1JZ spitting fuel out exhaust and blowing smoke

[Jabtronic]

Hopefully this is the final problem I'm having with the 1JZ in my Cressida...
It now idles and runs fine (aside from running a bit rough when cold, and having a slight miss). BUT it's spitting fuel/oil out the exhaust and blowing a bit of blue smoke on idle. To me it seems to be running really rich, it smells like it anyway.

So far in my troubles I have:
Replaced ECU capacitors
Replaced coilpacks with 6 individual Bosch coils and leads
Replaced spark plugs
Cleaned ISCV out with Electrical contact cleaner (but mine is a fixed unit, apparently some 1JZ's have the ISCV with the screws so it can be disassembled?)
Cleaned throttle body (was pretty dirty, I noticed a difference in idle and reponse afterwards)

What else can I try?
I want to check and adjust the TPS, but can't find the correct procedure.. Do I need a feeler gauge?
Also, if I recall right, nothing happens when I unplug the ISCV while the engine is running... don't think thats normal?
Anything else?

[oldcorollas]

is this when engine is hot or cold?

when cold it will run rich, as well as spitting oily water out which is condensing in the exhaust...

[Screamn_Sleeka]

Are you sure its fuel? collect a small amount of the liquid and see if its flammable.
Its probably just water cause you have a custom exhaust with no muffler?

[Jabtronic]

Hmm.. well it's more noticable when cold.. I'll have to double check when it's warm actually. But I don't think it's condensation cause for example I drove the car around for a bit today and it warmed up to operating temp, then when I started it about 2 hours later it still sprays stuff all over the floor.

If there is anything behind the car it gets covered in the soot.

I'll see next time if it's flammable And yes at the moment it's basically running a straight through 3" exhaust. (No cat, staight through muffler)

[jeffro ra28]

MOST cars spit condensation/ black coloured residue from exaust on cold start up.

My garage door is a fine example

[oldcorollas]

Hmm.. well it's more noticable when cold.. I'll have to double check when it's warm actually. But I don't think it's condensation cause for example I drove the car around for a bit today and it warmed up to operating temp, then when I started it about 2 hours later it still sprays stuff all over the floor.
If there is anything behind the car it gets covered in the soot.
I'll see next time if it's flammable And yes at the moment it's basically running a straight through 3" exhaust. (No cat, staight through muffler)

2hrs is long enough for water to condense in exhaust, and for it to be cold enough to condense new water from new exhaust.

if it was running rich with no cat, or if it was badly missing, then maybe fuel could be being thrown out exhaust...

which is part of the reason for having cats

perhaps if you put a cat back in, you'll stop covering shit in soot, as the cat burns the soot....
who woulda thunk

but you should still investigate why it is running pig rich..
your oil smoke could be from anything... leaking turbo, rings, vlave stem seals... just apply the usual tests to try and determine

[131OWN]

Are you running a standard ecu? do you have a piggyback? If you running a OEM 1j computer make sure you 02 sensor is hooked up and working. If it is not it will run around 15percent richer and with no cat you will see unburnt fuel comming out the back.

[Jabtronic]

Yeah it's standard ecu, might try another o2 sensor and see if that helps. I'll also be fitting my metal cat soon so that should hopefully do something. The engine is missing a bit at idle so that's probably the main thing I should be concerned about, but it's nothing too major so I'll just put it all aside for now and worry about it down the track once a proper exhaust is on etc. I might get a hold of a timing light too and check that out.

[131OWN]

1JZ TPS settings are, with the throttle plate 100% CLOSED the TPS wire should be read approx. 0.55volts and at 100% OPEN 3.85 volts. Hope this helps

[JZA70 R]

if it was running rich with no cat, or if it was badly missing, then maybe fuel could be being thrown out exhaust...

which is part of the reason for having cats

perhaps if you put a cat back in, you'll stop covering shit in soot, as the cat burns the soot....
who woulda thunk

as far as i knew a catalytic converter is most efficient at converting gasses when the gasses are as close to stoichemetric as possible. this is why you have an oxygen sensor, so it can give your ecu the correct information for it to run a stoich air fuel ratio at idle and cruise. hence a cat is next to useless with rich air fuel ratio's.

the only reason i can think a cat will stop unburnt fuel from exiting the exhaust is by physically blocking it (think a brick wall), not because its burning it or converting it before it exits the tailpipe.

a cat is not a magical solution for a rich running engine.

and the tps voltages above are spot on.

[oldcorollas]

no, a cat will assist particularly when you are missing, which means there is excess fuel AND air in the exhaust, but this can lead to very high cat temps and possible damage to the ceramic support structure (part of the reason metal cats are not so good..)

when the cat is hot, unburnt fuel will quite possibly be broken down to form solid carbon (like.. carburising ), and then that carbon that has been deposited on the core of the cat will burn off when there is more oxygen
of course if you have rich mixutre all the time, or much of the time, then your cat gets clogged, or it ends up melting... as you probably are aware of...

the cat is a device with large surface area, high temps (say.. 400-600) and catalysts... fuel is not stable in those conditions and will break down to form carbon.

cat is not magical at all but it helps to understand how they work from a chemical point of view. (but hey, i might be wrong.. it is early after all )

[petergoudie]

If you have a 3" exhaust all the way there is probably no back pressure. It's just filling up with condensate. The 1jz is a small motor and the exhaust is probably too big. Even 14 litre kenworths might only have a 3" exhaust.

[131OWN]

Alot of Kenworths have twin 5" exhaust aswell

[SL666]

Mine sprays out the exhaust.. always has.. my base fuel pressure might be a bit high.. which might contribute, but I can't say i've ever worried about it too much.. ive just got a black spot in the drive..

Its much worse in winter when its cold - re the condensation theory

[Kedderz]

the 1g is pig rich from factory also, so i get the lovely black spitting of doom on start up also, especially now its fucking cold here in the morning.
As long as it goes away when the engine warms up your fine.