First time poster- I have a 2013 Prius w/ 159K miles. Day after a fill up from a service station I have used in the past got the violent sputter and shakes and got a cylinder 1 misfire code. The plugs and coils were replaced at end of 2019. Here is what I have done so far: - cleaned out EGR pipe - cleanes MAF sensor - moved plugs around then coil and code did not follow - cleaned out manifold and intake - cleaned throttlebody - removed injectors and cleaned them - then started to get the code for the random misfire on all cylinders - changed out all 4 plugs - added gumout fuel conditioner - later added STP octane booster - added Lucas Fuel Injector cleaner - replaces 12v battery I am now getting a code for O2 sensor as well and have ordered a new MAF and O2 sensor (figure what the heck with the cars age and milage) Still misfiring badly not as bad as it was in the beginning. I have been watching the oil and coolant and no apparent sign of head gasket issue (no coolant loss, no white smoke and no milkshake oil) car does not burn oil. Its quite a mystery was thinking about adding Heet to see if the gas I put in was junk and had water. Love to hear any other thoughts
When and if you do the head gasket, everything else will be good. Often the coolant loss is very minimal at first. Typically the rattle will clear within a minute and run fine after. Prius Knock Knock Who's There? Its me, Cylinder 1 Stage 1 Spark Plug and Coil Change Clean EGR Monitor Coolant Try Head GasketSealant Stage 2 Order a Motor from Japan Arrange Killer Install Deal Stage 3 Question Motor from Japan Stage 4 Decide to DIY Change the Head Gasket, Change Gasket Stage 5 Reconsider Motor if yours might have a Bent Rod
Unless the bent rod was accompanied by irreparable damage to the block itself, I would simply replace the rod assembly (P/N 13201-39185, $68-$98). Unbolt the AC compressor from the crankcase (3 bolts) and hang it out of the way. Get directly underneath the engine and unbolt the crankcase (with oil pan in place) from both the engine block (11 bolts) and the transaxle housing (6 bolts), and pry it off to access all the connecting rods. The only specialized equipment needed will be at this stage—a 12-point 10 mm socket ($5) to remove the rod bearing caps. To transfer the old piston to the new rod, just heat it in water over a stove to 80-90 °C until the pin can be pushed out with a wooden dowel and hammer. Heat again, push the pin in through the new rod, and put the retaining rings back. While reinstalling the piston assembly, use a piston ring compressor rented from an auto parts store ($0).
Depending on previous oil consumption it might be worthwhile to replace all 4 pistons and rings, with the 2015 model year part numbers. AFAIK you have to do both; revised rings don’t fit the old pistons. So unbolting the mid-seam of the block and it’s connection to the transaxle, you access the full length of the crankshaft. And the top half of the block is still stable? You’ve got the head off too?
Before you start the heart-hung transplant, double check the fuel. The Heet DEFINATELY won't hurt. LOTA gas stories in the news in the last two weeks. Usually a rod gets bent AFTER the the lubrication and coolant systems start swapping fluids and the engine makes a milkshake in the oil sump. My finely honed Spidey senses are telling me that this might not be the G3 Death Rattle....even though the fact that the misfire is still present even after the plugs/coil packs were changed is somewhat troubling. Keep us....posted. Good Luck!
With the head and the crankcase off, the remainder of the block was still stable. Working in my apartment parking lot with minimal equipment I didn't have the opportunity to pull the entire engine, so I removed only the minimum necessary.
