My sputtering '83 GSL
 

So I've rebuilt the carb, removed the rats nest and unclogged my catalytic converters. I've also replaced the spark plugs, wires and distributor cap.

My symptoms are as follows:

1. Low power
2. Sputters but runs much smoother with the choke pulled out. It accelerates a bit better with the choke pulled as well.

It had more power before I rebuilt the carb but I rebuilt it in order to replace the accelerator pump bc I thought it may have been what made it sputter.

I haven't had time to check the compression but I need an engine rebuild down the road anyway because of a dowel pin leak.

Any ideas would be much appreciated!

Still sounds like your carb isn't completely cleaned out or the fuel pressure is low. Check fuel
pressure (2.5-3 psi) and flow (about 1/2 gal per sec). If that checks out ok, then pull the carb
and reclean it. You have some small passages that aren't flowing at idle, pulling the choke riches
the mixture and is probably why it runs better.

Helps to use air pressure on the passages.

That's kind of what I figured. Is it possibly a bad fuel pump if my fuel pressure is low? I don't really know how to measure the fuel pressure but I can see fuel squirting out of the primaries while it runs.

Another way to judge fuel delivery is the float levels. Are they at the 1/2 mark in the windows?
Does it stay there when you give it gas? If so your fuel delivery is probably adequate at least
for getting idle working. I would bet the base plate of the carb has some of the minute passages
block that are key to the idle circuit.

You can try using SeaFoam in the gas or spraying the carb liberally with carb cleaner, you may
knock some crud loose and fix it.

My float levels are 1/2 way at idle. I'll see if they change any when I hit the throttle later this afternoon.

I'll also zap it with a bunch of carb cleaner.

My idle speed is really high (1800 rpm) but I haven't been able to find any vacuum leaks yet.

Well I got the idle speed back down to about 850 rpm by adjusting the idle speed screw.

I checked the flow rate from the fuel pump and it was putting out about 26 ml/sec. According the factory service manual it should be at about 18.3 ml/sec. I haven't had time to check the pressure yet but I borrowed a tool from my local Autozone so I'll check that asap.

An higher flow rate is not an issue that means you pump is pumping ;) the minimum is 18.3 ml/s or 1100ml/min (that is what the book says: Feeding capacity more then 1100ml/min)

The pressure must be between 2.6 en 3.3bar (I think) or between 0.26 and 0.33 kg/cm²

I borrowed a pressure gauge to test the pump but I couldn't get a reading. I may have to get a pro to measure it for me.