AggieIROC13

Howdy, I bought a 1990 Camaro Iroc-Z on Monday this week, I have not had any problems up until now, and it scares me. When I am idling, most the time the engine sounds like it is having trouble breathing, as in it has high rpms followed by low rpms like it is having trouble breathing. Initially (and possibly still) I thought that there was a vacuum leak but I was unable to find one (I could use some help finding where I should look). I also thought that the fuel filter might be clogged, however earlier today it had no problems what so ever. Also, It wont accelerate well at all, in fact it wont get above 80 mph and I went 100 earlier in the day, what could be the problem? Could it be a vacuum leak or a fuel filter problem? Or is there another problem that I should look into. Also, would it be easy to replace the fuel filter? I can't find it and I would need a step by step on how to change it. Thanks

AggieIROC13

So I am pretty sure The problem is the fuel injectors, does anybody know how much it costs to get them replaced?