Prius shakes cause? Clogged EGR or something worse

Has it been running low on coolant?

 

If it's the egr you have a sticking open egr valve. Normally it is closed at low rpms and wide open throttle. Toyota has a revised egr valve and ecu software.

Newer EGR Valve
Egr valve updated Kit 04004-58137
With 25620-37120 Updated egr valve


Blocking the egr flow is the definitive and easy test for an egr valve sticking open.

The reality is egrs don't cause a massive metallic sounding rattle. Even without obvious coolant loss because it only takes a few drops. So if the egr block test shows no improvement, move on to a cylinder borescope test.

 

Most common problem with Gen 3 engine shaking/start of engine failure is coolant loss due to head gasket failure between cylinder #1 & #2... If you have no coolant loss, I'd recommend focusing on examining/replacing vacuum hoses, which may have failed.

Can you please elaborate on oil loss issues? How many miles for each quart of oil lost? Gen3 used high MPG piston rings that wear out prematurely, but I've never read that related to engine shaking.

 

Presumably first cleaning? Way too late, almost certainty the head gasket is letting go, leaking coolant into combustion chambers. Confirm with borescope inspection.

 

Concur.
A clogged EGR is the equivalent to high cholesterol.
The 'death rattle' is, in many cases the resulting heart attack.

A 'minor' heart attack....isn't.

 

Just from what I’ve seen, every 50k miles would be the longest I’d stretch it. Your runaway oil consumption is not helping, likely accelerating the carbon build-up.

 

The runaway oil consumption is the reason for actual egr codes and clogging. It can also cause the egr valve to stick.

There is no harm in checking off the egr valve using the egr block flow test. Egr sticking or egr cooler clogging will code quickly since the system is checked almost every drive cycle. The symptom of egr sticking open is a stumbling not quite smooth engine. No loud noises or shaking. A clogged egr cooler has no symptom other than a code. However your video falls into the "massive metallic sounding rattle" category (damper slipping because of misfires).

It's time to carefully evaluate the car. Has the brake booster/master cylinder failed yet? Are there catalytic converter efficiency codes? Has the hv battery coded or shown fast charge discharge cycles or forces the engine to run at stoplights most of the time? One or two of these are expensive and combined with the engine might justify getting rid of the car.

The good news with other common concerns still good: A properly rebuilt engine can restore the powertrain to like new condition for the next 200k miles. You buy and swap in a a rebuilt engine - not yours. Think of it - no leaks, no oil consumption, no start up rattles or stop light rattles. Like almost new buyer enjoyed for the first 8 years or 150k miles when hybrids pay dividends.

 

Mine didn't get that memo.

For the oil consumption, the attached TSB's, while not applicable due to miles, has useful info. Also, last link in my signature is the full engine section.

This video (multi-part) video, brought to my attention by @rjparker, outlines a piston/ring replacment.

[

(I think part one is removal, hard to find.)

 

You had egr codes? Be honest.

 

Of course not. If you wait around for P0401 and cold-start shakes, you're screwed.

 

P0401 is not really a precursor to head gaskets or you would see that cause and effect on Corollas and gen4s. Gen3 oil burners do code quickly which is why Toyota had a campaign and an updated egr part. Certainly excessive oil burning has hg ramifications starting with preignition (pinging) caused by carbon buildup.

 

I suppose you can see it that way. My take:
I'm informing OP that EGR cleaning was too late, another cleaning won't "reverse" what's happening, and to concentrate on head gasket assesment.

 

For 5k i would just take the loss. Buy a new car. These are cheap cars on facebook marketplace. One thing to learn is keep the egr clean or delete it, and change the oil every 5k.

 

Sounds like it bent a connecting rod which happens on gen3 Prii with a serious hg leak.

The economy solution is a used in Japan JDM engine, maybe $1300 plus installation. However the other hybrid budget killers are still possibilities.

Don't buy another low cost hybrid. Real value and low cost of ownership is far more likely with a Corolla, Civic or Camry in your price range. Any shop can work on it, there are decent aftermarket parts and you still get decent mpg.

It's always a good idea to spend $200 with a trusted shop to check out any used car before buying.

If it's any consolation, your experience has been repeated hundreds of times on gen3 Prius engines. One shop near me has done a thousand replacements in the last four years.