Hello i recentley bought a 99 jeep cherokee sport with 208k miles on it.The jeep ran great for a week then i took it to work and when i came back to go home the car did not want to start it would crank but no start. I dropped the tank and put a new pump in it and then tries it and still no start. I finally put a new distributor cap and rotor and now the car starts and idals.But now when it idals it slowley starts to loose fuel pressure and dies.I drive it for half a block and starts to slow;y die idk what to do anymore. Help!!

**UPDATE**
I picked up my car from my friends house i left it there over night since i didn't want to drive it back with all the stalling. I trn the car on and fired right up and the car drove all the way home without stalling or dieing. I did notice that it would run if i kept it below 2k rpms and if i gave it gas above that it would start stalling.Now my question is could it be a sensor thats going bad that makes me loose pressure and kill my car???? what could it be??

 

Did you confirm the fuel pressure is dropping with a gauge? If so I wanna say clogged fuel filter.

 

1. Check Engine Light on (if yes, what are the codes)?
2. What does the fuel pressure start at, and what does it drop to?
3. What brand of fuel pump did you use?

 

yes i confirmed with a gauge idols at 45 then drops to 0


1. no lights are on just the air bag light
2.pressure starts at 45 and drops to 0
3.i am using a denso fuel pump that i had in my garage that was working fine in my other car.

 

Then yeah I would have to say the filter is clogged, or the pump's wiring has an issue. Got a voltage meter?

 

If power to the pump remains solid, there's a good ground and there aren't any leaks, the Pump or the pressure regulator might be bad. Problem is they're both back in the tank.
Since this problem started after you changed the pump, that'd be my first suspect.

 

Yeah i can get a volt meter and check what should the reading say.

Yeah i might have to drop the tank again and check . its crazy it was fine and out of the blue it just started to have these issues.

 

14 volts with the engine running, with the engine off it should read the same as the battery itself (Which when fully charged should be a little above 12 volts)

 

Does any one have any more advice on what it could be.

 

**UPDATE on page 1

 

Still a bad fuel pump. There is no sensor that controls fuel pressure, that's done by the pump (generates the pressure) and the regulator (limits the pressure to spec), both back in the tank.

 

next time, try removing fuel cap as it may be creating a vacuum.

also, could be catalytic converter.

lastly, maybe the asd relay...??

 

UPDATE: car has been siting like a week i came out and drove it around the block same thing will run under 2k but anything over it will bog and die. Could it maybe be the fuel pump i don't want to buy one and find out its not since there like 200.

 

Check the voltage to the fuel pump at the pump connector, preferably while the fuel pressure drops.
Check the ground connection to the fuel pump.
Change your fuel filter.
Still have the same problem? It's either the pump or the pressure regulator. There isn't much else that can cause fuel pressure to drop.

 

Sounds good i will try all this test and hopefully find the problem.