The work and pensions committee has launched an inquiry into contingent charging on defined benefit transfers.
MPs are asking if there is any evidence of unintended harm caused by contingent charging when it is used for these transactions.
The committee had already called on the Financial Conduct Authority (FCA) to ban contingent charging in its report into the British Steel Pension Scheme published last February, saying it considered the practice to be "a key driver of poor advice".
The committee stated it had received "worrying evidence" about the financial advice given to members of the British Steel Pension Scheme after they were given the option to transfer their pensions into defined contribution schemes.
But the regulator decided against it in October despite finding widespread problems in the suitability of pension transfers.
The regulator stated contingent charging was a "complex area" and poor advice on DB transfers had a number of causes.
Its analysis had shown contingent charging was not the main driver of poor outcomes for customers but because of the significance of this issue to "all stakeholders" it confirmed it would carry out further analysis and consider action if appropriate.
Frank Field, the committee's chairman, said the latest inquiry was designed to provide the regulator with further evidence of such consumer harm.
He said: "The FCA has confirmed to me that it shares many of the committee’s concerns about the scourge of contingent charging.
"But to tackle this, and to protect consumers from the vultures circling around their pension pots, it needs more proof of what is really happening to people.
"It has explained to me the complexities of contingent charging, and how it needs to carefully consider its possible interventions so as not to cause unintended harm, particularly to vulnerable customers.
"The FCA has said it would welcome the committee’s help to find out more, and we’ll be happy to do everything we can to make sure we get the right safeguards in place."
The committee said it wanted to hear from anyone who has been affected by this issue and from others who have views on banning contingent charging.
In particular, it has asked the following questions:
-Does contingent charging increase the likelihood of unsuitable advice?
-What would be the impact of a ban on contingent charging on consumers and firms and how could any negative effects be minimised?
-Are there any alternative solutions that would remove conflicts of interest but avoid any possible negative impacts of an outright ban on contingent charging?
Paul Stocks, financial services director at Dobson and Hodge, said he felt contingent charging was being made a scapegoat for bad advice.
He said: "Whilst contingent charing creates a conflict of interest, this is one of many clients can face – firms therefore have to manage such conflicts of interest and it is, of course, a regulatory requirement to do so.