89 sentra surges

Trying to find out what’s wrong with my 89 Sentra 4 spd. Over the last 3-4 months when it’s first started it runs a little rough and has a rich smell to it. When put into gear especially at low speeds it starts to surge like its running out of gas. Even when warm - at any speed, when you very slightly decrease acceleration it surges. But when you just accelerate it stops. And when coming to a stop it stalls but will start right up again. Any ideas? My normal car is a Chevelle so I don’t know much about these foreign cars.

You might check for a leaking fuel pressure regulator. http://www.rockauto.com/catalog/moreinfo.php?pk=940201&cc=1212758

If the fuel pressure regulator diaphram has a leak unmetered fuel enters the engine causing the engine to run rich. The leaking regulator also doesn’t allow the proper fuel pressure to reach the injectors which causes the engine run rough or stall.

Locate the fuel pressure regulator on the fuel rail. Start the engine and let it idle for a minute. Shut the engine off and remove the vacuum hose from the regulator. If gas leaks out of this connection replace the fuel pressure regulator.