||Emission testing of 1974 Pontiac V-8 with defective thermal vacuum valves.
||Environmental Protection Agency, Ann Arbor, MI. Technology Assessment and Evaluation Branch.
|| Environmental Protection Agency, Office of Mobile Source Air Pollution Control, Emission Control Technology Division, Technology Assessment and Evaluation Branch,
Air--Pollution--United States. ;
Automobiles--Motors--Exhaust gas. ;
Air quality--Standards--United States. ;
Exhaust emissions ;
Air pollution control ;
Thermostatic valves ;
Fuel consumption ;
Pontiac automobiles ;
Motor vehicles(1974 models) ;
Air pollution control equipment
||NVFEL Library/Ann Arbor, MI
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||11 p. : ill., charts ; 28 cm.
The EPA became aware that there were problems with the Thermal Vacuum Valve (TVV) installed in 1974 Pontiac V-8's. To confirm the existence of the problem, functional tests were conducted on TVV's collected from in-service Pontiac vehicles. These tests consisted of applying a controlled vacuum to the valves while raising their temperature in a stepwise fashion and observing when they actuated. The majority of the valves tested failed to meet their design specifications. In order to quantify the effect of the failed valves on emissions, exhaust emissions tests were conducted with the TVV's installed in a 1974 Pontiac. However, only a limited test program was undertaken. This report describes the exhaust emission test program and presents the data and results. The conclusions drawn from these tests are necessarily of limited applicability. A complete evaluation of the degradation of the emission control system caused by defective TVVs on the 1974 Pontiac V-8's requires a much larger sample of test vehicles than is economically feasible in in-house test projects conducted by EPA.
Cover title. "June 1976." "EPA-AA-TAEB 76-21."