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ht4100- stop engine-oil pressure light flickers

4K views 4 replies 2 participants last post by  cadillac_al 
#1 ·
-84 coupe deville with the ht4100 motor -
i wanted to replace the oil pump since i was doing the oil pan gasket.
when i installed the primed new one, it wasnt seated right into the block, so when i put it all back together, i started the car. sounded fine and all but after a few minutes, a lifter started ticking and the stop engine-oil pressure light came on. i knew something went wrong with the instalation on the oil pump. i took the pan out and noticed the tube going into the block had too much of a gap in between them and took it off to inspect. i even compared the new pump with the old one by using a drill. both seemed fine. i put the original pump back on the motor (since i knew it was fine before) and the tube seated a lot better giving it a seal. when i put it all back together, a lifter was still ticking for a couple minutes with no oil psi light. the ticking eventually went away and car was good for a few hours.
my brother was pulling it up into the slightly inclined driveway and the "stop engine oil pressure" light flickered. even when it was being put into reverse or drive, the light came on and off. no lights at all when cruising. i tryed it again when it was cold and no lights. im pretty sure it happens when its fully warmed because of the oil thining out.
the only thing i noticed was i had 5 quarts of 10w30 instead of 4 like it says on the dipstick. i will drain it out and only put 4 in there tomorrow and recheck. does anyone know what it might be? i was thinking the pressure switch went bad?
i want to install a oil pressure gauge to see the actual pressure but i dont know where to tap into the block? i was thinking it was right next to the dist. but didnt get a chance to look.
SO WHY IS THE LIGHT FLIKERING? ANY HELP IS VERY MUCH APPRICIATED! THANKS
 
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#2 ·
How many miles? Mine has 187,000 and I put 10-30 synthetic in it a month ago on the last oil change since it was -20 degrees. A week later when the weather warmed up, my oil light is flickering at idle when the engine is very warmed up. Spring is almost here and I am going back to 15-40 very very soon. If you need a good catalytinc converter then 15-40 MAY damage it, so they say, so 10-40 may fit the bill better. My cat was hollowed out by the previous owner so I don't have to worry about it.
 
#3 ·
its got 140,xxx. dont care about cat much but still want ok gas mileage. for weather, its about low 40's. i am just using shell 10w-30. i was going to put in the rotella 15w-40 oil but i wanted to clean out the motor a little first. i changed the oil 3 times in 50 miles or so and the oil is VERY clean now. barely see it in the dipstick when reading it. should i just put the rotella15w40 now and see from there?

i tryed it again and its doing the same thing when its warm. light comes on for a second a soon as i put it into drive. im thinking more like the idle drops a little bit making the oil psi drop below spec or something in that matter. anyone else heard of anything like that? thanks
 
#4 ·
well i realized why the light was coming on... low idle = low oil pressure... so there you go. i put it into reverse and as soon as i cut the steering wheel the idle would drop and light comes on for a second. when the idle would drop below a certain level, the light would come on. does this sound true enough to be the problem?
 
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