My friends truck broke down on the highway, he said it had a loss of power instantly. i went and checked it out, and it had a really bad knock.
i started it and looked in the oil filler and there was no oil squirting up. i put a quart of oil in and the knock went away. the next day i checked it and there was no oil pressure. my buddy said to get some engoine oil flush and it shjould clean out the system. now when i start it there is oilpressure when its ideling but if u give it any gas the pressure drops the all the way. any ideas??
i am going to replace the lifters beacuse the knock wont go away
thanks for the help

The truck is a f-150 1993 . inline six cylinder EFI

Drop the oil pan and check the inlet screen on the oil pump.

First check a manual from Chilton or some manual from the auto store close by.

My F150 V-8 5.8L had the same problem with oil pressure and knock, along with no oil pressure after a while.

The oil screen on the pump pick up in the sump was clooged and restricted.

Engine oil flush will break away more debrie and continue to clog the oil screen.

Stop the engine and sometimes the debrie falls loose, until a suction is applied by the oil pump, once the engine is running again.

thanks alot ill drop the pan 2morrow or once this damn rain up notrh stops. thanks a lot

i have an 1987 ford f-150 with 5.0 v8 (302) when i would start it i would have fine oil pressure but when the motor got warm my pressure would drop to almost nothing. i droped the pan ended up with new oil pump, opil fillter, pick up screen, rod and crank bearings. fixed my oil pressure problem for the most part. ended up about 3 months later my new oil pump broke and bamm knock knock knock it sitting in the driveway waiting on an new motor. lol

i had the same problem once with an '86 inline 6. turns out the screen on the bottom of the oil pump was sticking to the bottom of the pan when it drew pressure. same situation, oil pressure drops from good to nothing quickly.

Had same problem on 1993 F150 straight 6. Had no oil pressure, lifters clattered like a diesel. We replaced the oil pump, rods and main bearing. Put it all back together and had good oil pressure until it warmed up and then the pressure would drop again. Checked the rod and mains again to make sure that they hadn't burnt up and they were still like new. Finally went to the top side and pulled the valve cover and the head was caked with burnt oit and crud. Cleaned that off and put back together and the oil pressure has been good and strong. Still had a knock like a lifter, so we replaced the lifters, rocker arms and fulcrums and put it back together and there is still a knock. So, if you happen to find your knock, feel free to let me know, so maybe I can find mine. LOL. But you might want to check and see if it needs a good cleaning, and I mean with a scraper not a flush. If yours ends up looking like mine did you will know what I mean. But it did fix our oil pressure problem. Good luck

umm only thing that going to fix my knock is an new motor my new oil pump slaped in two and spon my new bearings