Need Help Oil Pressure Drop!

[Kristi]

Driving home from work today, I did my usual 'merge' into traffic using the short entrance ramp. I eased out and then rolled into the throttle hard. For some reason, the car did not shift into second gear, hanging up at the top of first. I lifted immediately, concerned, and resumed normal driving. Shortly thereafter, I leaned on the throttle again to see if I indeed had a problem. This time I was rolling, and the car downshifted to second gear pulled smoothly, and upshifted to third. Boost did not exceed 15 lbs, as I expected. When I lifted, the car immediately stalled. I pulled over onto the shoulder and re-started the car. It fired right up and then promptly stalled. I started the car again with the same result. I started the car a third time, and kept the car running with the throttle. O2's were in the 700's and 800's at idle, but eventually returned to normal. Nothing has changed in the tune-up in the recent past.
I got back on the road and was shocked to see the oil pressure gauge (mechanical) reading about 15 psi lower than normal. At cruise, it is usually about 55 lbs, and 35 lbs or so at idle. Cruise oil pressure is now about 40 lbs, and drops to 15 - 20 at idle.
As soon as I got home, we changed the oil and filter (which had less than 200 miles on them). The oil looked fine, with no metal on the magnetic drain plug. Upon re-start, the oil pressure still reads lower than it did before this adventure.
There appears to be a faint tapping in the right front of the motor. It's difficult to tell, but it seems to be more in the valve cover than the lower engine. Could I have overspun the engine and bent a pushrod, or collapsed a lifter? The sound is very faint at idle, but slightly more noticeable when I move the throttle. Would either of these failures cause the lower oil pressure readings?
The motor is well-built, with good parts, and about 9K miles. I hope that the problem is not in the lower end. Any thoughts?

 

[Outpost]

TTT

 

[blackbuick87]

Hard to diagnose without the engine apart. When the engine was rebuilt did it get a new oil pump? It could be as simple as the oil pickup being partially blocked

The fact that it didnt start could be from getting on it and off quickly, and the IAC couldnt keep up temporarily flooding the engine.

The engine will run without oil pressure, dont think that would cause a stall.

I would probably pull the valve covers, and with the engine running see if you can hear anything. You could pop the rockers off to check the pushrods if you want. Next would be to pull the intake and check for a collapsed lifter or damaged cam lobe

Sorry this is not much help but will need more info to make a good diagnosis
A bent pushrod should not effect oil pressure

 

[Rollin]

First off you need to adjust your T.V. cable one click in should do it. Second pull the drivers side VC and check the rockers for proper oiling meaning they should but producing oil out the tops when running it won't shoot out in streams like a SBC but will be enough for you to tell oil is coming out of them. If no oil is being pumped out of the rockers, what has happened is the the drivers side galley plug has fallen out and your oil is dumping back into the pan. This would drop your pressure 15-20lbs immediately like you've stated. The stall condition could be a number of things. This is hypothetical be maybe the plug got hung in the timing gear and caused a prob with the crank sensor shorting it out intermitantly until it cleared and fell into the pan.

Geoff