EGR Issue back again?

One issue with professionals cleaning, you never know how thorough they are. Being paid by the hour, they will definitely want to rush, maybe cut corners.

According the document you posted, in January you were already experiencing knocking at start-up; that was the complaint that lead to EGR being cleaned. This is could be due to coolant in the combustion chamber, leaking past the head gasket.

It's my belief that carbon-clogged EGR components lead to head gasket failure. But cleaning the EGR components once the head gasket failure is started, will not turn back the clock.

That said, 95k kms is very early for head gasket failure.

 

Head gasket failure.

 

No; a head gasket itself is not expensive to buy, but replacing it is a significant engine disassembly chore whose cost will often need to be weighed against the value of the car.

It certainly isn't the kind of thing a person would leap into without being sure it is the issue.

There are some tests that can help rule that possibility in or out. And if the symptoms you're having are an engine running at fluctuating RPM and making some rattling sounds, there are other potential causes to check for as well.

 

no, please tell us about it

 

it is possible they didn't clean the 4 small intake manifold ports

 

do they know? most dealers here don't even know there's an egr problem, and toyota is not telling them

 

A couple of tests for head gasket integrity:

leak down test: cylinders are pressurized one at a time, at top dead centre of compression stroke, with special gauge set. How well they hold pressure, and where leakage occurred are checked

boroscope inspection of cylinders, while coolant system is pressurized. They look for coolant leakage into cylinders.

 

Easiest way to check is to open the cap on your coolant resevoir on passenger side of engine compartment. If you here a sucking sound when you do that you need to monitor coolant loss. This indicates headgasket failure and if you're only driving around town and avoid driving in hot weather you can go years avoiding this relatively expensive repair.

 

If it makes a noise when you open it, that's the problem... I've saved huge amounts of time doing diagnostics with this technique. Literally a few seconds after someone arrives with a problem Gen3 prius the diagnostic is done and we both get on with our life.

 

The usual way seems to be to register with YouTube (or other movie hosting website), upload your movie there, then link to it here.