2014 Prius V want to avoid head gasket problems

Sounds like a good plan.

Is it just the Engine Coolant Temp sensor? Or are there other live data points I should watch.

Also, side note: Is this piston head indicative of steam cleaning from coolant? Or just a clean piston? (Maybe the previous owner did an engine treatment or something? Idk) there are no other signs of HG failure so it would seem odd to me that it’d be a coolant leak, but it does seem rather clean for 166k miles

 

Then u have the traction battery..... the master cylinder and pump.... $4000.... plus the inveter can blow at anytime......

The cars are junk.................. when older.............. sure low miles seems great........ you have been warned...... keep reading on here........ and other websites..... save your self huge mental and financial pain.

 

That's way too clean for 166K miles. How does it compare to the other 3 cylinders and look at the spark plug burn pattern and color.

 

Steam cleaned

I would suspect head gasket sealant was added for a temporary fix. It usually does a great job - for a few months. I would suggest if it is still running smooth on cold startup by March you bought a good one.

 

I checked cylinder 1 and 2. Similar state, didn’t check 3 and 4 because the spark plugs were all similar and I was defeated that night haha

 

Those plugs could be original.

 

Damn

So no need to panic and do anything right now about it? Just monitor for further symptoms of typical HG failure and if I make it to March I *should* be okay?

Ugh

 

Yeah, my thought as well. Threw some new ones in while I was in there

 

They may have been burning some additive or seafoam. Only time will tell. Some of those harsh additive can destroy your CAT.
The real silent killer is running that engine hot - that electric water pump isn't going to tell you it's failing; but that HUD will give you advance warning to sniff around. Normal operating temperature is 185F to 205F; even on the hottest summer days and long hill climbs. Touching 210F should be a rarity. Just look around to see if that operating temperature is warranted.

That spark plug should be black carbon to white ash; don't know what that brown stuff is.

Good Luck....

 

Od

Odds are in your favor by then.

 

Question that came to mind:

If there was an active coolant leak causing steam cleaning of the piston, wouldn’t the spark plugs also be abnormally clean as well?

 

So far with the new water pump, it doesn’t appear to go above 190ish which is a good sign. Will continue to monitor.

Also, everything that I’m reading online says the brown spark plugs is a normal sign of a healthy engine, so I’m not sure what to make of the condition of the plugs.

 

Head gasket sealer can stop an active coolant leak. These engines are also known to burn oil. The pictured plug looks like chunks of buildup have fell off the electrode.



Again you will learn more as time goes on. Watch the passenger side coolant reservoir and the oil level.

 

By the way these engines don't exhibit "typical" hg symptoms in the early stages. Leakdown and compression will be fine, combustion gas in the coolant will be negative, coolant loss will be non existent and no milky oil.

Early symptoms are very occasional severe rattling and shaking on cold startups. Occasional can mean weeks. Then an occasional misfire code which may present on random cylinders but clears within seconds and the engine runs smooth the rest of the day and maybe for several days.

The severe rattling is enough to convince people to do something. It sounds like rod knock but it goes away quickly. Shops not gen3 Prius fluent fire the parts cannon, plugs, coils, egr cleanings and maybe injectors. Each time there is a warm feeling for days it was solved. Only to return if the very slow early leak remains.

Borescope is the definitive test. Steam cleaned pistons don't normally happen just by using additives. If the leak is active a borescope on a cold engine with a manually pressurized coolant system may show drops of coolant coming from the gasket into the cylinder. If someone used sealer, no symptoms or coolant drops.

This video shows a cold engine borescope test using a quality articulating or dual view borescope.

Car Care Nut HG Borescope at 660s

Once again, don't worry about it unless you get the symptoms of severe rattling and shaking that goes away for the rest of the day.