please tell me its just my guage.

[BK_CAULEY]

ok i just got my motor back in my car and now my oil pressure is acting crazy. im not sure if is my pump or the crappy factory guage.

when i crank it up the oil pressure comes up then all of a sudden drops to nothing. if i give it a little gas it jumps right back up and falls right back down at idle. if im cruising it stays up. i think its a guage problem because i dont think oil pressure can just fall flat out to nothing just like that. i figured it would slowly drop if my pump was clogged. but i hae been wrong before.

i cant afford to by an aftermarket guage right now so that method of testing is out of the question. what do you think?

 

[Fett]

I would guess gauge or loose connection. A bad gauge will just go to MAX, and the factory sender/gauge is not that sensitive....so it's rapid movements are not a sign that your actual oil pressure is jumping like that.

First off I would make sure the single connector is firmly on the sending unit post...it could just be loose and the vibration of the engine is "rattling" it causing the connection to jump. If it is firmly connected first unplug it and inspect the post and the connector itself, then follow the wire and make sure you don't have any loose connections elsewhere in the harness. If everything seems to be fine, you might want to replace the sender and see if that solves it. Then hit up a boneyard for a replacement gauge itself.

 

[BK_CAULEY]

thanks fo rt5he reply. thats what i was thinking too

 

[302RollinHard]

I would also double check your grounds as they will give your gauges all kinds of fits.

 

[dtlionsfan]

Go buy an autozone gauge for like $10 and screw it into the sending unit extension,run the line into the car and be sure...............

 

[Mike92GT]

Go buy an autozone gauge for like $10 and screw it into the sending unit extension,run the line into the car and be sure...............

Yeah, you really need to put another guage on it to be sure. The factory guage could very well be correct. Mine did something similar, would drop down to zero, but would shoot back up if I gave it some gas. Turned out that I had almost no oil pressure and a wiped out bottom end.

 

[JETHRO]

Factory gauges are crap. Just an example, when I had my 91 cruising along and turned on my headlights , my temp gauge would go up one notch and back down when I turned them right back off.

 

[93 LX]

Factory gauges are crap. Just an example, when I had my 91 cruising along and turned on my headlights , my temp gauge would go up one notch and back down when I turned them right back off.

The cause of this is that the factory voltage regulator for the gauge panel is bad. I had this problem and replace the regulator and fixed the issue.

 

[Fett]

The cause of this is that the factory voltage regulator for the gauge panel is bad. I had this problem and replace the regulator and fixed the issue.

Where is that located? On the back of the cluster board?

 

[HaynStang]

My volt gauge moves when I turn on the headlights or heater too, even with a 3G. Is that regulator fairly easy to replace?

 

[SVT32VDOHC]

Mine does this too. Two other cars I had did this as well. All 3 cars ran and drove great, no smoke, no oil burning no nothing. It has to be the gauge.

 

[BK_CAULEY]

thanks for all of the replies. and yea i was hoping it was the guage. i just put the motor in and it has low miles and is burning no oil. i was just hoping i didnt let trash get in there somehow and stop my pump up.

 

[93 LX]

the regulator is on the back side of the gauge circuit board

 

[Black1987Stang]

Just to throw something else in here, my friend was having wacky oil pressure readings, not sure exactly how but he had found a crack in his oil pickup tube, he put a new one and it fixed his problem.