Death rattle 2012 prious

leak down test: search how many miles on her? egr cleaned?

 

Well if you're not losing any coolant then you're Not having that issue due to coolant ingress. Condensation is a stretch . More like a flood. But ya better scope the gasket surface internally.

 

I have the same thing going on. No coolant loss. I follow the Car Care Nut. He is is a 20 year Toyota Master Tech, who opened up a Toyota only shop in Chicago. In his head gasket video, he show that when you pressurise the cooling system and look into the cylinder,you only see a couple of drops of coolant. Thats why you can have a missfire in the morning and then the coolant burns up and the car runs fine.

 

Yes I'm well aware I have met same tool and seen same many times only on certain engines mind you .I personally try n steer clear of problematic engines regardless of the vehicle it's sitting in . Unless in the grand scheme of things we already have worked out that were changing it to . And do on.

 

By the number of times that you have misfires (rattle) after doing a cold startup of the car. If it only happens one time, it is condensation. If it misfires several times during a week, then it could be coolant seepage past the head gasket.

How many miles on your Prius?

 

It is very possible and even common to have an occasional severe startup rattle due to an hg leak and not lose a noticeable amount of coolant.

It is also common in the early stages that the car passes a leakdown test and a combustion gas in the coolant test. Combined with no obvious coolant loss, many throw $1000 worth of plugs coils and sometimes injectors at it with no longterm results.

When it gets advanced you then start losing coolant, fail a combustion gas test and sometimes see white smoke from the exhaust when reving while parked.

The dual view borescope looking for steam cleaned pistons and sometimes coolant drips is definitive. Engine cold, coolant pressurized with borescope for possible view of coolant drops.

Car Care Nut HG Borescope at 660s

It can get worse when advanced hg is ignored