Intake manifold cleaning necessary with revised part?

Might as well do it while cleaning the rest of the egr circuit, maybe every 50k

 

While I am not familiar with any revisions, in general, you never need to clean the intake manifold.

 

Wrong again jumbo

 

I wouldn’t say “never.” If the intake passages are restricted, they should be cleaned, wouldn’t you agree?

Some cars show a lot of clogging and others have little clogging. We’ve seen photos here on PriusChat which show really bad clogging. I don’t know why some clog more than others, but usually, If the EGR and pipe clogged up with oily goop, the intake manifold will also have this goop. If the EGR is dry and fairly clean, the intake manifold will probably be fairly clean as well.

 

Ah I was thinking of those individuals who keep 'cleaning' the fluid out of the intake manifold, which is just gasoline pumped back out of the cylinders, and always puddles there.

 

Actually... we think that goop is oil, not gasoline. And we think the cause of that oil is from the PCV, and it can be prevented by installing an oil catch can. This, in turn, keeps the valves clean and we think it will prevent the EGR from having the oily deposits which then clog the EGR cooler, EGR valve, and intake manifold.

These things are different but interrelated.

 

It's possible that the revised manifold does a better job of evenly distributing EGR gas between cylinders as the path clogs. But it still does clog because the root cause hasn't been fixed (see @Rebound post above). So nobody can say how often to clean it, but the general consensus is to aim to do your first cleaning around 100K miles, and every 50K after. If you do install an OCC it's expected that this will greatly reduce the amount of goop that clogs the EGR path.

Either way, if you get a rattle on startup that's a sign to get on it post haste.

 

There are 3 ways various substances get into the intake manifold: PCV, EGR, and spit-back from the ports.

Just clean it periodically, it's not that hard, and from then on you can set a reasonable interval. And chances are if you do some mod, say install an Oil Catch Can, that interval can be significantly longer. But verify: OCC's are far from 100% effective.

My algerbra's maybe out-to-lunch, but I would postulate: if you put two of your pick of OCC in series, the first collects x, the second collects x/2, then that style of OCC is 50% efficient?

If you watch video of transparent wall OCC in action, it's a miracle that they collect anything: stuff blows through there (and on to the intake manifold) very fast.

 

We scoped my cylinders at a meet up with a revised one on a refresh. “Does a better job” doesn’t even comes close to describe the distribution

 

I'm surprised you could tell any difference. You guys take pix?

I figured the two extra dirty cylinders on my 2010 were due to valve issues, never even thought to attribute it to those nasty EGR runners in the original IM. (I guess maybe both things could be true, with one the cause of the other.)

 

We took photos of each cylinder with raytheeagle’s scope, photos are posted twice on 2 different threads, can’t miss it with a easy short simple quick search on here.

 

I'm still not clear what the verdict was. Do you think the revised intake made a difference? I'm guessing it might make the pistons look more uniform?

Funny thing, if you look up the intake manifold, there's more part number supersessions than you can count on one hand.

 

I'll save folks the effort:

Possible Monthly install meets. Bay Area-Fremont

They'll also get to see @The Critic 's fine work with paint finish.

2 separate engines were bore scoped though for comparison.