Getting set for smog test so paranoia lurks. Current set of Motorcraft
Platinum finewire AGSF32FM have only 15K on them and don't look too bad.
Is there a plug that is better or one that might enhance emission test
Perhaps a test only set? Engine in good shape for 190K (has always
passed) but burns about a quart of Motorcraft 10/30 synthetic blend
every 1100 miles or so.
TIA for any input.
I've been told many times that if there was a sparkplug that gave you lower
emissions and better mileage don't you think the manufacturer would use it?
As for the oil burning: on a car with 190,000 miles, I doubt using a quart
of oil every thousand miles is out of line. I certainly wouldn't go to a
heavier grade or use any additives to stop it. You might want to do a
compression check and/or a leakdown test to see what kind of shape the
cylinders, valves and rings are in, but personally, I wouldn't worry about
On emissions, it either passes or it doesn't, and a good mechanic can tell
you what the best time is to bring the car in for emissions..Often when the
car is warmed up and driven a little hard before bringing it in. Often it's
a faulty component that causes a car to flunk. I seriously doubt spark
plugs or a different oil will make a difference. Now, that said, if the car
is smoking you might be able to hide that, but I can't see a car that only
burns a quart every thousand miles smoking.
Forget changing the plugs - if it's not misfiring it won't gain you
anything. Put fresh oil in for the test - 10W40 or 15W50 will cut the
oil consumption to less than half - which will keep the hydrocarbons
down and keep the cat functioning (clean). And really, a yankee quart
every 1100 miles is NOT a serious oil consumption rate.
On 1/16/2011 11:38 AM, email@example.com wrote:
A few years back you helped me with changing the gasket on the oil
filter housing. I'm an old (as in no longer) boat racer and as soon as
it was time for an oil change (bought it new) I switched to a 20-50
racing oil. Seems to have worked out Ok but I always wondered if that
impacted the aforementioned gasket. Switching to the lighter oil upped
my mileage noticeably (to my surprise) but since I am 'paranoid' and it
is winter, I may go ahead and change to something heavier for a while.
OK - I have no idea where the OP is located, so if the weather is
terribly cold or not - and a 10W30 or 10W40 is the same thickness when
cold - but 10W40 will, all other things being equal, be consumed at a
As for the wear, it can actually balance out, depending on what
driving the car gets. Yes, thin oil (low number before the W)
lubricates quicker when cold - but in some cases thicker (higher
number after the W) oil lubricates better when warm, and the engine
spends a lot more time running at temperature than it does starting
with thickened oil.
And as a mechanic I don't buy the explanation the manufacturers are
giving for using 5W20 oils (better lubrication when cold). It is a
CAFE issue much more than an engine wear issue. The clearances in
engine bearings have not changed appreciably in over 35 years. The
improvements in quality control and finish quality means the mean
clearance may well have INCREASED as there are fewer high spots to
cause restricted clearance.
When a clearance was specified as 10 thousanths of an inch it was very
common to have a few percent of the bearing surface less than 5
thousanths of an inch - which caused (required) accellerated wear to
get "broken in". That does not happen on today's engines to any
If the OP is in a very cold part of the continent he might want to
consider a wide range synthetic oil (like a 5W50) to get both
When I had to go through that here in Florida I would purchase one of the
many gas additives that the autoparts stores sold that advertised to reduce
emissions. It would always help my 79 Corvette pass the tests, if I didnt'
use them I was doomed to failing the test. I don't know if they still sell
them as they stopped emission testing here years ago.
I would not worry about the plugs at that mileage unless
there is a misfire.
The only thing you may want to do is clean the MAF with a
good residue free aerosol electrical cleaner. Make sure the
air filter is not choked with a ton of visible crap.
The oil consumption on the 4.6L V8 is as often as not is
valve seal leakage with nothing to do with pistons, rings or
cylinders. 1qt/1100 miles is not excessive. IIRC, Ford
still specifies 1qt/750 miles or more as excessive on most
of their rngines. Keep in mind that a qt of oil every 1k
miles is something like 1 drop every 800 feet - really
miniscule. Most engines that appear to have zero
consumption are simply replacing consumed oil with
combustion byproducts (blowby).
Your best bet is to continue using the lighter 10w30 oil.
The 4.6L seems to not circulate the higher viscosity oil
well resulting in noisy timing chains and valves until fully
warm. Ford now recommends a 5w20 for pretty much all of
it's vehicles. I have stayed with 5w or 10w30 in all of
mine since they predate Ford's 5w20 recommendations. I have
a couple north of 1/4 mil miles with no oiling problems
other than valve seal replacement. The worst one on oil
consumption at 1qt/600 miles is very close to the low end of
the emissions requirements - about as clean as it was new.
The cats are not affected as much by oil consumption as they
were in the early years since oils have been reformulated to
remove components that are adverse to the cats longevity.
The best thing for the test is a fresh oil change followed
by a nice drive a normal temperatures just before plugin'
her in for the sniffer test. If it then fails, you can
examine the test results for clues to the guilty system or
components. There may also be stored fault codes. You may
want to visit one of the parts stores to besure there are no
stored codes. Here in GA, a stored fault code is an
automatic failure even if there is no light. They don't
take the time to determine the code is or is not related to
the emissions portion of the system.
Doing a manifold R&R to repair leak in heater pipe bracket mentioned in
earlier post and there was a noticeable oil residue around the intake
seal areas and inside the intake manifold. Can that be valve seals also?
Mechanics have ways of doing lots of things, but you absolutely have to do a
leak down test or something similar to determine where and what the problem
is before you do any work. IMHO I still don't think you have a serious
problem. Before you start freaking out do the simple things first, air
filter, warm up the car and blow out the crap, and see how it does on the
emissions test. Some mechanics can test emissions before you actually do
Your NO is a bit higher than I would have expected. It can
usually be corrected easily by cleaning the EGR ports on the
4.6L V8. You may want to do that before your next test if
you get a little slack time.
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