Oil pressure gauge crazy?

[yukonaetahoe]

When im driving the pressure switch is at about almost 40, but when i come to a stop or a red light it dropss to 20, also noticed by just moving the gas pedal slowly it goes up whihc im sure is because there is increased pressure.
But my question came up since this never used to happen it was always at 40, ofcourse give or take a couple lines on take off or stop, but never drop this low. any reason why or would i have to change some sensors or maybe even the oil pump?

 

[blueflamed03]

it will increase and increase with temps and engine RPM's....sounds normal to me.

 

[yukonaetahoe]

it will increase and increase with temps and engine RPM's....sounds normal to me.

Thanks!

 

[grimm]

I posted about this not too long ago. Here's what you should be seeing (or close to anyways):

Cold start : 40-60psi at all times

Fully warmed up idle : 18-22psi

Fully warmed Cruising : 40-45 psi

Fully warmed Under load : 40-60 psi

All are considered acceptible. So if you're within those ranges, you should be quite alright.

 

[RSymons]

My truck (97 tahoe) does the same thing. I never really noticed it in my other trucks, but i guess it s normal.

 

[yukonaetahoe]

I posted about this not too long ago. Here's what you should be seeing (or close to anyways):

Cold start : 40-60psi at all times

Fully warmed up idle : 18-22psi

Fully warmed Cruising : 40-45 psi

Fully warmed Under load : 40-60 psi

All are considered acceptible. So if you're within those ranges, you should be quite alright.

Yeah I'm in the range. Thanks man I'm glad I asked, or I would of spent money and got same results.

 

[grimm]

No problem man, glad to help. Noticed you're from the bay too, maybe I'll see your truck around, haha.

 

[biggauges85]

i have the same problem he thinks he had but mine really exists. and i was about to post this but i guess it's just luck.

anyways, my oil pressure does drop when i brake. but also when my transmission shifts gears. and when i put change from/to park/drive/reverse/nuetral. and when i first start it up. and when it drops, it drops to zero. even if it is fully warmed up. but when i press the pedal and increase my rpm's my oil pressure levels out and is fine, until i shift or the tranny shifts gears or i brake. and the oil pressure gauge reads zero i have this wierd clicking sound/noise (sounds like a diesel) from somewhere under the hood (can't locate, sounds travels like crazy). but clicking sound goes away when i force my oil pressure level to stabilize.

anyone know what's wrong? i'm really worried because this is my only vehicle which i need to get back and forth to work. any help would be greatly appreciated.

one my coworkers says it's a bad lifter. he said it could also be the fiber timing gear wearing down or the oil pump not working hard enough. i'm a do it yourselfer (spent 4 years as a mechanic, just never learned how to diagnose) and im pretty sure (unless it doesn't involve breaking down the block and heads) i could fix the problem.

once again thanks for any help.

 

[blueflamed03]

biggauge, I'd for sure check to see with another gauge if your zero at idle, if you double check and it indeed is zero at idle, you have issues.

If you have at least 10-12 at idle, it could be sending unit or sensor.

 

[grimm]

Biggauges85 : Like Bluefamed said, check it with an alternate (mechanical ) gauge to be certain. Also, I know it sounds stupid, but I recently posted about this... check your oil levels. Mine was only slightly low and produced the same symptoms. Once I had changed the oil and filled to the proper amount, everything was good to go.