Failed smog test fuel tank not holding vacum

Did they pressure test the cap itself? I'd check the donut too but when my son's was bad, it weeped fuel around it while driving. It looked moist around the tube and you could smell it a little.

1975 was the first year for cats in California. I took driver's training in the spring of 1975. Our high school's driver training cars were all new 1975 models from a local dealer and they used to fill them with leaded gas from tanks on campus back at the bus barn. What a mess that became and stink! My mom had a '75 Cutlass Supreme and my dad had a '76 Cutlass Supreme and both had cats. Brief interesting history lesson below.

As early as 1953, Los Angeles County Supervisor Kenneth Hahn inquired of Detroit automobile makers as to whether research was being conducted to eliminate emissions. The response was vague. With the threat of mandatory federal regulations, the auto industry began to install crankcase blowby devices (which returned unburned gases to the combustion chambers) on their cars. This was a significant advance because crankcase blowby produced 25 percent of the engine's hydrocarbon emissions. This equipment became mandatory on all cars sold in California beginning with the 1963 models.

This was only a start, since no effort was made to control exhaust emissions that were responsible for 55 percent of the hydrocarbons, most of the waste heat, and all of the carbon monoxide, nitrogen oxides, and lead emissions. Once again the industry balked, but in 1966 California required exhaust-control devices on all new cars. However, the 12 percent drop in hydrocarbon emissions and reduction in carbon monoxide experienced in Los Angeles between 1965 and 1968 was accompanied by a 28 percent rise in nitrogen oxides. By 1968, nitrogen dioxide, which is highly poisonous, exceeded the "adverse" level on 132 days. The serious increases in nitrogen oxides were due to the inability of available antiemissions technology to act on them, as well as to the increase in automobiles and rising gasoline consumption. A new technical fix was sought from the automobile industry and, in response, catalytic exhaust devices were developed to convert nitrogen oxides into harmless by-products. Catalytic converters were required on all 1975 cars sold in California. Leaded gasoline, however, played havoc with the catalysts. One solution was to use lead-free or unleaded gasoline. (Another was the unauthorized removal of the devices by motorists.) While non-leaded gas became available, the complete phase-out of leaded gasoline, as stated earlier, did not commence until 1986.