With a missing float, your fuel gauge will read "full". GM has always used a different style gauge than everyone else. As the float drops, the sending unit electrically pulls the gauge needle down. Most likely the new float got hung up on a baffle in the tank. You can verify that by unplugging the sending unit wire. The gauge should go to "full" again.
For the oil pressure problem, start by removing the sending unit to install a mechanical pressure gauge so you can see what the actual pressure is. If it really is too high, suspect blockage in the pressure relief valve in the oil pump. That commonly results in exploding the oil filter.
When the Engine Computer detects a problem, it sets a diagnostic fault code and turns the Check Engine light on to tell you. Chrysler makes reading those codes yourself real easy. It's almost as easy on your car but you have to find the diagnostic connector under the steering column. Use a paper clip or piece of wire to connect terminals "A" and "B" together. Those will be the only two terminals right next to each other in one corner of the plug. Turn on the ignition switch and watch the codes flash out with the Check Engine light. Count the flashes for the first digit, there will be a short pause, then count the flashes for the second digit. After a longer pause additional codes will flash the same way if there are any.
Tuesday, January 14th, 2014 AT 9:51 PM