salimlt1luv

new problem arose, no oil pressure...When I took on test drive it spuuterred and ran real rough. Initially oil pressure would rise to about only 20psi!!, I realized a hose from the cover to the thottle body and another hose wasnt fastened. I ran it again and when driving at speed it rose to about 40psi, but when I came to stop at intersection or stop sign it would drop to about 20, and then down to ZEROpsi and my check gauge light came on. I managed to slowly make my way back home as engine seemed low on pick up. It also wanted to cut off in reverse when I backed into the garage... Please help... what could it be that is making it loose pressure when I come to a stop or am not accelerating? All I did was change the oil, could anyone tell me where the sensor or sending sensor is for the oil pump?

pizzi-man

Is the motor making noise like there is no oil? Did you check the dip stick and make sure it was full? When you changed your oil, did you notice any thing differant in the old oil? What oil did you use in the change? I had a similar problem and I used Kendall SAE 40 High Performance and brought the oil pressure right back up.

Injuneer

Using a single weight oil, particularly one that heavy, is no good for the engine. It will circulate very poorly on cold start, and that's where most of the engine wear occurs. Use a multi-viscosity oil like a 10W-40.... acts like a 10-weight oil on cold start, with good circualtion. Acts like a 40-weight oil at normal engine operating tmeperatures. While pressure may increase due to the thicker oil, it does not mean you have improved the engine lubrication. Low pressure generally means excessive bearing wear, and using a thicker oil is just a band-aid.

salimlt1luv

thanks everyone... well I came to realize I have to use a heavier weight oil...I was recommended to go to a 20w50 and that should take care of the problem.. I already had the oil pump checked and its in good condition (high volume).. Has anyone had any experience with 20w50? I live in Florida so I don't have too much worry about outside cold temps. I just never used anything more than 10w40.

salimlt1luv

I also changed the oil pressure sensor( using shbox pics...thanks shoebox!!!) I was able to lay atop the engine, find the little ..... and replace it.. I will spare you how in blindly taking it off by hand I broke the housing off and had to use that special tool to get it completely off! So now to change the oil and get my Z on the road again.....

JAKEJR

I've used Valvoline VR1 Racing Oil, 20W50 in a blue-printed 415 L98 engine.

Corvette Action Center did research on this oil issue which was primarily directed at finding the cause of so many flat tappet cam failures.

One of their findings was that VR1 has the ZDDP additives that are now much reduced in other oils. It's one of the oils they recommend. The full report is on their site.

Jake

West Point ROCKS!

salimlt1luv

thanks jakekr
That's what was recommended to me as well- Valvo apprs to be the avenue I'll try. Are there any other options