---
kind: "section"
citation: "40 C.F.R. § 1042.320"
title: "40"
number: "1042.320"
heading: "What happens if one of my production-line engines fails to meet emission standards?"
url: "https://uscodex.org/cfr/40/1042.320"
---

# §1042.320. What happens if one of my production-line engines fails to meet emission standards?

- (a) If you have a production-line engine with final deteriorated test results exceeding one or more emission standards (see [§ 1042.315(a)](/cfr/40/1042.315.md?p=a)), the certificate of conformity is automatically suspended for that failing engine. You must take the following actions before your certificate of conformity can cover that engine:
  - (1) **Correct the problem and retest the engine to show it complies with all emission standards.**
  - (2) Include the test results and describe the remedy for each engine in the written report required under [§ 1042.345](/cfr/40/1042.345.md).
- (b) You may request to amend the application for certification to raise the FEL of the entire engine family at this point (see [§ 1042.225](/cfr/40/1042.225.md)).
- (c) Use test data from a failing engine for the compliance demonstration under [§ 1042.315](/cfr/40/1042.315.md) as follows:
  - (1) Use the original, failing test results as described in [§ 1042.315](/cfr/40/1042.315.md), whether or not you modify the engine or destroy it. However, for catalyst-equipped engines, you may ask us to allow you to exclude an initial failed test if all the following are true:
    - (i) **The catalyst was in a green condition when tested initially.**
    - (ii) **The engine met all emission standards when retested after degreening the catalyst.**
    - (iii) No additional emission-related maintenance or repair was performed between the initial failed test and the subsequent passing test.
  - (2) Do not use test results from a modified engine as final test results under [§ 1042.315](/cfr/40/1042.315.md), unless you change your production process for all engines to match the adjustments you made to the failing engine. If you change production processes and use the test results from a modified engine, count the modified engine as the next engine in the sequence, rather than averaging the results with the testing that occurred before modifying the engine.

## Notes

### Amendments

[73 FR 37243, June 30, 2008, as amended at 75 FR 23004, Apr. 30, 2010; 88 FR 4662, Jan. 24, 2023]

### Authority

Authority: 42 U.S.C. 7401-7671q.

### Source

Source: 73 FR 37243, June 30, 2008, unless otherwise noted.

### Amendments

[73 FR 37243, June 30, 2008, as amended at 75 FR 23004, Apr. 30, 2010; 88 FR 4662, Jan. 24, 2023]