Ok, this is the poster who prior asked how to replace their inlet coolant pipe. Tell us all the stuff you removed to do this job, then we’d be better able to venture a guess. If you were messing with the valve covers, double check that all the parts of the pcv system have been reinstalled correctly. Incorrectly configured pcv systems can create huge vacuum leaks, and cause this sort of symptom. When I diddled with that pipe (as part of replacing the water pump) on my Corolla I didn’t need to remove the valve covers, just loosen them. I did need to remove hoses connected to the throttle body, such as the canister purge hose. And I had to remove the electrical connectors at the distributor. OP’s problem doesn’t sound like an electrical problem though. Good idea to do the basic battery/charging system test even so.
I experienced one little engine performance glitch now that I think about it. In order to lift the valve cover enough to remove the timing covers I had to remove the spark plug cables from the plugs. I just left the cables in the holes, but forgot to push them back onto the plugs upon reassembly… So double check the cables are properly connected to the spark plugs.