Used pre-facelift gen 3

It looks like you're not in the US and I don't see tons of reports from the EU on blown head gaskets so there may be something to that I don't know You don't mess with the head gasket till it's time somebody notices some seepage coolant disappearing rattling something I don't think this is the kind of engine where you would just do this as preventive maintenance because we know it's coming but I guess one could.

 

Im struggling to decipher those values; can you spell out in-full the units, and double check the values (in particular the 330 value)?

In general, any 3rd Gen Prius (2010~2015 model year) with over 100,000 miles (160,000 kilometres) is almost certain to be clogging up with carbon, and in danger of head gasket failure. My theory is the first condition causes the second.

You can find more information in the links in my signature; if viewing on a phone turn it landscape orientation to see signatures displayed.

 

You'd be lucky in the USA if anything was done about that. Point blank and no dealer I know of is going to be taking apart EGR intercoolers and all that nonsense unless something is broke and by the time something is broke you're replacing an engine or the reciprocating mass and putting it back together whatever it is you're doing and the Toyota dealer probably will call it a day and do nothing it'll get shoved off at auction or go to salvage You got to realize these cars are 10 years 13 14 whatever now they don't do anything with those generally they're just the loss

 

Off of the top of my head...Almost all of this is optional, except for the EGR. Some of this will be gratuitous, but I'm listing it here to be complete. Do whatever you want, don't do what you don't. This list is for a DIYer. I would think paying a shop for all of this would be excessive.

Use a scantool to get the CALID out of the ECU. Some of the other forums here list the ones that have the EGR updates.

Drain the old coolant - it makes servicing the EGR a little easier

Clean the EGR valve and cooler, intake manifold (EGR passages, and oil residue at the bottom). New gaskets for EGR valve, cooler, intake manifold, and throttle body.

Check out the coolant lines, vacuum lines, ventilation lines and replace any that are cracked.

Clean the throttle body, since it doesn't cost much and it's easy to get to at this point replace the PCV valve.

Clean the MAF sensor.

Replace the transaxle fluid, engine coolant, and spark plugs. Check the inverter coolant.

If you've got older firmware in the ECU, have it updated.

Pull the cover off of the HV battery intake and vacuum out the dust. If excessive, pull the panels off the battery and vacuum out the battery air passages and cooling fan.

Replace the cabin air filter (you're probably already up to date on this).

Since you'll have them off, Replace the plastic push clips that are loose or missing on the plastic underbody panels and fender liners.

Suck out the old brake fluid, add some new, and bleed the brakes. Jack the car up and wiggle the front wheels side to side looking for play in the wheel bearings and tie rod ends. Wiggle up and down to check out ball joint play and wheel bearings. Check the lower control arm bushings for excess wear. Do the same for the rear to check out the rear wheel bearings.

Look for worn-out struts. (Maybe just replace them anyway - my 2011 got a lot better handling when I did this at 125K. Front end alignment required when changing front end struts, maybe an alignment is due if you regularly hit speed bumps or drive over a curb at the end of your driveway.). Check your tires for uneven wear/cupping that could also indicate worn suspension components.

Check for excess rust on the other suspension and exhaust components (especially if you live in the rust belt).

Check for excess wear on the brake pads - don't replace them if you don't have much wear, or brake noises. If you never use the parking brake, maybe cycle it a few times. (Be forewarned, I've never had any issues on my Prius, but this caused a GM pickup to lock up the parking brakes on the rear because of the cable corrosion, forcing me to do a rear brake job).

 

No. They’re doing their best to sweep it under the proverbial rug.

All Gen 3 years have essentially the same EGR system. There was a revision to the EGR valve, and the intake manifold, but ineffectual. Optimum compensation for what’s essentially a design defect, would be to clean it every 50k miles.

In addition to all the above posted suggestions, when the wipers and cowl are off, it’s a good time to cover the cabin air intake securely, with galvanized steel anti-rodent mesh, the kind with 1/4” openings (readily available at hardware stores).

 

2010-12 Prius came with the older egr valve and software.

Newer EGR Valve

Egr valve updated 25620-37110
Kit. 04004-58137 With 25620-37120

Valve With Gaskets $154
04004-58137 - Toyota Parts Deal


Valve alone $290
25620-37120 - Toyota Parts Deal