OK so I swapped a 350 into my 92 Camaro and I cant seem to get my oil pressure gauge to work properly.

I tested my oil pressure with a mechanical gauge, and my oil pressure is fine, High Performance motor idling at 60 PSI.

My gauge in the cluster will move up to about 10 PSI with the engine running and bounce up to about 15 with a rev. (Barely out of the redline) Also gauges spaz out when I adjust dimmer switch. could it be a ground issue? anyone have any ideas I could try?

I've tried everything I can think of I'm very technical just looking for some ideas on what it could be or anything else to try.

I'm stumped

I know someone is going to say use aftermarket gauges, but for now im trying to stay with the stock cluster.




I have already:

• Searched the forum (Can't find someone with the same problem)
• Replaced Oil Pressure Sender
• Grounded the wire to make sure it shows zero
• Disconnected the wire to make sure it pegs
• Swapped dash cluster (I have 2 but no guarantee on either being in working condition)

Any and all help is appreciated, Thanks in advance!!

-Ken-

 

You sure you got the right sending unit to go with your gauge? (6-cyl dash vs 8-cyl dash, SU to match)

 

I'm almost positive but I will look into it gonna head to the autoparts store and find out soon

 

60 psi at idle is not right. Maybe at maximum rpm but not at idle. Perhaps if it's stone cold (as in near freezing temps and just started) and a heavy weight oil being used but otherwise an operating temperature Gen 1 SBC will have an idle oil pressure less than 30 psi (in my experiences anyway which are many and varied). Worn engines could have half of that and still be fully functional. That's providing that once the rpms come up, the pressure rises also.
You're on the right track, matching the sender to the factory gauge.

 

Sounds like the wrong sending unit.

The last 2 350's I rebuilt had 60psi at idle cold, once they got to operating temp it was 20-25psi. Thats with 10w-30 oil, and stock Melling oil pumps.

 

It's 60 psi at idle heavy weight oil cold start, I replaced the sending unit again with the 92 camaro stock one, still same deal

 

Been at this all day can't get...I'm going to run a direct wire from sensor to gauge and see what happens...ill keep everyone posted thanks for the help

 

still no luck anyone have any ideas? could it be a ground issue? when I turn my light dimmer switch my gauges spazz

 

Depending on his bearing clearance, 60 at idle, with most aftermarket high volume pumps is typical. mine sits right around that with 150 degree of oil temp. It drops a bit when we can actually get some oil temp into it (190-200 degrees)

To the OP, what weight of oil are you running?? as far as the gauge goes, i never trust factory gauges. Put a decent quality aftermarket gauge in the car and dont worry.

 

The fact that the gauges are affected by moving the dimmer switch tells me that you have a poor connection in either the grounding circuit or the power circuit to the cluster. It's probably being affected by an increase or decrease in voltage to the dash lights. Do you have a wiring diagram for the car. You say you're a savvy. You need to have a good set of wiring diagrams, like the ones available in the Helms Publishing factory service manual electrical diagnosis supplement. Perform a voltage drop test on the power supply circuit with the key on(cluster powered up) and again on the ground circuit. Check connections at the cluster since this is the most common trouble area. Then check connections at the grounding points shown in the diagram.

 

Agreed.
I'm thinking more along the lines of what I see with a good heat soak and perhaps an engine that's not as new.
60 psi stone cold is what I'm seeing on my fresh 350 (Auto Meter electric gauge). Put a few hours into it and get the oil temp past 200 and it's a little different. If I recall, idle pressure is about 35 psi when fully warmed up.