Rough running

[94century]

I have a 94 Century with the 3.1, and I am having a problem with how it is running. It cut off on me on the way home one day and it would start back but I had to pump the throttle to keep it going. After about one hour of doing that it would not start at all. So I just let it sit at the house for a couple weeks, and then tried to start it. It will start with starting fluid, and it would idle after a minute or two of fighting to stay running. when it was idling if I eased on and off the throttle it stayed running, but give it a quick blip and i would have to fight it again. It is like the fuel is not keeping up with the throttle, also it sometimes backfires when i blip the throttleJust replaced fuel filter(it was full of dirt) and fuel pump cycles on and off. If I hold the throttle down will starting I can smell gas. I took out the Idle Air Control Vavle and cleaned it , but to little effect. What now? TPS, Camshaft sensor, IAC, Mass Airflow, What?

[GTP Dad]

Check the fuel pressure regulator to make sure the pump is maintaining the proper fuel pressure. I would believe that your problem is a bad fuel pump. If there is no fuel pressure that is a sure sign. You can also replace the fuel pump relay with another one to see if maybe that is the cause. A lot cheaper than a fuel pump.

[94century]

Ok, I replaced the Idle Air control valve and it did run better. Now, when I ease the throttle it revs up fine, but if I push real fast it bogs down. When the rpms are low and I push down it wants to cut off, but I would guess @ 2,000 rpm it wil rev up, but sound and run horrible as it revs up. I drove it up the road and if its flat ground it will get up to 60 mph. If it has to pull the slightest hill at any speed, it will want to bog down. Could that be TPS, A timing problem, EGR,

[GTP Dad]

The egr could cause the problem. You can remove it and clean the passages. and then replace it. They do block up occassionally. I would look at the TPS. It may not be sending the correct signal to the computer. They do go bad and poor throttle response is usually a good clue to something going wrong.

[94century]

check tps, voltage output ok, will try egr. Also I took off the ignition coils and tested them, tested ok, but now the car backfires through the intake big time

[GTP Dad]

You may have the wires on incorrectly that would make it backfire through the intake.

[94century]

Yep you were right its the fuel pump. It is putting out a whole 6 PSI. Thanks for the help