Hello, Saturday I drove about 30 miles then sat about 1-1,5 hour somewhere, when I hit button it started rough with noise and Check engine light came on. Drove back home and parked. There is p0303 error code. Sunday night the light went off still was giving code. Monday i took it to one mechanic, he said my waterpump leaks and there is water in sparkplugs. He Recommended to use blue devil head gasket sealer immediately, drive about one week and come back for tune up. Tune up means waterpump replacement costs about $450. No idea how he is so certain without touching anything. (Second mechanic told me this how he knows the water issue without checking out sparkplugs) Second one thinks ignition coil and spark plugs replacement can fix the issue. Cost about $170 (coil 110 + plugs 60) parts and $100 labor. After stopping by this mechanic code disappeared and another one I went didn't want to say something because there was no code or light. It has 204k miles with regular mobil 0-20w oil changes. I read many stories about this case also injectors and manifold may cause this. Not everytime but it still kicks for 3-4 seconds almost 1 of 3 starts. Have no idea where to take it and what to do. Thanks in advance.
Thanks for the reply. This morning started rough again lasting 40-50 seconds and check engine light on again. Obd code changed to p0301. Cylinder 1 misfiring
Is the coolant level low???? If not, you may just have a dirty intake plenum and egr system. In cold weather, water condensation and oil sits @ the bottom of the intake plenum. On start up, oil/water is sucked into the combustion chamber causing this scary knocking sound. When it burns off In 5-30 sec, the knocking is gone. If the coolant level is low, you most likely have a blown head gasket. The knocking comes from coolant being present in the combustion chamber. Liquid is an incompressible solid causing knock. This knocking with destroy the head gasket! A new head gasket or used motor will be $$$$.$$! 80$ is a big gamble if the bluedevil does not hold. I personally would not use it. It will clog the radiator, water pump, heater core etc. I think all the mechanics you talked with are wrong. It will end up wasting your time and money. If you are mechanically inclined, I would take the weekend to do it yourself by installing new plugs, clean egr cooler/piping, intake plenum and install an oil catch can. I actually got done cleaning/emptying the oil catch cans today on both of our prius (2010/2011), checking all fluid levels and adding more air in the tires. It's cold out here in Maryland. I know the prius is a a low maintenance car but keeping the egr/plenum/pcv system clean is critical for proper engine performance and reliability.
