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Can I get into trouble if I disconnect any of the
emission controls on my engine?

Yes, if you get caught. No, if you don't. But if you live in an
area that requires periodic emissions testing, you probably
won't get past an emissions check with missing or
disconnected emission controls.

WARNING: Federal law makes it illegal for ANYONE to tamper
with, disconnect, remove or otherwise render inoperative ANY
emissions-related control device. The Environmental
Protection Agency and most states have actually been rather
lax about enforcing this rule on motorists, but they haven't
hesitated to nail professional service facilities that have been
guilty of tampering. Even so, the fines can be hefty. A violation
may make you liable for up to a $2,500 fine!

No Tampering

The federal anti-tampering law does not, however, apply to
race cars that are not operated on the street, other full-time
off-road vehicles, show cars that are not street driven, or
vehicles not factory equipped with emission controls (most
1967 and earlier vehicles). So that exempts all antique cars,
and most classic cars and muscle cars.

Revisions to the Clean Air Act in 1990 further broadened the
definition of emissions tampering to include virtually ANY type
of engine or exhaust system modification that alters what
comes out the tailpipe. That means any nonstock aftermarket
part that is installed on your engine must be EPA-approved
and emissions legal (except on the exempt vehicles previously
noted).

Before the law was revised in 1990, it was only illegal for
professional mechanics to remove or disconnect emission
control devices. There was nothing to prevent a motorist from
tampering with their own vehicles. That loophole has since
been plugged.

What Is Emissions-legal?

Any of the following may be considered emissions tampering
and get you into trouble:
•        Removing the EGR valve or plugging its vacuum lines
•        Removing or disconnecting the PCV valve
•        Removing the stock air cleaner and heat riser duct
plumbing
•        Removing the catalytic converter
•        Removing or disconnecting the air pump
•        Removing or modifying the stock distributor vacuum
advance/retard
•        Altering the stock ignition advance mechanism or timing
curve
•        Replacing the stock distributor with an aftermarket unit
that is not emissions certified
•        Modifying, removing or replacing the stock computer or
PROM chip with a non-certified component
•        Blocking the heat riser duct under the intake manifold
•        Knocking out the filler restrictor on the fuel tank inlet
pipe
•        Replacing the stock non-vented gas cap with a vented
cap
•        Removing or disconnecting the fuel vapor recovery
canister
•        Changing the idle mixture or stock carburetor jetting
•        Removing or modifying the carburetor choke
•        Modifying or replacing the carburetor accelerator pump
with non-certified components
•        Installing an intake manifold or racing manifold that
lacks provisions for the stock EGR valve and/or a heat riser
duct
•        Installing a carburetor that lacks the stock emission
hookups
•        Installing non-certified fuel injectors
•        Installing a long duration "racing" cam that is not
emissions-certified
•        Installing exhaust headers that lack provisions for a heat
riser valve, an air cleaner preheat stove or fittings for an
oxygen sensor (if required)
•        Installing valve covers with open breathers or no fittings
for a PCV valve
•        Installing any induction, fuel or ignition system
component that is NOT emissions legal

Aftermarket parts manufacturers who make nonstock
performance parts for engines, the fuel, ignition or exhaust
systems must apply for special certification for any parts they
want to sell as being emissions-legal. The California Air
Resources Board (CARB) has been the leading government
body in this respect, so most submit their proposals to CARB.

First, they must submit detailed proof in the form of laboratory
dyno test that document their part does not have an adverse
effect on exhaust emissions. These tests are very expensive
and must conform with specified test procedures. CARB then
reviews the data and may or may not ask for additional
information and/or testing. If the product meets CARB's
criteria, CARB issues an "executive order" (EO) number (also
called an "exemption" number) certifying that the part is in
compliance with the applicable clean air rules.

An EO number means the component can be legally
manufactured, distributed, sold and installed on a street driven
vehicle in the state of California. It also means the component
is legally acceptable in all 50 states because the federal
Environmental Protection Agency also recognizes the CARB
exemption program as meeting their "Memorandum 1A"
requirements for certifying emissions legal parts.

Buying Emissions-legal Parts

Virtually all stock replacement parts are emissions-legal
regardless of who makes them. But if you're buying any
nonstock performance parts, heed the following to make sure
you're "safe" from an emissions standpoint:

* Look for wording on the box that says the product is
emissions legal or emissions certified for street use in
compliance with the EPA and/or CARB rules.

* Look for the EO (executive order) exemption number issued
by the California Air Resources Board on the box, product or in
the catalog. Remember, the product must have an EO number
to be street legal.

* If there is no EO number and one is required to be street-
legal, it cannot be legally installed on a street-driven vehicle.
Period.
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