95 F150 with 5.0 and 5speed... wont stay running at stops and chugs/jerks during acceleration. I replaced the fuel filter to no avail. The fuel pump seems to change pitch (the whining sound gets a bit higher) when I switch to the front tank.

If I floor it, it is fine. I'm a bit confused as to what it could be. The check engine light comes on sometimes, but then goes back out.

HELP!

Thanks

 

IAC Idle air control or maybe a vacuum hose came off or a vacuum leak.

 

You may also want to check out your EGR valve it is on your intake. I had the same problem.