What are you trying to achieve?
Are you trying to destroy your engine?
Even as rugged as a Corolla is you may eventually succeed if you keep
throwing this crap in the crankcase.

Don
www.donsautomotive.com

Why do you need to flush it out? Regular oil changes should keep
everything in check. My advice would be to check for a high detergent
oil, as lightweight as possible. Run it for a short period, then
replace it with your regular engine oil.

Sometimes a flush can be a bad thing. I've seen where a flush results
in the removal of crap in the camshaft journals, ending up with no oil
pressure to the top end. True, the real problems was worm cam
bearings, but it sure was effective at making the engine completely
unusable without a good investment. Sometimes not worth it on an old
engine.

If your engine is sludgy, don't expect anything to clean it out
overnight.  Anything that *does* clean the engine out overnight is
probably not good for it.  I would recommend sticking with the Auto-RX
and using something like Shell Rotella for your rinse oil.

nate

Any of those "flushes" that are strong enough to remove
sludge quickly will break down the oil film barrier on the
bearings.  The best thing to do is use a higher detergent
oil as previously mentioned by another poster.  An oil
formulated for diesel engine application may help.  Keep in
mind that any of the solvent flushes can cause rather large
samples of sludge to become dislodged to clog oil passages
or get to bearings - it has to go somewhere before it gets
to the pan where you can drain it.  Over the years, I have
seen many engines pulled down for repair.  The ones with
regular oil and filter changes at intervals under 7000 miles
or so have rarely had much sludge buildup at all unless they
were operated most of the time in short distance driving.
It is almost impossible to prevent sludge buildup in engines
that are seldom run at normal operating temperatures because
the additives in oil work at normal engine operating temps.

Lugnut

dunno, but one precaution that should be exercised after a flush job on
a heavily sludged engine - is to drop the pan, and clean the oil pump
filter screen, they say.

Agreed with the others...engine flushing is NOT something you do for
regular maintenance, and trying to blast a neglected engine clean is
like playing Russian Roulette, except with one EMPTY chamber...when
that stuff moves, it's gonna cause a problem down the line...

You want something that will slowly clean an engine in manageable
increments? Do what was suggested above...Marvel Mystery oil works
well, I've heard 10-%15 ATF with an oil change works well, I only flush
as a last ditch attempt to see if an engine can be revived before
needing a complete teardown and inspection, and even then don't expect
much...had a couple through the shop that were so neglected they
stopped running due to low oil pressure cutoff, revived one or two by
running 25-30% Kerosene in coinjunction with new oil for 10 or 15
minutes, then change the oil again to loose the kerosene and flush any
remaining from the engine, then once more to remove any sludge or
traces of kero after a couple hundred miles...it works about as often
as it doesn't...kind of a crapshoot..

I bought a beater car awhile back, poorly maintained engine-wise.
Sludged up in the valve heads.  Used some Gunk 5-minute engine flush,
it cleared it out rather well, but the oil was really bad looking when
draining out, and got a short-term leak from rear crank seal.

But, it was old beater car, no real loss if the Gunk harmed the engine,
which it didn't, in this case.  I'd hesitate to substitute an engine
cleaner to fix lack of regular oil-changes [including new filter].