Hello i just bought this dodge truck its a 1994 dodge ram 1500 2x4 5.2L 318 motor in the morning when the motor is 100% cold, when it is started it runs real rough back fires, splutters, shudders, shakes and when you go to put it in gear or in reverse, the motor will stall out, sometimes it will even stall if you let it just sit and idle rough. now the weird thing if you let the engine sit and warm up to about 210-230 degrees the motor will smooth out perfectly and run strong. i have replaced the spark plugs, spark plug wires,Idle air controll valve, coolant temp. sensor, i have rented the fuel pressure guage and when i hooked it to the schrader valve and turned the truck on the pressure was around 48-49.5 lbs of pressure i dont know if that is to high or what. someone also told me it is possible to be a fuel pressure regulator, iv looked all over the fuel rail for this thing and can not find it anywhere is it located on the pump in the gask tank? someone else told me vacuum leak i sprayed carb cleaner around and it never reved up or choked, so im at a loss iv spent alot to try fix this thing i hope someone here knows how to fix it or has herd of this i am new to this forum i just made it to get help please email me at xxking9@yahoo.com or call me at 804 972 0021 thanks alot
mat

 

sounds like your cat is clogged.

 

Could be clogged fuel injectors. My 92 had a fully clogged injector and half clogged one. The plugs from those 2 cylinders always fouled with excess oil( thought it was bad valves). It would backfire up into the air cleaner and was very hard to start. A friend of mine has a car and he didn't have power going up hills and his cat was clogged but he didn't have any other symptoms like you have. Don't know what your plugs looked like when you replaced them.

 

Fouled injectors are so common that I hestitate to say that I don't think that is your problem, but if your motor is running perfect once it warms I doubt it will be the injectors. Plugged injectors stay plugged all of the time. It could be the manifold temperature sensor. My Ram would buck and jerk when it was cold. Replacing the manifold temp. sensor did the trick. Then I cleaned the injectors and it stopped skipping and backfiring (which it was doing all of the time, cold or warm).