Oil Pressure problem at startup?

[70challenger]

here is the problem...

When i go to start my 95 240 (ka24det) there is absolutely no oil pressure reading on my aftermarket oil pressure gauge when i start it up... the gauge will move up to 0 (before starting it sits below the zero mark) and just sit there for a few seconds before it starts registering pressure (sometimes like 5 seconds), then after that everything is normal, and pressures are more than acceptable.

Sometimes if i crank the car over let it fire then turn it off right away, then turn it on a second time the oil pressure pops right up without problem. Anyone know whats going on here, or if this seems really abnormal to anyone else? Should i be worried? I can hear a tapping from the head, but i dont think its the timing chain, i think its from the lack of oil since the second the pressure gauge reads preasure the sound goes away.

Any thoughts on whats going on here or what to look for? The gauge sending unit is mounted where the factory sensor once mounted, its now on a T and the other end feeds my turbo.

[projectRDM]

What kind of gauge is it? A quality unit, especially an electrical gauge should read dead on accurate at all times. You can begin by checking for oil leakage at the T on the block and anywhere from the oil feed line. Also, how long is the oil feed line, and is there a restrictor inline?

[70challenger]

its an autometer gauge, no leaks that i can see so far. The oil feed line is just a straight piece of braided line from the t i metioned to the turbo, its about 3 feet in length.

[70challenger]

any more thoughts on this?

[TheWolf]

why'd you pull the oil for your turbo off where the pressure gauge is instead of the passage out of the block?

[LigouriRd]

The first thing to check is if the autometer sender is properly grounded. The body of the sensor must be connected to ground to work properly. I.e. no teflon tape on the threads. You can also run a wire from the engine block to the body of the sender.

If all of that is ok than you may have a more serious problem with the oiling system. I experienced a similar issue of no pressure at startup, usually after a few seconds the pressure would build and be fine there after...till one time 30 miles away it didn't build pressure at all. I was dumb and though it was merely a bad pressure sender...then the cams siezed to the head. Upon disassembly I found that the oil pressure regulator got stuck open and was not allowing the engine to build pressure. Along with the rebuild I replaced the oil pump cover and reguator. I would at least pull the oil pan and check the connections from the pickup. Should be able to remove the front cover if nessasary.
Be carefull, dont do as Donnie Don't does.

[projectRDM]

why'd you pull the oil for your turbo off where the pressure gauge is instead of the passage out of the block?

There is no such port on a KA.