i'm finally getting around to getting my car fully road worthy (it's close). i drove it over to a friends house last weekend which is about 15 miles away. this is about the longest trip the car has had in a LONG time. oil pressure is fine when i start it, but by the time i got to my friend's house the oil pressure was VERY low (near the red on the gauge) when the car was near idle or idling like when i slowed to go around a corner or at a stop sign. once the RPM's rose the oil pressure rose to a safe range. what is causing this? the car runs great other than that.
------------------ 1986 Fiero GT 1992 Chevrolet Beretta GTZ 2000 Chevrolet Blazer ZR2 2004 Saturn Ion '2'
" I guess I've learned that there's more to life than racing, but not much more." -Paul Menard
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12:27 PM
PFF
System Bot
2.5 Member
Posts: 43235 From: Southern MN Registered: May 2007
I can say that owning two SE's with V-6s, the pressure usually starts high when cold and when the engine warms up it will sit at about 20 during idle and up at 40 during normal cruising.
Abe
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01:38 PM
Philphine Member
Posts: 6136 From: louisville,ky. usa Registered: Feb 2000
mine has done that since i changed my sending unit (the old one was keeping my fuel pump on, the sender part was ok). there was no other change at the time and i read sometimes a new sender will do this. so i look at it, but it's been that way for a while now. i can't say i don't worry at all about it, but i've kind of accepted it.
was a new sender part of your repairs? i think i also read that if it is just the sender, getting one for an '88 will work better, but i haven't tried it.
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01:48 PM
jetman Member
Posts: 7803 From: Sterling Heights Mich Registered: Dec 2002
Fiero gauges are famous for being inaccurate, get a real oil pressure gauge on there to find out for sure.
Yes, the oil pressure will drop when warm versus cold, as stated above, that's normal. Wear on engine bearings will cause lower oil pressure too as well as the type of viscosity you're using, length of time between oil changes.
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01:49 PM
gunslinger Member
Posts: 352 From: southland pines,fl Registered: Mar 2008
The main cause of that is the crankshaft bearings is worn and that is what is causing the pressure to drop or fluctuate while idling,eventually you will need a rebuild just use thicker oil with good bearings the pressure should remain constant.
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02:29 PM
2.5 Member
Posts: 43235 From: Southern MN Registered: May 2007
Not in any vehicle I have ever been in. The oil perssure goes up with accelleration. And it will be high when the oil is cold, meaning not at 180 degrees.
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03:25 PM
Francis T Member
Posts: 6620 From: spotsylvania va. usa Registered: Oct 2003
Could be a badly worn out engine, but since it's a lot easier to change oil pres sending units than to plasti gauge bearings, I would go that route first. I had the same issue with my 87GT, even made the idiot lite blink now and then. Changed the sending unit and the oil pres went right up no more idiot lite.
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03:49 PM
fastblack Member
Posts: 3696 From: Riceville, IA Registered: Nov 2003
wow, thanks for all the suggestions guys. think i will try a new sending unit and go from there. i kinda want to replace that gauge and the volt gauge with some aftermarket ones, just still trying to figure out how to fit them in the original spot...thanks again
brian
------------------ 1986 Fiero GT 1992 Chevrolet Beretta GTZ 2000 Chevrolet Blazer ZR2 2004 Saturn Ion '2'
" I guess I've learned that there's more to life than racing, but not much more." -Paul Menard