The nation's second-largest oil company, Mobil Corp., reported a 131 percent year-to-year increase in third-quarter profits yesterday, topping the 118 percent gain announced Monday by Exxon Corp., the largest oil company.

And Standard Oil Co. of Ohio, the 14th largest producer, weighed in with an even larger increase -- 191 percent -- yesterday.

Tenth-ranked Sun Co. said its profits rose 65 percent in the quarter. Cities Service Co. was up 64 percent and Marathon Oil Co. reported a 58 percent gain. Cities Service and Marathon are virtually tied for 17th among U.S. oil companies.

Industry officials say that Mobil, Exxon and their two companions among the four largest American oil companies -- Texaco Inc. and Standard Oil Co. of California -- have a profit advantage over their competitors.

They said this advantage comes from the four companies' partnership in the Arabian-American Oil Co., which runs Saudi Arabian oil fields. Saudi Arabian crude oil costs these companies less than the oil that other companies must purchase from other members of the Organization of Petroleum Exporting Countries.

Meanwhile Chevron, the nation's 7th largest gasoline marketer, said today it was lowering its wholesale prices for gasoline, diesel fuel and home-heating oil by 3 cents a gallon.

Oil analysts said the Chevron move, which takes effect Thursday, marked the oil industry's first reduction in gasoline prices this year.

In Washington, the House apparently upset by the huge profits, being said the profits were "a disgrace to the nation. . . an absolute and utter disgrace."

Mobil said its profits in the third quarter were $595 million ($2.80 a share) compared with $252 million ($1.22) in last year's third quarter. Sales rose from $9.2 billion to $12.1 billion.

Mobil had nine-month profits of $1.44 billion ($6.77), up 81 percent from $792 million ($3.74) last year. Sales rose to $33.2 billion from $26.7 billion.

Sohio said its profits rose 191 percent in the third quarter, from $125.7 million ($1.06 a share) to $366.2 million ($3.03). The increase was the largest so far reported by a major oil company. The firm said sales rose in the quarter from $1.3 billion to $2.1 billion.

Sun said its profits in the third quarter were $174.3 million ($3.19 a share), up from $105.4 million ($1.97) last year. Sales rose to $2.61 billion from $1.83 billion.

Cities Service said its third-quarter profits rose from $52.6 million ($1.91) a share last year to $86.1 million ($3.11). Sales rose from $1.14 billion to $1.6 billion.

Marathon said third-quarter profits rose from $50.5 million (83 cents) in the third quarter last year to $79.7 million ($1.31). Sales were $1.91 billion in the third quarter, up from $1.2 billion in the period last year.

Results for the companies for the first nine months of the year:

Sohio said its profits rose 157 percent from $285.7 million ($2.59) to $735.1 million ($6.10). The firm said sales rose from $3.7 billion to $5.6 billion. Higher prices for Alaskan oil and greater production from the state, where Sohio is the largest operator, were the main reasons for the the earnings increased, Sohio said.

Sun said its profits were $453.1 million ($8.36), up 58 percent from $290.8 million ($5.44) last year. Sales rose to $7.49 billion from $5.48 billion. The company attributed the improved quarterly and year-to-date results to higher profits overseas and in the firm's Canadian unit, Suncor.

Cities Service said its profits rose 63 percent from $148.3 million ($5.36) to $241.3 million ($8.71). Sales rose from $3.43 billion to $4.47 billion. The company said increases in domestic oil and gas prices and copper prices contributed to higher earnings in all of its operating divisions.

Marathon said its net income rose to $269 million ($4.44) from $151.3 million ($2.50), a 78 percent increase. Sales rose from $3.6 billion to $5 billion. Marathon said higher volumes ad prices of oil and gas sales overseas "were the significant factor" to the better results for both the quarter and nine-month period.