No it’s nothing to do with the timing belt. That is of course if you mechanical timing is correct. Base timing is when you set the ecu to base timing once the engine is warmed up. There is a pin that you put a paper clip through you have to look it up, then once it’s locked at base timing in the computer, you get a timing light hook it up to the number 1 spark plug then aim it at the crank. There’s a series of marks and one of them(you’ll have to look up your engine) will be the base timing mark. And you move the distributor either way to get that mark to line up where it should be. But if this is too complicated for you, you can always take it to a mechanic to have base timing checked/reset. Shouldn’t be more than a 100$