Buick/Olds: 1996 Buick Park Avenue loss of oil pressure, buick park avenue, pressure sprayer

Question
My 1996 Buick Park Avenue  with a 3.8 motor has lost oil pressure.  It has synthetic oil in it and has been changed regularly as per manufacturer's recommendations.  We've changed the sending unit.  No luck!  We replaced the oil pump and since we were in there any way , we changed the timing chain.  The pressure is better but still not where is was.  What next?

Answer
Hello Paula

It is also possible that there is a blockage in the oil injectors in the valve assembly. i have seen this happen many times. Ususally it is with conventional oil but also with synthetic. If you take the valve covers off and check the oil injectors there, you may even be able to clean them from this location. If the blockage is further down, pipe cleaners can sometimes do the trick, but you may need to use a degreasing cleaner and a high pressure sprayer. This will likely return the pressure to normal since there really isn't anything else it could be since you replaced all of the moving parts already.

If you relying on a guage on the dash only to check oil pressure, it is possible that the sensor or guage is bad.