GM Service Manual Online
For 1990-2009 cars only

ALTITUDE EMISSION REQUIREMENTS AVAILABILITY AND ADJUSTMENTS

Federal emissions regulations applicable to 1983 model year vehicles contain requirements for vehicles sold for principal use in designated high altitude areas. (See list of designated high altitude areas on last page of this bulletin.) These vehicles must conform to high altitude emissions requirements.

In addition, there are regulations which require manufacturers to provide recommended in-use adjustments to improve performance, when applicable, for vehicles that change principal use after sale from either low to high, or high to low, altitudes.

This bulletin is intended as a guide for determining which vehicles may be legally sold for principal use at high altitude, which vehicles can and must be modified prior to sale if sold for principal use at high altitudes, and which vehicles may be modified after sale for improved performance when principal use is changed from high to low, or low to high, altitudes.

It is critical that vehicles be delivered to the customer with the proper emission system configuration to ensure compliance with applicable emissions regulations and to provide maximum customer satisfaction. Pontiac offers two (2) Federal altitude emissions packages as the following sales codes:

NA5 - Designed for all altitude use when NA6 is not available or low altitude only when NA6 is available.

NA6 - Designed for high altitude use.

Some Pontiac vehicles may be converted from one of these certified configurations to another using this bulletin as a guide. Gasoline engine configurations not shown in this bulletin do not require any modification.

VEHICLE EMISSION INFORMATION UPDATE LABELS

One of the labels identified by part number (shown on the following page) must be affixed to the vehicle whenever a vehicle is adjusted and/or modified using this bulletin.

The label should be ordered as regular parts and accessories through the Warehousing and Distribution Division of General Motors system. When ordering these labels via rapid entry, use order type CSD. Orders also may be placed on a PC66 and mailed directly to WDDGM, 6060 West Bristol Road, Flint, Michigan 48554, attention Ship Direct Department.

The label should be affixed in a readily visible position in the engine compartment and where possible beside the existing Emission Control Information (Tune-Up) label and should not be affixed to any equipment that can be easily detached from the vehicle.

Prior to installation of this label, the dealer code number and date of modification must be typed (with or without ribbon) or lettered with a ballpoint pen in the space provided.

PART NUMBER 14042590

Low altitude vehicle converted for operation at high altitude prior to sale.

PART NUMBER 14057201

Low altitude in-use vehicle modified for improved performance at high altitude.

PART NUMBER 14055121

High altitude vehicle modified for improved performance at low altitude. (This label applies to in-use as well as prior to sale.)

PRIOR-TO-SALE ADJUSTMENTS VS. IN-USE ADJUSTMENTS

Altitude adjustments on new vehicles prior to delivery to the customer for conformance to high altitude emissions standards are referred to in this bulletin as Prior-To-Sale Adjustments. Altitude adjustments on in-use vehicles for improved performance when there is a change of principal use from high altitude to low altitude or from low altitude to high altitude are referred to as Altitude Performance Adjustments.

The "altitude status" of a particular vehicle may be verified by the Vehicle Emission Control Information (Tune-Up) label. (See Figure 1 on the following page for label interpretations.)

LOW ALTITUDE VEHICLES WHICH MUST BE MODIFIED PRIOR TO SALE FOR CONFORMANCE TO HIGH ALTITUDE EMISSIONS STANDARDS*

Carline Engine Transmission High Altitude Use "T" 1000 1.6L (L17) All Install jumper wire from circuit #450E at ALDL connector to pin #18 on ECM connector.

*The above modifications which must be made prior to sale for conformance to high altitude emissions standards are the same as the in-use modifications which are recommended for improved performance for vehicles that after sale, change their principal use from low altitude to high altitude areas.

HIGH ALTITUDE VEHICLES WHICH MAY BE MODIFIED FOR IMPROVED LOW ALTITUDE PERFORMANCE Field Modification For Carline Engine Transmission Low Altitude Use "T" 1000 1.6L (L17) All Remove circuit *450E from pin #18 on the ECM connector.

PROCEDURE FOR FABRICATING AND INSTALLING JUMPER WIRE

1. Attach a terminal (part number 12004610) to each end of a three (3) foot length of 16 or 18 gage wire.

2. Connect to pin *18 of the ECM.

3. Route wire along and in front of the dash panel.

4. Connect to ground terminal of the Assembly Line Diagnostic Link (ALDL).

HANDLING OF ALTITUDE ADJUSTMENT EXPENSE (PRIOR TO SALE)

Any required altitude modification on new vehicles prior to delivery to the customer for conformance to emission requirements in the area of principal use are the responsibility of the dealer.

IN-USE

Owners Who Move To High Altitude Counties - Dealers in high altitude areas should encourage owners who have moved to high altitude counties to have the Altitude Performance Adjustments performed on their vehicles as outlined in this bulletin. These modifications are considered an owner maintenance expense.

Owners Who Move From High Altitude Counties - Dealers should advise owners moving to low altitude areas that they should have the Altitude Performance Adjustments performed on their vehicles as outlined in this bulletin. These modifications are considered an owner maintenance expense.

DESIGNATED HIGH-ALTITUDE LOCATIONS(COUNTIES)

ARIZONA Kit Carson Caribou Douglas Santa Fe Salt Lake Apache Lake Cassia Elko Sierra San Juan Cochise La Plata Clark Esmeralda Socorro Sanpete Coconino Larimer Custer Eureka Taos Sevier Navajo Las Animas Franklin Humboldt Torrance Summit Yavapai Lincoln Fremont Lander Union Tooele Mesa Jefferson Lincoln Valencia Uintah COLORADO Mineral Lemhi Lyon Utah Adams Moffat Madison Mineral OREGON Wasatch Alamosa Montezuma Minidoka Nye Harney Wayne Arapahoe Montrose Oneida Pershing Klamath Weber Archuleta Morgan Power Storey Lake Boulder Otero Teton Washoe WYOMING Chaffee Ouray Valley White Pine TEXAS Albany Cheyenne Park Jeff Davis Campbell Clear Creek Pitkin MONTANA NEW MEXICO Hudspeth Carbon Conejos Pueblo Beaverhead Bernalillo Parmer Converse Costilla Rio Blanco Deer Lodge Catron Fremont Crowley Rio Grande Gallatin Colfax UTAH Goshen Custer Routt Jefferson Curry Beaver Hot Springs Delta Saguache Judith Basin De Baca Box Elder Johnson Denver San Juan Powell Grant Cache Laramie Dolores San Miguel Madison Guadalupe Carbon Lincoln Douglas Summit Meagher Harding Daggett Natrona Eagle Teller Park Hidalgo Davis Niobrara Elbert Washington Silver Bow Lincoln Duchesne Park El Paso Weld Wheatland Los Alamos Emery Platte Fremont Luna Garfield Sublette Garfield IDAHO NEBRASKA McKinley Grand Sweetwater Gilpin Bannock Banner Otero Iron Teton Grand Bear Lake Cheyenne Mora Juab Uinta Gunnison Bingham Kimball Rio Arriba Kane Washakie Hinsdale Blaine Sioux Roosevelt Millard Weston Huerfano Bonneville Sandoval Morgan Jackson Butte NEVADA San Juan Piute Jefferson Camas Carson City San Miguel Rich


Object Number: 75367  Size: FS


Object Number: 74832  Size: FS

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.