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2009 Toyota Matrix Mysterious Oil Leak


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My 2009 Matrix is leaking a decent amount of oil. It seems to drip from underneath the radiator to the ground. But the entire under side of the engine is wet, and the passenger side axel and wheel well too. 

I heard that timing chain tensioner is a common place to leak, also it makes a rattle on startup for 1 second. Can this all be related? Any thoughts?

Thank you! 

4 Answers

If your car has a 1.8L, most often it leaks around the timing chain cover, according to the internet, sometimes the oil filter housing can leak.

I’d clean the engine and see where oil appears, or use Scotty’s method with UV light.

As far as the rattle, I wouldn’t mind it - it’s probably the VVT sprockets. But there’s always a risk that it’s something like a tensioner or other things that can cause damage if they go bad…

Clean it up. Then start it and get underneath and watch everything?

I thought about the filter housing as well. Would that really leak all the way to the front though? Seems like wind would blow it backwards, and even parked drip from there. Not further forward

Well, I’m unsure - but I did have a filter housing leak (in my case it wasn’t the engine, it was a DCT but it’s fairly similar holder design) on my car and oil did get absolutely everywhere…
If you’re unsure you can always use the UV dye method.


Your rattle on startup is the dreaded VVTi rattle. 


Video is for a corolla, but it should help understand what's going on.

Good video. Thank you. Any idea if the vvti rattle is something dangerous? And needs immediate attention?

Here he explains the vvti system and the rattle in-depth. But if you're going to address the timing cover leak, might as well take care of the vvti rattle. 



You need a leak dye test to pinpoint the leak.  Your timing chain is making noise and needs replacement.  Replacing the timing chain kit and new timing cover gaskets will probably solve both problems.

Not necessarily, rattle on startup is usually VVT sprockets, sometimes tensioners. most of the time a stretched chain won’t rattle only on startup.

I thought about the dye. But then you would run it and get underneath right? Because driving it the dye would blow everywhere and defeat the purpose, correct?

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Figured it out. The leak is actually transmission fluid. Coming from the metal cooler lines that bolt onto the radiator.