Hi since a bought my car (used) noticed that sometimes when starting the engine it spikes the rpm to much. Is not big deal I know but I'm not sure if is normal because it doesn't always do this, almost always but not always and because it doesn't feel "natural" at all, is like it revs on propose after starting. It starts, revs up to like 1500(normal) keeps it for half a second but then when you would expect the rpm to drop it jumps again to 2k 3k and the it drops to idle.
Only does this when the engine is started already warm, cold starts are fine.
Is a vw mk4 1.6 NA, throttle body is driven by wire