oil problems

[BuickNick]

After the car has warmed up and after some higher rpm driving - when I come to a complete stop the oil pressure will go from the middle of the gauge down all the way. ANY increase in RPM and it goes right back up. Even just shifting from drive to neutrel will make it go back up. If i drive around and keep the engine rpm under like 3k it wouldn't do really do it, and after a highway run it will do it worse.
I just changed the filter, same deal. Oil level is full, 10-30 oil, looks good. Sender unit seems to work.
Anyone expeirence this?
I'm thinking the oil pump is worn, but reaaaaly don't want to change it in this weather. I've got a overhual planned for summer time, so I think I'm gonna try running some 15-40 till then. but wondering if this could be a simpler problem I'm not thinking of...

I did just do the water pump, but I don't really see how that could effect it.

Nick

 

[bill302]

YOU COULD USE SOME THICKER OILS OR ADDITIVES TO INCREASE OIL PRESSURE. BUT IT WOULD NOT FIX THE PROBLEM INSTEAD OF MASKING IT YOU WILL DO MORE DAMAGE IT THE LONG RUN. IT MIGHT NOT EVEN BE THE OIL PUMP IT COULD BE WORN BEARINGS ECT... MY RECOMMENDATION IS TO REBUILD.

 

[sdc13]

check the plug that attaches to the sender. Mine comes loose now and again. The gauge would drop all the way down when I goit on the gas. Kinda freaked me out at first...

 

[Black95GTS]

YOU COULD USE SOME THICKER OILS OR ADDITIVES TO INCREASE OIL PRESSURE. BUT IT WOULD FIX THE PROBLEM INSTEAD OF MASKING IT YOU WILL DO MORE DAMAGE IT THE LONG RUN. IT MIGHT NOT EVEN BE THE OIL PUMP IT COULD BE WORN BEARINGS ECT... MY RECOMMENDATION IS TO REBUILD.

Rebuild the engine cause of wierd oil pressure gauge behavior? Thats crazy talk. Thicker oils? I wouldn't run thicker oils in the winter if I were you.

Anyway, our stock oil sending units are notorious for crapping out, I've replaced mine and I know I'm not the only one. I would check or replace the oil sending unit first.

I know on my 2001 F150 that if its really cold out I need to blip the throttle to get the oil guage to "read" the sender when I start it up.

Adam

 

[BuickNick]

the sender wire is hooked up good. I'm gonna pick up a new sender tonite when I go into the part time job. If that doesn't do it I'm gonna try the thicker oil.
I just need this to last till the beginning of summer. thats the complete O'haul time.
I don't have time to be toying with this now

 

[bill302]

Rebuild the engine cause of wierd oil pressure gauge behavior? Thats crazy talk. Thicker oils? I wouldn't run thicker oils in the winter if I were you.

Anyway, our stock oil sending units are notorious for crapping out, I've replaced mine and I know I'm not the only one. I would check or replace the oil sending unit first.

I know on my 2001 F150 that if its really cold out I need to blip the throttle to get the oil guage to "read" the sender when I start it up.

Adam

oh o.k. i thought when buicknick said,"Sender unit seems to work" i thought he checked it" and i thought he determined the problem was worn oil pump and he was looking for a quick fix to hold him over till rebuild. thanks for pointing this out black95GTS. with that said heres some more info.

1. to test oil pressure switch, open hood and locate the switch.

2.disconnect the wire from the switch attach one end of a jumper wire to the terminal on the end of the wire ,then touch the other end of the jumper wire to a good engine ground (any bare metal surface) have an assistant observe the instrument guage cluster while you do this and tell you if the low oil warning lamp illuminates or not: the low oil lamp should illuminate if it does replace switch with new one.

3. if lamp does not illuminate, before jumping to a conclusion try a different area for grounding the jumper wire on the engine.if lamp still does not illuminate,touch wire to negative battery post. if lamp illuminates the problem lies in engine not being properly grounded. if lamp still does'nt illuminate connect the original wire to the oil pressure switch. while sitting in the vehicle,turn the ignition switch to the on position without actually starting the engine.observe the other lights on the instrument cluster.if all the other lights illuminate when turning the ignition switch on,the oil pressure switch is defective and must be replaced. if none of the other lights illuminate,there is a problem with power supply to the instrument cluster and guages.

 

[BuickNick]

thanks for all the responses
Bill, good info there. But it has an actual gauge not just the light. I don't think the stock gauge is good for much tho. The thing is that if the sender is bad, it is intermittent. If I was gonna test it I'd just pull it out, bring it to work, and check the resistance change with pressure (i work at a place that makes pressure sensors, lol)
But since a new sender was $8, I'll find out if the old one is bad when I put the new one in this weekend, lol