Help what could have happened

The check engine light stores error codes that will indicate what the problem is... Try not to be upset with the boyfriend, he was trying to help and hasn't done anything unreasonable to help make the car work better. As in he didn't break it because it was already broken.

First step it to get an OBD2 device so you can use a phone app to read and clear error codes using an app on your phone like the Dr. Prius app. Once we know the error codes and how long they take till they come back we can give you repair options. Here's a good price on an OBD2 device: Panlong Bluetooth OBD2 OBDII Car Diagnostic Scanner Code Reader Check Engine ... | eBay

 

how many miles on her? you need to clean the egr circuit

 

Please, never ever ever go back to that garage.

Did you bring in the car?
Besides garages taking advantage of "everyone" in terms of repairs, there are garages (/owners) that target females, as a group they can take advantage of in terms of repairs.

When I was a teenager (and the Mammoths were still around ), the local garages that I was "associated with", made it a point to treat everyone honestly and with respect.
However, imho, they were in the minority.
It's hard for any small business. It becomes all too easy, to take advantage of people - just because.

 

Take a video of the car/engine at startup, and then when the car is put in Drive, and the noise stops.
NOTE: Always stand to the side of the car/engine, if someone is going to be putting the transmission in/out-of drive.
Upload the video to youtube.
Post a link. It may take 12-24hrs for a moderator to approve the post.

As mentioned above, you must read the engine/car codes to know what's causing the error.
Iirc, on my car, there are many hundreds (likely over a thousand) different values that the scan tool can read. And, hence, can result in some sort of error (not all errors light the check engine light).


Good Luck.

 

If your spark plugs were wet when you removed them, any mechanic would be able to tell you it's not good news. Your car being a 2011 Prius, we can 100% tell you that you have a head gasket failure. You need a new engine or fix the head gasket.

 

Agreed. Wet plugs. Rattle on start. Over 150k miles. Trouble codes (unread by the shop for some strange reason) that almost certainly include engine misfires. The only head gasket symptoms not mentioned is white exhaust smoke and milky oil.

I'd check the codes, look at the exhaust and oil. Most likely, you'll see one or all of those symptoms, too.

 

Bummer

 

The engine is running rough because you have engine problems... That's why there's a check engine light! The idiot that blamed the motor mounts rather than doing and engine diagnosis needs to be pressured into refunding part of your money for doing unnecessary work. Get online and file a Better Business Bureau complaint. It's a great way to hold scammers accountable!

 

Welcome to high mileage gen3 head gasket problems. It does not present in a normal manner confusing many average mechanics. $2,000 to $7,500 depending who fixes it or if you want a long term fix. Did you pay more than $5k-$7k for this car?

 

Time to trade in the boyfriend

 

I was wondering how long it was going to take the seafoam in the battery to clear

 

Why are people saying that "the car is junk"?


As I understand things:

• Initially...
  
• Sometimes, the car had/has a rattle on startup.
• The rattle would often stop once the car was put in gear.
  (Codes clearly were not read.
  Not clear is there was any check engine light.
  Not clear how long the orig poster had the car.)
  
  (next sequence isn't clear)
  
• Low Life scammer scum garage changes motor mounts. (Based on what? I wonder if they even touched anything.)
  (Of course, this had no effect on the rattle.)
  
• Boyfriend sprayed seafoam into engine.
  Engine wouldn't start.
  Boyfriend changed the spark plugs.
  The spark plugs were wet. Not clear if before/after the seafoam.
  
  
• Engine now starts.
  
• Now, there is an engine check light.
• Now the engine runs rough.

For people that know the Gen3 better, won't a cheap $15-$20 Amazon code reader, read and display some codes, any codes, related to a bad head gasket, or clogged EGR?
At the very least, a cheap OBD-II code reader with live data will show the fuel trim levels.
Imho, it's very easy to hook up a cheap OBD-II reader, that someone on youtube has shown how to use.
Verses: Doing the correct chants, and live sacrifices to the Google/Apple/Tech deities, to get the OBD-II phone apps to work properly.

Maybe something like this scanner:

Code:

https://www.amazon.com/MOTOPOWER-MP69033-Universal-Diagnostic-Protocol/dp/B07Z3HB7DR/

MOTOPOWER MP69033 Car OBD2 Scanner Code Reader Engine Fault Code Reader Scanner CAN Diagnostic Scan Tool for All OBD II Protocol Cars Since 1996
#1 Best Seller in Code Readers & Scan Tools
Price: $25.00


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Most of the time you are blowing white smoke and watching the coolant go down in realtime without codes. Occasionally a random misfire code appears and quickly goes away. This generates shop revenue when the customer wants new plugs, coils, water pumps and or injectors. If its a clogged egr it has to be totally clogged to code, but this has no correlation to a bypassing head gasket on any given engine. If it is a coil or plug the misfire will be persistent on one cylinder and move if you move the part.

However a borescope tells the tale even without codes.