[Code of Federal Regulations]
[Title 40, Volume 30]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1051.305]

[Page 621-622]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1051_CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND VEHICLES
--Table of Contents
 
                Subpart D_Testing Production-line Engines
 
Sec. 1051.305  How must I prepare and test my production-line vehicles or 
engines?

    (a) Test procedures. Test your production-line vehicles or engines 
using the applicable testing procedures in subpart F of this part to 
show you meet the emission standards in subpart B of this part.
    (b) Modifying a test vehicle or engine. Once a vehicle or engine is 
selected for testing (see Sec. 1051.310), you may adjust, repair, 
prepare, or modify it or check its emissions only if one of the 
following is true:
    (1) You document the need for doing so in your procedures for 
assembling and inspecting all your production vehicles or engines and 
make the action routine for all the vehicles or engines in the engine 
family.
    (2) This subpart otherwise specifically allows your action.
    (3) We approve your action in advance.
    (c) Malfunction. If a vehicle or engine malfunction prevents further 
emission testing, ask us to approve your decision to either repair it or 
delete it from the test sequence.
    (d) Setting adjustable parameters. Before any test, we may adjust or 
require you to adjust any adjustable parameter to any setting within its 
physically adjustable range.
    (1) We may adjust idle speed outside the physically adjustable range 
as needed only until the vehicle or engine has stabilized emission 
levels (see paragraph (e) of this section). We may ask you for 
information needed to establish an alternate minimum idle speed.
    (2) We may make or specify adjustments within the physically 
adjustable range by considering their effect on emission levels, as well 
as how likely it is someone will make such an adjustment with in-use 
vehicles.
    (3) We may adjust the air-fuel ratio within the adjustable range 
specified in Sec. 1051.115(d).
    (e) Stabilizing emission levels. Before you test production-line 
vehicles or engines, you may operate the vehicle or engine to stabilize 
the emission levels. Using good engineering judgment, operate your 
vehicles or engines in a way that represents the way they will be used. 
You may operate each vehicle or engine for no more than the greater of 
two periods:
    (1) 50 hours.
    (2) The number of hours you operated the emission-data vehicle used 
for certifying the engine family (see 40 CFR part 1065, subpart E, or 
the applicable regulations governing how you should prepare your test 
vehicle or engine).
    (f) Damage during shipment. If shipping a vehicle or engine to a 
remote facility for production-line testing makes necessary an 
adjustment or repair, you must wait until after the after the initial 
emission test to do this work. We may waive this requirement if the test 
would be impossible or unsafe, or if it would permanently damage the 
vehicle or engine. Report to us, in your written report under Sec. 
1051.345, all adjustments or repairs you make on test vehicles or 
engines before each test.

[[Page 622]]

    (g) Retesting after invalid tests. You may retest a vehicle or 
engine if you determine an emission test is invalid. Explain in your 
written report reasons for invalidating any test and the emission 
results from all tests. If you retest a vehicle or engine, you may ask 
us to substitute results of the new tests for the original ones. You 
must ask us within ten days of testing. We will generally answer within 
ten days after we receive your information.