4AGE noise found...

[Gleno28]

kinda continuing from here...

Finally got the 4AGE to a doctor with the squeeling issue, they had a look (6 mechanics standing around the engine bay) and soon diagnosed the problem. It's getting excess vacuum in the block and sucking air through the rear main seal!

Has anybody come accross this before and what fixes are recomended? I'm thinking of reducing the size of the hose to the intake, or moving the vent to before the TB??

It's got a single vent off the intake side cover to TB (see pic), engine has been converted to RWD, bigport head, TVIS hooked up.



Any ideas,
thanks
Glen.

[2jzhilux]

pcv valve working????

[Gleno28]

sorry, updated pic.

pretty sure it's been removed during conversion by someone else

[2jzhilux]

if that is your problem (sucking air through the seals)i would get a pcv valve and put it inline with your breather hose
i dont like your chances of fixing it with this though
its probably your spigot bearing shit itself if the noise is coming from the rear main seal area

[Gleno28]

oh, forgot to mention the important bit of evidence... the noise goes away and sucks in air when you pull the dip stick while running!

[Matt-AE86]

dood, look at your plenum!

Its a cut and shut, there for the PVC valve is in the manifold and now is blocked off by a block off plate where the throttle body use to be OR where you have welded it up if so.

Sollution: Catch can. Vent it to air. OR JDM Intake with JDM throttle body (only this combo works)

Your crank case pressure isnt releasing thats why when you take dipstick out, all is good, in a way..

Dont plumb it back to intake. it will fail agian.

Good luck!

[30psi 4agte]

For starters Im led to believe That a 4age doesnt use a PCV "Positive crankcase ventilation" valve
So that theroy is out the window !

Matt i think you are confused ....... You are thinking of the idle air bypass port which is used to control idle speed. This will have nothing to do with crank case pressure.

You are however on the right track as far as setting up a catch can.

Glen : Try pulling the hose off that goes from the rocker cover to the inlet manifold. Block off the inlet manifold side and plumb th rockercover side to a can of some sort ..... This should help you out.

[roadsailing]

yeah i second that, piss of the plumbing from the crankcase to the inlet, just run a catch can.

if you must plumb it back to the inlet, make sure it is before the throttle, this is the stock setup even if it might niot look like it.

[Jorrs]

bugger catch can
go cheapo and stick a hose with a proper filter on the end will do the same thing, just not as legal. works for me !

so thats true that 4age doesnt have a PCV valve ? is that all 4age ? just thought i had one

[oldcorollas]

turbo... thats should increase the crankcase pressure a bit

[oldeskewltoy]

Hmmm you say just pulling the dip stick stops it??? the added volume of air past the dip stick is VERY small.... it shouldn't be your problem... I'd say check the intake cam cover... and breather hose... make sure there are no obstructions.

You also might want to perform a cylinder leakdown test and see if you just have tooo much blowby

[Mr Revhead]

if its sucking air in, it wont be blowby!

[rodi]

All motors should have a breather before the throttle body and after the air filter, you must have pcv valve between the manifold and rocker, better to run one than not

[Mr Revhead]

as mentioned above, 16v 4ages dont run PCV valves

[Gleno28]

Cheers for the quick replies guys! +reps

So, short of going for a catch can, simplest way would be to move crank vent to between filter and TB, reducing the constant vacuum within the crankcase?

Sounds like a plan. In terms of PCV, have people retrofitted PCV's in this kind of situation?

Cheers