The way it was explained to me is all semiconductor devices would be destroyed, your alternator, fuel injection computers all GONE! The entire power system, transformers, sub stations and all switching systems would be toast. The only fuel motors that would run are point ignition with carborators and mechanical injection diesels. Not to mention where are you going to get gas? No gas stations I have ever seen have connections for generators? I have seen gravity fuel tank set-ups for city and school bus fuel terminals. Of course there are different levels of exposure, distances and things like that to consider.
1) There is no EMP device/nuclear weapon large enough to blanket the country with this type of effect. And if enough nukes went off to do that, you would already be so inundated with radiation it wouldn't matter.
2) Not all electronics would be toast. The EMP is picked up by the conductors (antennas) that cause voltage spikes that ruin sensitive electronics like FET's ~ in the process usually turning on these devices (if not destroying them) all at the same time (=magic smoke). Many bipolar transistors and diodes (alternators and generators) would be fine. They tested this in Hawaii and only a few microwave RF links went down.
3) It's not hard to walk over to the filling location at the gas station, take the cap off, and put a hose/manual pump down the hole. You can even use the bean can on a rope you are using on your deep well for this.
4) Transformers might get damaged, but most of them are oil filled so I doubt if a temporary flash over between the windings would take them out completely. If they were powered at the time, sure. But we would see a solar flare coming, and if it were a threat, we would shut the grid down so the flash over's don't burn everything up. I hope.
5) A huge solar flare might do it, but most of our serious infrastructure is hardened for this. Even google and microsoft keep their servers at the bottom of the ocean for the benefit of temperature stability, security and RFI mitigation. Swap out a few fiber optic controllers and you are back in business (at least to a point we are not crippled completely). With the main part of the internet running on plastic fiber and their controllers double-shielded, the satellite links between these systems would be the only problem, but if the satellites in space survived, this would be a short-lived issue. We will know if a solar flare is coming, we have plenty advanced warning for it, so you will definitely have time to unplug your routers and keurigs