A senior Democrat on the Senate Finance Committee, Abraham A. Ribicoff of Connecticut, said yesterday that President Carter's energy plan is "in shambles," and urged the President to withdraw it and come up with a new one.

Another generally loyal Democrat on the committee, Gaylord Nelson of Wisconsin, said he had been trying to find a reason to vote for the crude oil tax that is at the center of Carter's plan, but couldn't and called the tax "a bad idea whose time has not come."

And in still a third sign of the trouble the President's recommendations are in an oil-state Democrat was ready with a proposal for partial removal of federal price controls on oil, following the Senate's decision this week to phase out controls on natural gas.

One objective of the crude oil tax which is pending in the Finance Committee, is to discourage oil consumption by raising the price.

Sen. J. Bennett Johnston (D-La.) has drafted as a substitute a plan to raise the price directly by easing controls. The proceeds of the Carter tax plan would be rebated to the public, but the higher prices under the Johnston plan would go to oil producers. Johnston would take controls off newly discovered oil and give inflation increases to producers of the two categories of old oil. Most important, he would eliminate a "composite price" which Congress established two years ago.

This sets an average price which all domestic oil must not exceed. If the price of one category of oil goes up, the price of another must be pushed down.

If the composite price is eliminated, the price of one category could be allowed to rise without penalizing another.

Ribicoff and Nelson made their remarks to Assistant Treasury Secretary Laurence Woodworth as the Finance Committee tried again, and failed to come to some agreement on the crude oil tax, which when fully effective would raise about $14 billion a year. In an earlier session, it voted tentatively to strike the tax from the House-passed bill on which it is working.

Among other things, the committee is divided over what to do with the proceeds if it does impose the tax - whether to give the money back to the public to prevent loss of purchasing power, or give it to producers to encourage additional production.

Ribicoff told Woodworth:

Shouldn't the President admit his energy problem is in shambles? All the indications are it's just not going to fly. I think energy is the nation's No. 1 issue. Shouldn't the President and (Energy Secretary James R.) Schlesinger go back to the drawing board and come up with a new program?"

The crude oil tax, which the administration calls the center-piece of its conservation program, would tax the price of domestic crude oil up to world levels in three annual steps. The President hopes it would cut consumption by increasing the price of gasoline by about seven cents a gallon and produce similar price increases in other petroleum products.

Ten days ago the Finance Committee voted 11 to 7 not to consider the crude oil tax. Chairman Russell B. Long (D-La.) told members there would have to be an oil tax or there'd be no energy tax bill. He finally got them together again yesterday, after the Senate had shot down Carter's natural gas regulation plan, to try to agree on what the revenue would be used for if the tax were imposed. Long wants to use a good part of the $14 billion a year the tax would ultimately produce to encourage production of more energy - such as finding ways to extract oil from shale.

Sen. John C. Danforth (R-Mo.) said he wasn't interested in "having a program looking for a tax." Long replied that the committee had showed by its previous vote against the tax that "we can't have a tax looking for a program. What comes first, the hen or the egg? I learned long time ago that if you don't have either a hen or an egg you have to be the Almight to get either."

After 1 1/2 hours of squabbling, Long recessed the committee until today, saying it was obviously too far apart to agree on anything and that private talks were needed.

So far, the Senate Finance Committee has rejected Carter's tax on gas-guzzling cars, tentatively rejected the crude oil tax, and appears likely to reject or mutilate the proposed tax on industrial use of oil or natural gas which is the big oil saver in Carter's program. The only proposal approved by the Finance Committee is a tax credit to homeowners who insulate their homes or install solar heat.

The non-tax parts of Carter's program have also had hard going. The Senate was at work yesterday on a utility rate bill its Energy Committee gutted. It was to this that Johnston was contemplating adding his decontrol amendment.

The Senate approved another amendment by Gary Hart (D-Colo.) that would require utilities to make lower rates available to customers over 62 years of age. A final vote on the bill is expected to come today.

Bills were introduced in both House and Senate yesterday to prevent Carter from imposing import duties on foreign oil as Schlesinger has said he might if the crude oil tax is not approved.A possible $5-per-barrel tariff would greatly increase the price of oil in areas such as the Northeast which depend heavily on imported oil.