Oily seepage on screw

Looks to be at passenger side end of engine, looking down and to rear of engine, a bit past the engine mount.

Hard to tell, could be timing chain cover (the whole end panel) has a slight leak, or oil pressure sensor: it's just round the back there IIRC.

Taking off passenger side wheel, and a few of the wheel well back wall plastic panel fasteners, then prying back the panel, you might be able to see better where the leak starts.

 

My guess would be the oil pressure sensor, which is sort of on there hand-tight. There have been many threads however about seeping timing chain covers. Pull the panels and take a look before cleaning it up.

 

Do you park on concrete?
Any signs of oil under the car?
Any work done on the car recently?

I'm thinking timing chain cover - and no action required other than monitoring.

Good Luck!

 

if it's not dripping, i'd ignore it

 

Early stages of a Timing Cover leak.

The mileage is typical for when this starts to happen.

 

I just removed maybe a couple of the fasteners holding the plastic panel, the readily accessible ones. That's sufficient that you can then flex back the panel.

 

Oily seepage...reminds me of those Olestra warnings. Yes...yes...I am a middle aged guy with the mind of a 13 year old.

Seriously though, I think I have a similar problem on our 2010 liftback. It has around 120K on it. Oddly enough, no problems like that on onr 2012 Prius v (wagon) with around 150K.

 

Timing chain cover reseal is pretty involved. Dealerships have been charging $1700 range for this. Not sure what the book way is.

Simplest is to leave engine in place, remove the engine mount, and I think the valve cover too. The flywheel and oil filter bracket too need to come off. Maybe the water pump too??

Then pry it loose and remove. You for sure would want wheel off on that side, and that wheel well liner panel completely out of the way.

After everything is clean and ready, there is a complex form-in-place gasket procedure, with very limited time since it sets up quick, and then about 25 bolts that are to go back on and be torqued, again in very short time.

I would think the time parameters are near impossible, you should just work fast and be careful/thorough.

I've got Repair Manual info, can post later.

Bottom line though, if it is the cover, and minor leakage, just live with it?

 

At your mileage, you are probably a few years away from needing a head gasket job. Not all of the 2010's will suffer from this issue, but a number of them do.

I would leave the seep alone. It is not worth addressing unless you feel like spending 6-8 hours of your Saturday doing the repair.

 

Repair Manual info attached. There's a dizzying number of bolts, various torque values, and the FIP gasket install diagram is a little nuts. I would think you apply the lateral dabs (at engine split lines) on the engine, and the rest just on the removed cover. I believe it's supposed to be applied and on by +3 minutes, and all bolts torqued by +15 minutes. There's a few O-rings and gaskets that it wouldn't hurt to replace, too, if you can figure out the part numbers.

Still, it's a lot of work, too much if it's a minor leak.

 

have you cleaned the egr circuit?

 

With 135K it'll be getting along. Likely not terrible, but definitely worth doing.