P0300 0301 0303 misfire and engine knock problem

Especially if it has 150,000 miles or more...

 

The engines are the same. The transmissions and many other parts are different than the hatchback.
I have a quarter of a million on mine and have replaced almost everything except the engine.
Traction Battery
Master Cylinder and Pump
Both Water Pumps
Inverter
R&R The Entire EGR System including Intake Manifold and a Oil Catch Can.

 

I am sorry that you got lemon. Head gasket can be a problem in any car especially if you ever have waterpump or cooling problems and did not fix it on time. As rule of thumb, always do hydrocarbon check whenever you loose coolant after you found no external leak. Generally speaking, very rare 2013 up has head gasket issue compared to pre 2013. Often DIYer makes things worse than just let professional mechanics do the maintenance and repair. If there is any problem, let professional diagnose it, once you found the problem for sure, then you can DIY

 

It is not rare for a 2013 to blow the head gasket......... mine blew and two others that I personally know of.
This head gasket issue really put a black eye on the prius especially when purchasing used.

 

Good to know, but it is much less than pre 2013. 2-4x more often in 2010-2012. Less often does not mean 0 case.

 

Every time I see a gen 3 go by I know what the owner is in for if they keep it over 150,000

Gets great mpg........ but that's all I can say....

 

I am afraid the head gasket issue is common in the 2010-14 1.8L Prius engines. People buy the 2013-14 based on some reports on this forum and end up disappointed.

It is illuminating to read the OP's posts in this thread paying attention to the dates and emotional roller coaster. Disregard the advice to clean egrs, change coil packs, plugs, etc. The pattern of many 1.8L head gasket failures is in her posts and has been reported fifty times in this forum.

Starts out with a very occasional rattle, sometimes weeks apart. No observable coolant loss or white smoke. Egr system is cleaned with much effort and the immediate results are good. A few days later the rattles return. Plugs, intakes and coils with identical results. A few days grace each time only to be disappointed.

While not recorded by the OP this time, a coolant hydrocarbon check or leakdown test will be negative in the early stages. Later when its rattling every other day and coolant is down by an inch, the hydrocarbon test "might" be positive. A borescope test is usually definitive by then. At end stages with rattling at stop signs, white smoke (observable in the rear while revving), all leakdown or hydrocarbon tests are positive. Rarely will coolant be in the oil.

Initially hg leaks are slight, very occasional and don't present like traditional head gasket failures. Sometimes early teardowns don't have a physical break in the gasket but coolant leaks to the cylinder under the gasket. Apparently caused by minimal warping that is quickly sealed as the cylinder heats up. Uneven cylinder cooling design is a contributor. On occasion, a loosened head bolt achieves the same thing, typically after a repair. Worse case, a rod bends and eventually breaks.

Overall a flawed design that often points to the 2010-14 piston ring flaws which then aggravates a poor egr design. All redesigned by gen4 with the gen3 rings improved by mid 2014. Gen4 also significantly redesigned cylinder coolant passages and added an insulator.

Gen4 Cylinder Cooling Redesign

 

Hello, I was reading this thread and my car is having same exact problems. Did it end up being the head gasket? I've already put in over $2K in repairs and its still reading as cylinder 1 misfire. I'm at a loss on what to do. Thanks!

 

Your screwed..... it's always the junk toy head gasket..... total crap.... DO NOT PURCHAS A USED GEN 3 PRIUS!

 

Did you change the headgasket properly including checking the cylinder head and block? $2k is enough for head gasket job on independent mechanic. Don't put any sealers that will ruin the whole cooling system including heater core that cost more to replace than headgasket

 

What did you do for that $2K?

 

No repairs on head gasket yet. at 175k miles, the shop is recommending i replace the engine altogether. Now I'm debating what to do. I know nothing about car repairs and don't have any mechanic buddies.

 

They changed spark plugs (my prius is 2012 and at 175K miles), engine coils, EGR and water pump. The check engine light will be off for a few days and then turn back on. Finally they ran the camera and found the leak. They said its a very tiny leak in cylinder 1, leaking coolant. But at 175k, they recommend I change the engine altogether. After 2K in repairs, I'm just not sure what to do anymore. I have no car repair experience so everything will be out of pocket.

 

there's another current v thread member experiencing the same dilemma. 200k, but already replaced the battery and actuator, now facing 3-10k for a head gasket or replacement engine.

 

You should get your money back. Total WRONG Diagnosis............ anybody on here knows it the head gasket.....

 

It's such a common story, though. Maybe cus it's damn unusual to have head gaskets failing in droves, at low miles? To add insult to injury, when the mechanic sees a misfire code, on one or two cylinders, trying shuffling the plugs/coils around? Nah, change em all.

 

My recommendation for a reliable car with an engine that will make another 150,000 miles is to get a rebuilt engine. Preferably not yours given a preexisting head gasket problem.

It is interesting to see what Hybrid Pit in Southern Calif does:


This is the traditional, proven and reliable solution. Follow with 5k oil changes like your wallet depends on it.

 

Cylinder wall is generally cannot be honed in modern engine. If the wall is not too bad, replacing piston and piston Ring, valve seals are enough. I prefer 2015 used engines instead of rebuilt because the cylinder wall are often already bad when it consume oil before.

 

Similar issue. P0301, P0302.
Shuddering at idle.
Pulled the sparks. What do you think?
I could swap them around and see if the misfire moves, but I'm tempted to just replace them and hope for the best.
What's your favorite longest-lasting spark. These were NGK laser iridium.

 

What’s the miles? VERY likely the head gasket failing.

Boroscope the combustion chambers while plugs are out is a good ploy. If you can manage to pressurize the engine coolant system it’ll accelerate any coolant leakage (past head gasket into cylinder). Look also for exceptional clean piston tops in the cylinders with codes.

Be sure to clean the EGR system and intake manifold when it’s sorted.

relevant info in my signature; on a phone turn it landscape to see signatures.