Stall on start up

[grizzlyxjim]

So I have my 99 mounty with the v6 drove up to the gas station today and went back out tried to start it to leave it started idled for a second and died, did it a second time and I really had to crank it for it to start, drove home and idled it for a good 15 minutes to see if it was gonna die again and it didn't (its automatic too) I had the intake manifold replaced just a couple months ago, doesn't feel like a vacuum leak. New cap and rotor a year ago, hoping it isn't the beginning of the fuel pump dying. It bothers me when things like that happen to my vehicle. A lot of people might write it off as a fluke but I can't let stuff like that go haha. It does need a new oil pressure sending unit, when it's cold it won't read, the typical thing, but it's been warmer and that isn't a problem the two wouldn't be related I don't think. (thinking outloud) So anything I've missed? Any thoughts or suggestions? Will probably check for vacuum leaks but I'll be mad if the intake manifold blew, I paid 300$ 2 or 3 months ago for it to be replaced.

 

[1998Exp]

No Check Engine Light, I presume, or you'd let us know about it. Nevertheless, it probably makes sense to scan for pending codes.
In addition to the possibility of a bad fuel pump, you may have a bad (or badly connected, which is more likely) ECT - coolant temp sensor.
And, incidentally, your 99 Mounty uses distributorless ignition, so there is neither cap nor rotor. If someone charged you for replacing those, ask for your money back.
Good luck.

 

[grizzlyxjim]

My bad on that, the receipt was in the glove box from a previous owner, its plugs and wires not cap n rotor I'm used to working on older vehicles this is actually the newest one I have ever owned. So I just came in from hooking up my elm327 Bluetooth code reader and it was giving no errors, you are correct no check engine light. The vacuum psi was a little high I read it is supposed to be between 20 and 25 and it is coming in at 26.4 so it's got a leak somewhere maybe. I think it is the IAC, it looks like a cheap aftermarket one, I inspected all the hoses, I will have to get some brake cleaner and give it a spray test. It has 162k on it Been reading the fuel pump starts to get weak around 150k so I am going to start saving up for that repair.

 

[koda2000]

If you had a vacuum leak your vacuum would be lower, not higher. I'm guessing it's your fuel pump, but I'd also check your crank position sender and it's connection.

 

[grizzlyxjim]

Makes sense. I wonder why it was reading high when the intake manifold went bad and went back to a normal range when it was replaced