Cold engine shack issues

Sounds like they are guessing. You might ask them "exactly" how they checked the head gasket. Compression, misfire codes, coolant low, leakdown test, combustion leak test? Any misfire can cause the rattling but very few causes are responsible for an occasional "cold start only" shake. Plus they have already changed your plugs, coils, injectors, intake and egr.

The parts cannon has been fired but the enemy was flanking from the right. Watch the coolant level carefully. Many don't see any level change until it gets serious.

 

At this point its more about proving its not a head gasket leaking small quantities of coolant when the engine is cold and the bad cylinder is in a conducive position. If it is a head gasket it may run ok for months.

You will hear lots of opinions and stories like I cleaned my intake or egr cooler and it went away.

 

Did they change the EGR cooler as well? B/c changing out the manifold, EGR pipe and valve won't be effective if the cooler is still clogged.

 

Haven’t heard of a “shack” issue on a car before.

 

This. The dealerships are purely “mailing it in”. Check your invoices, but I’d suspect they replaced Exhaust Gas Recirculation valve but not the cooler, the roughly foot long component between the valve and intake manifold. Here’s a recent pic from a PriusChat member, what the cooler interior looked like:



Did the intake manifold and egr valve replacement cost you, or covered under the TSB for egr clogging. FWIW, both those items are easily cleanable.

a clogging egr will (allegedly ) cause the engine to run hotter, and (allegedly ) hasten head gasket failure, which often allows coolant into combustion chamber, which causes shaking on start up, can break the springs on the damper/clutch gizmo between engine and transaxle, bend piston arms and eventually destroy bearings and put holes through the block wall.

More info:

Bad Flywheel | PriusChat

 

I want a recount and will not be showing up to court at anytime later either.

 

I suspect "Voter/Fraud" .......

 

If you're not mechanically inclined you could get a cooler from eBay or a local junk yard, clean it yourself, and have a trusted local mechanic swap them.

 

Yeah, and it's no guarantee to fix either. I feel like I've read from others that their cold start shakes went away after cleaning the cooler, though if your head gasket is currently OK it might be helpful in prolonging the life of it anyway.

 

For the Exhaust Gas Recirculation system to function properly it needs to be clear from beginning to end: the connection at exhaust through to the engine intake ports.

 

The egr valve is closed at startup and low speeds. As a result a clogged egr cooler is not likely to be a realtime cause of cold start shakes, but it "could" be a root cause of a head gasket leak.

Even if you eventually change the head gasket or wait long enough where its engine replacement time, the egr cooler needs to be cleaned or replaced. So that effort now is only wasting some redundant labor.

Once a head gasket leak is confirmed, there is only a hail mary use of a coolant block seal. That might backfire with a clogged heater core and radiator. Reports from internet users usually suggest a block seal will almost instantly seal a slow gen3 leak and can last three to six months.

Shock and Awe

 

Looks dirty.

Did you take the egr cooler out and investigate it?

It also looks like several of the egr ports on the intake manifold are restricted, so were those rodded out?

Good luck and keep us posted.

 

Yes, Exhaust Gas Recirculation passages 1 and 2 there (small passages around 6 o’clock on each port) look especially carbon bunged.

When head gaskets let go, it’s usually cylinder 1 (leftmost as you stand at front bumper) that’s first to fail, start leaking coolant.




For 116k miles that’s pretty bad. The odometer number 100k has been tossed around, as opportune time to “get around” to cleaning; maybe sooner would be wiser?

Also, @Blurredforlife, you lived up to your namesake with that last pic? And thanks for the pics, seriously, this all adds to the data.