Car chokes when I accelerate on freeway

[Q451990owner]

I have changed the MAF sensor, replaced 3 bad injectors (1,2,8) replaced spark plugs, new fuel filter new fuel pump new gas tank , new air filter , cleaned throttle body.
The car will intermittently be missing on one cylinder, check engine turns on and it will go away after a minute and stop missing and check engine loght goes away.
On the freeway, if I kick down, it lowers a gear, and the RPM gets choked and it feels like the car wants to s*** down, when I let go the gas pedal the RPM returns normal and car is fine. What could it be,

[Q451990]

Maybe a bad fuel pump control module? It certainly sounds like a fuel issue - but if you just replaced the pump, maybe it's one of the higher pressure fuel pump modes that's not working... the controller runs the pump in one of three speeds depending on demand. You could use something like this with a longer hose and tape the gauge on to the windshield to get an idea of what's going on.

http://www.harborfreight.com/fuel-injec ... 92699.html

Heath

[OwnerCS]

I had a similar experience many years ago with a Cadillac. The muffler baffle had collapsed inside the muffler casing and would only allow a limited amount of exhaust to flow through system. I could drive it up to about 45 MPH or (equivalent RPM) then it would start stumbling and running poorly..

[Q451990owner]

Could it be the Bosch fuel pump? It all started when I changed it