Unfortunately, I have a problem with my 2.0 DOHC Sierra And it’s more and more often that I have to pull it off when I’m driving and the car sounds like it’s only running on 3 pots. That with som short jerkler is so at about 1500U/min to 2000U/min. Then it’s going to go again and then it’s going to go on normal. In the upper speed range there’s nothing more to remember about nem jerking or anything like that. Unfortunately, can’t ever imagine what this should be like if it’s on the open air filter? Couldn’t be more than spark plugs, ignition distributors, gasoline feed or control part to me. But if that’s how it gets “s worse” from time to time. Then I don’t have any other question about how to change the DOHC’s spark plugs? There’s a trick or I have to break my fingers as close as it is. Would it be nice if one of you has no idea.