I have an 86' h code firebird. it idles and revs fine in park but bogs down and dies when you get on the throttle driving it. Fuel pressure gauge says 6 psi which seems a little low, the right spec is 7.5-9 psi. I have a clear in-line fuel filter which you can see isn't full, so I know there's a fuel delivery problem. I sprayed a lot of carb cleaner in the carb and changed both filters with no diffeence. I pulled the old pump off (mech on block), and it only had an inlet and outlet, the pump I got from napa (carter m6626) has a third fitting. As best as I can tell, the pump I took off is a carter 6900, which is definitely not right


My question is, on the good pump is the third fitting for a return line from the carb (which I don't have) and if I just cap it off on the pump will that create a problem/leak?

 

Ran into an even bigger problem today. Capped the pump off and went to put it in and see what happened, but it wasn't even close to fitting. Comparing the arms on each they're pretty much completely different. Anyone ever seen something like this before?