Ok, I have a 96 Ram 1500 4x4 with a 5.2l, 110K miles. Recently I have notice some loss of power and fuel mileage. I have been planning on doing a tune up but have not had the time. Yesterday I was going to work, the truck was running like it has been until got to temperature then started to vibrate a little. Around 40-45 mph while giving it gas. If I let off the gas, shaking stopped. By the time I got to work, the CHECK ENGINE light was on. I did the key dance and got 43. Looked that up and came up with a plan. So, when I left work same thing with the truck on the way home but the shaking was worse. I replaced the plugs, wires, rotor, cap, PCV and air filter. (all of these were due anyway). The plugs had some signed of maybe it was running hot at one time. And that makes sense because I had a bad thermostat about a year ago and the truck was running hot. #8 had some electrode degradation. Started it up and it sounded much better. I took it down the road and it was running great…..until it warmed up. Then it started to shake again around 50 mph. Let off the gas and it stops. If I make it down shift, it stops. If I take off OD, it stops. I checked the CAT, it does not rattle when I bang on it With engine a normal temp the temp of the in and outlet of the cap are the same so I don’t think it is clogged. I am thinking O2 sensor next because I don’t think I have ever changed it, but wouldn’t that cause the performance to be bad all the time, not just as I described? I don’t have and loss of oil or water so I don’t think it is a problem with the head gasket. I have seen some post similar problems with an answer of fixing the routing of the plug wires but the truck is damn near 20 years old and 110k and this has never been a problem before so I don’t know it I buy that. Any ideas were I should move to next. Coil, Fuel pump, TPS, O2 Sensor, Injectors. Thanks. Donnie

 

Move this thread to the correct forum.

You have a blown plenum, probably a failing pre-cat O2 sensor, and a cat that is working on clogging. Standard fare for the 2nd gen Rams. Check out the Plenum thread stickied at the top of this forum. That will tell you have to verify the problem, and what needs to happen to fix it.

I am about 98% sure this is indeed your problem.