Chrysler Repair: 99 Town&Co. Oil Light is staying on with noisy engine., tappet noise, haynes manual

Question
Hi Roland, thanks for the infromation yesterday. I have the 3.6 V6 engine in the '99 chysler T&C. The engine did start this afternoon. Oil light was out for about 10 sec. then came back on. I was able to change the oil (black as coal) and the filter after adding some engine cleaner. Started the engine back up and it seemed a little better noise wise but the oil light did flicker then come back on. I decided to do one more cleaning and oil change. Since the engine is still able to run, I figure this is a good thing. I will need to check out the oil pump as you stated yesterday. I am able to do just about all my own work, I am not sure on this since I have read I would need to have an engine hoist. What can you tell me about this changing the oil pump? Is this the only thing that could be wrong? If I need to bring the car to the shop, should I let them figure out the problem or let them know what I think is wrong? Thanks again for your very quick response and help.  Hope to hear from you soon,  Chris.

Answer
Hi Chris,
I am not clear about the rpm at which you are getting the warning light. If at idle, it may be that the pressure switch is closing at too high a pressure (giving a false low reading) but the fact that you heard tappet noise is reason to believe that the pressure was too low. The manual points out by the way that if you have the crankcase too full that you can cause foaming of oil in the pan which then cause the pressure in the output from the oil pump to be lower than it should be due to the intrapped air. So was your crankcase too full when this problem started?
Getting a calibrated pressure reading would be useful, plugging the gauge in at the pressure switch tap. The other corrective possibility is to increase the weight of the oil one or two steps which will raise the pressure.
To assess the pump and the input pickup you do have to remove the pan. My copy of the Haynes manual does compare favorable to the official Chrysler shop manual as far at the sections related to the oil pump/pan removal and assessment. So I think with a Haynes manual you should do fine. I hope you can get around doing that task, which will require that you jack up the van on both sides and support it on jack stands. By the way, the manual shows a 3.3 or 3.8L not a 3.6L so I assume that was a typo in your response. The 3.3 and 3.8 are mechanically identical.
Roland