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Car occasionally won't start and loses power and dies

My car sometimes starts and runs. Every other time I have to give it gas to get it to stay on. What could this be? It will die if I take my foot off the gas too quickly or halt too hard. Is it my fuel pump or maybe my idle air control valve? I checked the sensor for the IACV but it didn’t help any.

Year, make, model, miles?

Presuming this is a modern electronic fuel injected vehicle, idle air control valve, throttle position sensor, or maf/map sensor are what I’d be looking at first w/that symptom.

The IAC valve is not a sensor. It is what the name implies… a valve that opens and closes as directed by the computer. Your problems could be several different things. Removing the valve and cleaning it is typically not a big deal. I would give that a try. But more info is needed as others have pointed out.

1995 mazda 929 71k miles

Start w/the idle air control valve for a 1995. It may be necessary to clean the throttle body too, if the throttle valve is sticking.

My first reaction would be iacv also, but could be a vacuum leak which is easier to check. Also would like to check fuel pressure if no vacuum leaks and turns out that iac is good. But that takes an inline pressure gage which is a little more involved than normal.

Alright thank y’all for your help I will check these out and what I can’t I’ll get done at the shop.

So I checked the IACV and the throttle body. I haven’t checked fuel pressure as I am not sure how to go about using an inline pressure gauge. Maybe I need to change my fuel filter then check that out?