a look after after several hundred miles for leaks. At 132k miles, many things can leak. Valve cover gaskets being one possibility. Plug electrodes look good.

 

Rings could be dirty, had the same at 215k when I pulled them. Poureda little seafoam into the oil ran it for an hour, changed the oil. Filled and out a new filter on, drove car for like an hour. Changed the oil and filter again. Changed the plugs and seemed to be fine. I pulled the plugs 15k later to check and they had no oil that time. Car also smokes less since. Something to try!
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While hard to tell, there is a small amount of oil pooled up above the plug. Car was overdue for a change, given that electrodes look decent and oil pooled on the outside it's probably not something internal?

 

Food for thought, thank you! Was thinking of Seafoam anyways.

 

Spark plug tube seals. Need to off the valve covers to get to them so if your valve covers are leaking, it’s the ideal time to get to them

 

I agree completely. Definitely not internal. It sure is clean in the immediate external area. Disappointing as this means more research. I'm not familiar with getting a look behind those metal tubes that guide the plugs in but it seems reasonable the oil is coming from behind them or another area where it runs undetected to the plug tube. Like a roof leak that shows up on the ceiling 20 ft away from the source instead of directly above. i'd use the forum search tool for GS and IS350 as the engines are basically the same. I've found the search function to be weak in that you should look at page 2, 3, 4 if you don't find an answer on page 1 of search results.

 

pretty sure it's valve cover gaskets that would allow oil to pool in the plug holes. so a search of :valve cover gasket" would likely give you answers. I did a bit of searching and found that there are gasket kits that contain multiple gaskets and you should also replace spark plug tubes as well.

 

Ya def buy a gasket set from the dealer just for that side thats leaking and make sure it includes the sparkplug seals. You might need rtv silicone on the edges of that seal. I like using a motorcycle sealant called yamabond or hondabond

 

Its the valve cover gasket. there is a DIY on youtube( ). Its a 3-4 hour job if you do it. And the gasket costs around 40$ on eBay. Or 600$ at the dealership.

But at least I have a bigger problem than yours. I found my car burning oil a lot and i can smell it through AC vents. I ordered a valve cover gasket and then found that it is a timing chain leak. I am already broke AF due to Corona and I lost my job and now its a 3k$ repair as the engine has to come out I wouldn't have repaired if its a small leak but mine is bigger

 

Sorry to hear about your situation! Hopefully things look up for you! Did you mean you are leaking at the front crank seal thats behind the timing chain, or camshaft seals?

Maybe try an oil product called Blue Devil, many auto parts stores didnt sell it to regular customers but only to commercial accounts. My old mechanic friend sore it is amazing stuff at sealing oil seals. Maybe give that a shot and see!

 

Very sorry to hear that my friend. Appreciate the tip and info, I'm going to leave it for the time being and have an indy shop do the work as I'm not that mechanically inclined to rip off valve covers. Hope things start looking up for you and you can get it taken care of. Is that a common issue with these cars? I'll pray it doesn't happen to mine.

 

Yes that's the one. I found a shop near me who will do it for 2k$. I gave the car for the repair as I am thinking to keep it for 2-3 years more.

 

As the car becomes old, valve gaskets are prone to damage. As a cheap alternative you can try "Lucas Stop Engine Leak" which you can find at any automotive store or Walmart near you. Cheap fix and works well if it's a small leak on valve cover. But i suggest you to change it. Its pretty easy job. All you need is some set of tools and 3-4 hours of time.

In my case the timing chain gasket is not made of silicone rubber. Its a different chemical which hardens unlike rubber to seal the parts together. And there is no other way to fix it using these additives.

 

Plug gasket likely. Same issue on our GS460 but we also just did oil flush to see if rings are gummed up as well will pull plugs soon and see if it's fixed.
I don't see why people do valve cover gaskets when the tube is leaking though.

A few members often recommend testing/replacing PCV valve.