Thanks for everyone who provided info on maintenance for my 2014 prius with 110k. I got my EGR intake cleaned (mechanic said it was dirty but not too bad), spark plugs, inverter fluid and oil changed. Everything seemed to check ok according to my mechanic. One thing my mechanic mentioned was that a sign of a bad head gasket is a bad rattle (misfire) when starting the car which disappears after 15-20 seconds and then returns to normal. I told him I never experienced that and went on my way. So I started thinking about it, and remember about 4-5 months ago I had a rattle on start up, and feared my catalytic converter was stolen. But it went away and I long forgot about it and it hasn't happened ever since. I'm pretty sure it was a misfire but who knows. So my question is: Is a misfire (if it was one) always mean my head gasket is failing or can it be a few different things? Thanks!
no, not always. it can also mean the engine wasn't fully warmed up the last time it ran, and some water was sitting in the intake manifold. i wouldn't worry about it unless it became more consistent. good job on the egr!
Thanks good to know! Time to save up for the day I need to change the gasket, hybrid battery, etc. This car has been rock solid reliable. Want to keep it until the wheels fall off! Thanks!
other than those few weak points, they are great long lasting vehicles. and when those are replaced with updated parts, they'll last practically forever.
There's other reasons for brief rough running of atkinson engines... Earliest sign you'll get of it being a problem is a sucking sound when you take lid off coolant reservoir on passenger side. Also, most people that have it bad have alot more than 15-20 seconds of rough running.
Good point... We usually assume EGR cleaning is the valve, the cooler and the intake. But if you don't do all of them, you didn't do it right.
The description of the job on the receipt says: Remove EGR valve, pipe and cooler. Soak EGR cooler in carbon remover. Clean EGR cooler, egr valves and pipes. Reinstall on vehicle. I think I should be good. I think
How 'bout intake manifold? If not cleaned, FWIW, that's a relatively easy DIY. First link in my signature has some info, torque spec's for the manifold and throttle body in repair manual excerpts attached. No coolant lines need be disconnected from the throttle body btw, contrary to @nutzaboutbolt's video. Check with them, might be done, but if not: just use brake clean, brushes (small diameter one for the small EGR passages (one per intake port). Clean those ports out too, plus the injectors. Don't just wholesale spray brake cleaner in the ports. If you want to spray the injectors, stuff bits of shop towels further in first, spritz conservatively, then fish the towel bits out. Leave it clean/dry. Don't use oxy-clean or oven cleaner (caustic solutions) on the intake; there are corrosion prone inserts that'll react with it. Used brake cleaner (you should do this over a pan) can be poured over a small tray of kitty litter (clay clump style works well) and set in a sheltered, outside loc' to evaporate. Then bag the kitty litter and dispose with garbage.
