Violently shaking on start after maintenance

Did they clean the MAF sensor during the service?

I'd be very reluctant to have Pep Boys do a major service, involving coolant and brake fluid. Both are tricky, require repair manual access, and/or techstream.

FWIW, the description and video sounds like head gasket leaking.

 

the only thing i see that could be related is spark plugs. after you get the dealer evaluation, if it is determined that it was related to the pep boys work, i would absolutely demand a refund and/or pay for repairs.

if the manager balks, escalate to corporate. they have a reputation for not putting oil back in after draining, but do pay up for engine replacement.

edit: or maybe they overfilled the oil?

 

Sounds like a classic headgasket issue. Usually they shake on cold starts for a minute or so unless they are really bad. Not every time. Look for reduced coolant levels in the passenger side coolant reservoir. I would definitely take it in for a dealer diagnosis. Unfortunately the 2010-2014 Prius engines are starting to have a lot of these. The repair could be expensive especially at a dealer. Consider alternative shops if it is the headgasket.

 

I don't think 2015 is immune from head gasket issues; just less prone to excessive oil consumption.

 

First thing: Check the clear plastic engine coolant reservoir. Make sure there’s fluid inside. Don’t drive the car without coolant.

I don’t think that even a poorly performed service will cause the head gasket to fail (unless there’s no engine coolant, then... yeah). But the car should be seen by a competent Prius mechanic. At a minimum, get a code reader and look for any error codes.

It could be something simple, like a MAF or MAP sensor cable wasn’t re-attached.

 

So the engine never violently shook before?
What spark plugs did they install (listed on receipt?)?