1994 Mustang GT bogging down/Fuel pump Problems??
 

My 1994 manual GT was having idling problems so I cleaned the IAC which seems to have solved that problem. But after driving about 15 miles, the check engine light came on and the car started to falter... i.e. it was popping or jumping as if it was about to cut off - as if it was out of gas. I had about less than a 1/4 of a tank so I visited a gas station and (after cutting it off) I filled it up and it seemed to run fine for about 15 minutes before the same thing started happening again. It starts up perfectly fine and I think I can hear the pump kick in. I mashed down on it and it just wasn't getting all the way up in the RPMs. And the car would barely make it up a hill!!! AFter making it back home, I let it sit over night and it seems fine, but I haven't drove it.

To note, I also recently had to change the gas tank because it had a mini hole into it.

I don't think the IAC has anything to do with it but could I be wrong. Could it be the fuel pump telling me it's going bad? I always thought that a fuel pump gave without warning! What about the fuel filter or water in the gas? But I didn't think it would clear up overnight and then happen again.... Please provide suggestions. Thanks!!!!

It could easily be the fuel pump but you'll have to find somebody (local mechanic) that has a fuel pressure gauge to be sure. It can also be water in the fuel, and heck you never know even the filter. I'd probably start by having the pressure checked, it only takes a second to do.

Just for the heck go out and just make sure your MAF meter didn't get disconnected by mistake. I once had a very similar experience. Of course I was over 100 miles from home when my car started to buck and feel very low on power. After a few miles it cleared up but then started again a little while later. When I arrived at the next rest stop I opened my hood only to find that the MAF was disconnected. The plug was just barely on there which is why it would come and go.

I had the same problem in my '88. When it was cold I wouldn't have a problem but after a few minutes there was no power and it would start popping and backfiring. I swapped out the fuel pump for a 255lph and it ran awesome after that.