I have a 99 D that I have owned for the past year. I've already fixed a few things on it over the past year (rad., water pump, new hoses). I have come across a few problems this month that I would like to fix becuase I love this car and want it running right. First is the heater not blowing cold. I searched and saw that most say to flush the heater. If anyone has any ohter advice that would be great. My other problem is an oil pressure guage malfunction. The guage drops to 0 and the check engine guages light comes on any time I use the brake or go through a fast corner. The engine never sputters and doensn't seem to be bothered, but the constant dinging is annoying. I have no idea what is causing this. My final problem is my right tail light. when my headlgihts are on the light comes on but it doesn't get brighter for my brake light. Is this just a bulb or a loose wire or switch. Sorry for the long post but I would like to get these problems fixed. Thanks for any help.

 

Just a bulb for the brake light. There are 2 filaments in our brake lights. I would say take a look at this link for the oil pressure. it may be the pump and/or sludge buildup in the pan. https://dodgeforum.com/m_706903/tm.htm

 

IK:
Your first priority should be the oil issue. Make sure the oil level is full as what you describe can be caused by a low level that sloshes to one side and uncovers the oil pick up onhard turns. If the level is ok, I would replace the sending unit for the guage as they are inexpensive and thus easily ruled out. The 98-99 D's with their 5.2/5.9 motors are known to have such issues in later years sometimes especially if not maintained with proper oil/filter changes.

As you might already know, there is a plenum gasket on the bottom of the factory 5.2/5.9 intake that often fails allowing oil to be drawn into the engine and burned. If you are experiencing frequent low oil levels and/or pinging under acceleration, this may be the case. To get an idea, take a flashlight, remove the air hat from the intake and look down inside. If you see oil/wetness it is a good bet your gasket has gone south.

Re the heater issue: you say that your heater wil not blow cold air? Are you trying to say thatyou can not turn it off, or that your A/C is no working?

These couple of posts should help you get started.

Good Luck. Don

 

thanksfor the advice. I'll look into the oil situation this weekend and give an update.

My bad on the heater not blowing cold aprt. I meant the heater is not blowing hot.

 

When you changed all of your hoses, did you change the thermostat? Because, if you did, and you put a cooler running thermostat (180 degree) it will not blow nearly as hot aswhen you had thestock temp thermostat. I know this because I intensionaly changed my thermostat to the 180 degree to help my 5.9 run cooler. I live in south Louisiana and my engine would run really hot in the summer during stop and go traffic. It helped the engine run cooler in the summer, but, it also ran cooler this winter. Which means my heater doesn't blow as hot as I'd like, but, I'll take that instead of over heating in te summer.