Car running like garbage, frustrated
 

Hey everyone,
On my 1986, I recently replaced my fuel pressure regulator to try and fix an issue with a slightly shaky idle, as well as hesitation from a stop. Well, while I had the plenum off, I fixed a broken vacuum line that (I think) connected to the EGR valve. I noticed a fair amount of carbon in the plenum so I went ahead and cleaned it out with some carb cleaner, and put everything back together. When I went and drove around, the car drove even WORSE than before. The hesitation is horrendous, and is borderline undriveable until it is warmed up (175-180°F) the hesitation is more like a surge, as it will ramp up and down a bunch, and even backfire a bit. From my knowledge of dirt bikes it feels like a lean condition, but I am unsure.

As far as I know, the car is stock, which is why I used a stock replacement FPR bladder, but who knows, maybe the previous owner set it up for oversized injectors, and it is just not getting enough pressure from the stock regulator, but I also am unsure of how to check what type of injector is used. I currently don't have access to a fuel pressure gauge, or else I would definitely be checking that. I also do not think that it is a fuel pump issue, because about 2,000 miles ago it was replaced along with the fuel sender unit. I also have ensured that all of my plug wires are connected.

I have spent a long while looking at other issues that people have

Any help is welcome, thanks.

(also please do not criticize me too bad LOL, I'm only 18 and trying to find my way around a nearly 40 year old car, so have some grace for me)

Try removing the vacuum line from the egr valve and see if it runs better, Egr valve should be closed at idle.

Without a fuel pressure gauge you're kinda shooting in the dark troubleshooting fuel issues. They're fairly inexpensive at harbor freight. Go get one and set the fuel pressure properly. Then if that doesn't solve the issue move on.