Loss of Oil Pressure

[Black Stampede]

Ok guys, I have a problem that I want to get figured out. At the beginning of the season my car would show lots of oil pressure (yes stock gauge) without wavering for about 15 minutes of driving. Then as soon as the motor got warm when I got to a stoplight the needle would quiver and shake at about mid gauge. As soon as I revved it it would go back up and it was all the way up while driving.

So I changed the oil and problem gone. Even when it got warm nothing changed about the pressure, ran great. However, about 1500ish miles into this change it is doing it again. Literally will run perfectly normal at 180 then start doing this crap at 190.

It's one of those things where when you are slowly down for a stoplight and you put the clutch it while braking and the motor almost dies then the rpms come back up. I watched the gauge during this and when I hit the clutch and brake the gauge dropped almost all the way down then immediately went back up to about mid gauge and started quivering. The car will sound like it is going to die during this sometimes.

It has died once when slowing down like this. I thought it may just be the sending unit messing up the gauge, but now that it is actually effecting how it runs I know it isn't. Also, the oil is full. I had an old dodge dakota that would die when slowing down, but the oil would be low when it would do it.

I am going to change the oil today and see what happens, but regardless what is going on here? If it stops again after I change the oil, why is clean oil fixing this issue?

Thanks for any and all help!

 

[Black Stampede]

Also, it does not clatter or make any engine noise at any point.

 

[revhead347]

Weird. I know that the stock gauge doesn't really measure oil pressure, but if it's associated with an inconsistency in the engine, then there is definately an oil pressure issue. How low does the RPM drop when it does this? Is it possible that it's dropping, say below 800 RPM. Could be the oil pump losing too much RPM and dropping below the 6 psi trigger. How old is this engine?

Kurt

 

[Black Stampede]

Weird. I know that the stock gauge doesn't really measure oil pressure, but if it's associated with an inconsistency in the engine, then there is definately an oil pressure issue. How low does the RPM drop when it does this? Is it possible that it's dropping, say below 800 RPM. Could be the oil pump losing too much RPM and dropping below the 6 psi trigger. How old is this engine?

Kurt

I just changed the oil and it is back to normal. What the heck is the deal??

The motor has 90K on it.

 

[rio95]

Crap got in your pan so not surprising. Also you still haven't put an oil pressure gauge on it like I said from day one so I have nothing new to tell you.

 

[Black Stampede]

If it was solely the gauge wavering id be inclined to believe it was gauge issue, but the motor doesnt lie. Why does an oil change complete solve the issue for 1,000 or so miles?

 

[VibrantRedGT]

Get a real gauge. The stock gauge I believe is run off the distributor gear area or some crap. Basically its more of a GUIDE then a GAUGE.

Auto Meter Ultra and they aren't expensive either.

 

[Black Stampede]

I know I need to, but regardless why would clean oil make the engine stop being weird? And keep in mind it was only oil that MAYBE had 1,000 miles on it.

 

[Chern_889]

Sounds like the oil thins out(when hot) and you are losing pressure, could be the oil pump is starting to crap out, or the bearings are going south. When you change the oil, it is fresh enough to maintain good viscosity.

See pictures below for what happened when my stock gauge started to flutter at idle, thought it was just the sender unit as it was still running good, and would come back to full once you got off idle.

all of the main bearings where down to the copper when i took it apart, dont if it was the pump or not.

 

[Black Stampede]

Did it start making any noise when it went or at any other point? Where you beating on it when it went? Details. Thanks for the help!

 

[Chern_889]

no different noises that i can remember, the car had a bad vibration though from the day i bought it until it blew apart that i never did track down. The car still ran good and had good power, but you felt it in your ass.

I was merging onto a freeway and got stuck behind a slow truck, once i could get around him i put it down to WOT in 2nd, redlined it all the way to 6100, shifted to 3rd and made it to about 3500 and after some bangin it was pure silence, creepy feeling. I had to run back about 200yrds to get the balancer and timing chain bits out of the driving lane.

 

[Black Stampede]

no different noises that i can remember, the car had a bad vibration though from the day i bought it until it blew apart that i never did track down. The car still ran good and had good power, but you felt it in your ass.

I was merging onto a freeway and got stuck behind a slow truck, once i could get around him i put it down to WOT in 2nd, redlined it all the way to 6100, shifted to 3rd and made it to about 3500 and after some bangin it was pure silence, creepy feeling. I had to run back about 200yrds to get the balancer and timing chain bits out of the driving lane.

That would be awful! I am not sure what route to take with mine. What is the best plan of attack?