2011 Prius acting very strange

welcome!

hard to believe no warning lights. i think i would check for codes just in case.

 

I would guess your coils are fine and that you need to clean your EGR circuit along it's entire length. Intake manifold large EGR port and small ports to each of the 4 intake ports, EGR pipe, EGR valve and EGR cooler. This entire circuit needs to be free of carbon obstruction. There are scores of threads regarding this and subsequent head gasket failure when left too long. @NutzAboutBolts has very well done instructional videos posted to their sticky in this forum.

Your mileage is low enough that there's a solid chance your head gasket is ok, but it absolutely should be ruled out. Check your engine coolant level in the translucent bottle on the passenger fender, and monitor it over coming days to be sure it's not dropping by the day. If it stays at an exact level, you should be in the clear and the EGR cleaning should remedy the "misfire-like" symptoms. If the coolant level is dropping, you'll want to proceed with testing for failed head gasket.

This said, coil failure is a rarity with these cars, especially at your low-ish mileage. It's also very unlikely a coil(s) causing symptoms you describe would present without the check engine light and an accompanying P030x code(s).

Good luck. If you need an independent mechanic's help, please post your town or general locale in Ohio.

 

Sounds like it could use an EGR cleaning and swap out your PCV valve.

 

EGR cleaning

 

What's with that? Just Beelzebub waiting in the wings, or?

 

The devil smells like sulfur ?

How do you know that?

Or is that something you’re not supposed to share ?

 

Don't laugh boys, sulfur smell seems to be an emerging symptom of turd gens which resolve via divine intervention. Nothing says higher power more than the old dealer EGR valve swap...

2010 Prius: Engine/Battery Rattling, Pulsing at Cold Start/Low Speeds | PriusChat

Kidding of course. Entirely possible both of these cases are down to a worn out EGR valve and some bad, midwestern gas.

 

Yes and yes (although for question 2 I would say cleaned not checked).

Good luck and keep us posted .

 

A quick google search brings up Christopher’s in Tallmadge. Had good reviews .

Might be worth a call before they close today for the weekend.

 

Sulphur smell comes from unburned fuel accumulating in the catalytic converter. Get on the freeway and put the car in power mode and floor it. Accelerate from 55-75 and repeat. It is also known as the italian tune up. Driving the car in eco mode, short trips, too slow, too low of rpm can cause this sulphur smell.

Cleaning the egr and intake manifold would also be great. An oil catch can wouldn't hurt either

 

**apologies, for whatever reason I'm not able to post my links to amazon for the pipe brushes and E8 socket. I'll try again in the morning in case it's a priuschat issue..Meanwhile, you can plug the descriptions into an Amazon search for proper links**

It's not technically difficult, just an exercise in tediousness. If he did the plugs he can do the EGR circuit cleaning, and will get another opportunity to pull the wiper cowl. He should plan ~6 hours or so minimum to avoid having to rush.

I have a set of aquarium-style pipe cleaner brushes that make cleaning the 2 different size EGR ports of the intake manifold quick and thorough:

JBtek 10 Piece Nylon Brushes for Drinking Straws, Glasses, Keyboards, Jewelry

Then 3 or 4 cans of Brakleen red can for attacking the EGR cooler and Oxiclean if you're going for the like-new finish.


The most important tool, an E8, external torx socket in 3/8 drive for the valve/cooler studs:

DEWALT 3/8" E8 Extension TORX Socket

A gallon of Toy Super Long Life coolant to top up or 2 gallons if the car is due for it's full, 100k engine coolant change. All gaskets can be re-used but only total in the neighborhood of $35 or so if you want to go the type-A route. Credit to Ray for the tidy gasket part # pdf:

file:///G:/Mike/car%20tech/gen%203%20prius/engine/124568_Intake_Manifold_Gasket_Item_List.pdf

 

You can completely avoid coolant loss when removing the EGR cooler:

Drain about 2 liters at the radiator drain spigot before starting, into a clean catch bucket of some sort, preferably with 2 liters marked. This drops the coolant level below the cooler. When the cooler coolant hoses are disconnected, there will be no spillage.

Then, when lifting out the cooler keep it in the as-installed orientation, then tip it out over that catch bucket. There'll be maybe a half cup of coolant trapped in the back corner, that couldn't drain.

Then when done, just pour the drained coolant back into the reservoir. 2011 Prius still have the coolant vent spigot at the top: when pouring the coolant back into reservoir leave that vent open, until coolant rises up enough to flow out, then shut it. Burbing the coolant hoses a bit as you're pouring helps, I think.

Level in reservoir may be a little high, but should return to normal with day or two of driving.

 

Sulpher, sounds like diesel.