'94 Z28 Automatic, 176k miles...currently on its fifth opti (including original)...this latest one was installed for free about one month ago because it replaced another opti that was installed about a year ago, so it was still under warranty...lol

Here's my problem:

Driving it last week for about 15 minutes on the highway during one of the hotter days yet this year (high 80s to low 90s and humid), when I noticed my oil pressure was so low, it was about to touch the red line as I would come to a traffic light stop and idle (in fact, the check gauges light did come on). Had to put the car in neutral to get the oil pressure out of the red when idling....everything seemed normal at the time the oil pressure went low enough to trigger the check gauges light...no unusual sounds from the engine, no knocks, no nothing except the low reading...

Took it to the shop about a week later...they ran their own gauge on the engine and told me I only had 14lbs of pressure cold at idle, and 22 at 2000 RPM, which I found odd, because the day I took it to the shop, the in-dash gauge read 30lbs cold at idle...could my in-dash gauge be that off? And if so, what was it the day it redlined???? Negative pressure???

Anyway, they pretty much refused to investigate the oil pump (original) and insisted my engine was a goner or would be soon enough. The only thing they would recommend would be an engine replacement, which I of course will not do at this point....

My water pump is also starting to go, as I am losing coolant through the weep hole. AND, my engine has some noticeable hesitation while accelerating, leading me to believe that the just installed opti is getting screwed by this leaking water pump....

Oh, and for the last month or so, on a few occasions, I have noticed a fairly loud ticking noise when starting the car first thing in the morning (definitely a tick and not a low end knock)....the tick would always disappear within 1-5 minutes of driving....the shop said this is due to the lack of oil pressure, but I'm not so sure, because I let the car sit for a few days, and didn't get a tick when I started it after sitting....like I said, this tick has only happened a handful of times with really no rhyme or reason to its coming or going....

I was thinking of replacing the water pump IF I can get another free opti since the one that's in there is only a month old and still under warranty.

If I also switch to a thicker grade of oil, what do you think the chances are of being able to drive the car without any major issues for another six months to a year?

 

Sounds like the sending unit is at fault. Those oil pressure readings with a mechanical guage are fine and above spec. I believe hot at idle should be 6-8psi minimum.

 

Will I gain any noticable improvement in oil pressure from moving to a thicker grade of motor oil? What are the risks in doing so?

And is it worth it to spend all that money on a new water pump? I love this car, hardly ever beat on it, it never overheated, and a vast majority of the miles are highway miles (no sit-and-go traffic).

I'm actually a little puzzled that it didn't last longer before the bearings started to go (at least that's what they're telling me is the reason for my low oil pressure, but it seems to be just an educated guess on their part....they see 176k miles and a 15 year old Z28 and pretty much refuse to consider any other reasons, such as oil pump issues or whatnot).

 

https://www.camaroz28.com/forums/sho...sure+acting+up

 

14psi cold idle sounds awfully low to me...

I find it also strange that my in-dash gauge was reading higher than the mechanical gauge...I thought it's usually the other way around when the sending unit goes bad....