Mmmm, I Don't Know.

It is difficult to comment on that. Not that it couldn't have happened but there are some issues:

The Iranian navy intercepted a US submarine in the Strait of Hormuz and forced it to surface and change its course, Rear Admiral Shahram Irani told reporters on Thursday. However, the US has denied the claim. According to Irani, the nuclear-powered USS Florida was approaching the strait in complete silence when it was detected by an Iranian Fateh-class diesel-electric submarine. The Iranian vessel “forced this American submarine to come to the surface and cross the Strait of Hormuz on the surface of the water,” Irani said, according to Iran’s ISNA news agency. Irani added that the US submarine attempted to enter Iranian waters, but changed its course following a warning from the Fateh. The admiral called on the US to explain why the Florida attempted to violate Iran’s borders, and declared that American vessels “must observe all international rules from now on.” The US denies that the encounter ever took place. “A US submarine has not transited the Strait of Hormuz today or recently," the commander of the US Fifth Fleet, Timothy Hawkins, told Reuters. “The claim represents more Iranian disinformation that does not contribute to regional maritime security and stability,” Hawkins added.

And here is the issue, which is confusing. USS Florida is an Ohio-class former Strategic Missile Submarine (SSBN, aka Boomer) which has been converted to SSGN, meaning that this old lady carries now 154 TLAMs and is specifically designed for primarily land-attacks with conventional means (Tomahawks also can carry a nuclear warhead). TLAM's range in its most popular version--Block III/ IV--is around 1,600 kilometers, so you can easily draw the circle from say Bushehr Nuclear Plant (a possible target for attack) and you will see yourself that to attack it, the same goes for Tehran, it is enough for modern SSGN to be merely in the Gulf of Oman (and Arabian Sea) never entering dangerous Persian Gulf through an extremely narrow Strait of Hormuz. Why would one do that? I know, I know--PR and all that, but ASW has its own logic. 

Moreover, no matter how good Iranians are, but I doubt that sonar and sensor suite on their single Fateh-class sub measures up to updated Ohio-class SSGNs which still remain one of the most silent in the world. This is not to say that they cannot be detected, they certainly could be and have been... by Soviet and Russian SSNs. But something tells me that even if the contact and even ping between Fateh and USS Florida has happened it didn't happen anywhere near Persian Gulf, plus... and here it comes--Iranian Navy has three Russia-built Kilo (pr. 877) SSKs and those for decades had a title of "black holes" in the sea due to their extremely low acoustic signature. And yes, those guys, have been involved in hide-and-seek with US Navy's Los-Angeles and Virginia classes everywhere around Russian littorals. So, could it be that Iranians confabulate? Absolutely! But could it be, considering a steady loss of competence in the US across the board, that someone wanted USS Florida in the Persian Gulf for PR purposes? Absolutely! So, don't torture me with the questions--I don't know. Otherwise I will get engaged and write massive posts on Operational Sweeps, Detection Probability Densities and other "lovely" ASW thingies with a lot of math... fade in the dark with evil laughter...

;)))