p1179 was the vac line on my FPR. Check the plug on the top of the fuel pump housing and under the drivers side rear wheel well. Looks for burnt black areas. Mine would do that due to a burnt harness.

 

next time its not starting. try to take off the gas cap, then start the engine. may be a clogged fuel fill vent hose. neither excess pressure or low pressure are good. I bought my disco in pretty bad shape. new fluids, filters, plugs, wires, wax job, fuel treatment, cleaned throttle body and oil separator ($200 later). Its running better than most of my friends new and expensive American trucks....... you don't have to be a mechanic to keep these trucks happy. all you need is basic tools, and a understanding wife. These trucks are a passion.