Well, the cars I used to have were FWD GMs with 3800s, those cars never really cared what you did to them as long there was oil in them. I ran STP and seafoam in those cars and they lasted me a long time with hard work. Not sure about the Prius though. Mine has 180k miles and I scheduled an EGR cleaning and spark plug change next week. But I wanna know if seafoam/stp in crankcase helps the car? Since these had VVT-i, I don't wanna mess things up. Car currently gets 47.8 MPG combined with some Lyft work, and I feel that the engine is still ok.
Who's doing the EGR cleaning, what sort of place? How much? 180K is very late in the day for this, btw. Don't assume a belated cleaning will turn back the clock; cylinder one and two have likely been running hotter for the last 50K. Plug replacement now for any particular reason? How long have you had it btw?
Addendum: another case of too many threads on same subject; I'm out. 2010 Maintenance and MPG | PriusChat
I have used 4ounces of seafoam the last 4 oil changes. I used the new Valvoline "Restore" last oil change a few weeks ago, and changed to the 2nd one yesterday. I turned 335,000 miles this week. I usually drive 63-65mpg and used about a quart every 2500 miles. I've been driving 65-67mpg and used 1 quart in the same miles. In the past I would use 2 quarts. so it "seems" that it has done something for the good. I figured with other 300,000 miles, it couldn't hurt it much. If it keeps the engine going for longer, I'm happy!
So I haven't lurked around on this forum to know all the common problems with the 3rd gen but obviously seen enough posts about the EGR valve and some head gasket concerns. We are gonna be nearing 200 k with our 2011 Prius, engine still run great, decent power, good MPGs...we never got either done. What do you think likelihood is that she's still totally healthy and is it worth doing an egr cleaning at this point?
It's a good idea to clean the egr system, which includes the intake manifold. It's preventive maintainence. Like changing engine oil. Keep an eye on the engine coolant. See where it's at when the car is parked overnight, and checked it once a week or so. If it starts going down, check for leaks, but if you get a knocking noise when the engine starts sometimes, it's likely a leaking head gasket. DO NOT PUT ANY SEALER IN THE COOLANT!!! Then replace the head gasket, or have someone do it for you. The sooner you replace it, the less likely you'll have a warped head, or throw a rod through the block. From reading on Prius Chat, it seems the ones that do mostly highway driving go the longest, city driving go less mileage. If you can replace it yourself, you could always change it before it fails, then you won't have to worry about it.
We have zero coolant issues so I'm not worried about the head gasket for now but alright I will take out the intake + egr and see what we got. We have had about 50/50 with our highway/city driving for its life, average about 48 mpgs (way better than my 22 mpg for the GR Corolla lol)
