Hi, this is my first post. I own an 87 gxl. It idles high around 1100rpm-1500rpm. When I first start her, she raises to 750rpm and tries and succeeds to die and stall unless I hold it to 1500 for a couple of seconds. Then she smooths out at 1100. She also bounces and pulsates, but being that its stock ports, I'm pretty sure that's not right haha. I've tried adjusting the bac valve, throttle screw, and the tps stopper. Just makes everything worse. I sprayed a whole can of carb cleaner and no vacuum hose holes that I'm aware of? Please help!!

 

Typically, start and die issues are caused by a significant vacuum leak. In addition to the vacuum lines and hoses, vacuum leaks can happen at the injectors and the LIM and UIM gaskets. Vacuum leaks aren't very glamorous and can be a pain to find and fix, but this may be your problem.