El-Erian, who has $2 trillion in assets under management, said that the reason for the Fed drawing down its $85 billion-per-month bond-buying program would be crucial.
"Now the key issue is to ask why would it be postponed, and there's two possibilities," he said. "It's postponed because the data is weak, and that's not good news. Or it's postponed because they're less worried about the costs and risks of prolonged reliance on unconventional policies.
(Read more: Top 4 stocks to weather a market pull-back)
"So, if it's pushed back for the second reason, the markets would like it. If it's pushed back for the first reason, the market would like it a lot less."
El-Erian said that the factors that would bolster the second reason for Fed tapering – "escape velocity" – were not occurring fast enough, "and that's a real prob for the market."
"We haven't had to reconcile that because profit growth has been so strong and because companies have had cash to give back to investors, but remember the disconnects," he said. "We've have a disconnect between the macro and profitability. We've have a disconnect between profitability and corporate investment. And we've had a disconnect between GDP and employment. So, at some stage we've got to reconcile these disconnects, and the longer they persist, the greater the risk to the markets."
— By CNBC's Bruno J. Navarro. Follow him on Twitter
— CNBC's Katie Young contributed research to this report. Follow her on Twitter:
Trader disclosure: On Aug. 13, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Josh Brown is long VGX; Stephen Weiss is short AAMRQ; Stephen Weiss is long M; Stephen Weiss is short JCP; Stephanie Link is long AAPL; Stephanie Link is long JPM; Stephanie Link is long WFC; Stephanie Link is long CSCO; Stephanie Link is long FB; Stephanie Link is long EBAY; Stephanie Link is long YUM; Michael Murphy is long BAC; Michael Murphy is long C; Michael Murphy is long MSFT; Michael Murphy is long LEN; Michael Murphy is long TOL; Michael Harris is short CME Gold futures ; Michael Harris is short CME 10-Year Treasury Futures.