I think it would be overreach to say they intended to help Trump, but in defence of the idea, it is widely believed that Clinton was disliked by the FBI, and the decision to hit her over the emails just before the 2016 election was quite a popular one within the Bureau.
Frankly if this was the case, I don't blame them and I'd still support the action as I did then. That doesn't mean they were pro-Trump or intervened on Trump's behalf. As I said, the portrait painted of the bureau at the time between Comey's wind-sock behavior, McCabe's unaddressed criminal mismanagement, Strzok's and Page's nonsense, and the wholesale incompetence on display during that entire time period and the year that followed, was bare minimum one of bitter partisan division and unadulterated toxicity.
Between everything that happened at the time up to and including Slick Willie's wholly inappropriate meeting with Loretta Lynch and the highly suspect deletion of 33,000 emails from her server, the portrait painted of Hillary's email investigation is one that was concluded prematurely and without sufficient conclusion for political reasons. Comey himself stood in front of the entire country and admitted Clinton was guilty of what she was accused of doing, then announced he would recommend to not indict, even going so far as to cite the Espionage Act itself which specifically states negligence is not a legal defense.
Comey's a shit, but he was doing his job. When they found the emails on Weiner's laptop, he was obligated to re-open the investigation. Comey didn't leak the letter to the press -- and guess what, the story was going to break when the FBI petitioned the court for a search warrant anyway, given the high level of scrutiny on the Weiner investigation.
In terms of Trump, it is clear that the relationship between the intelligence services and Trump collapsed after his election win.
Please demonstrate there was one to begin with.