After my engine warms up and you come to a stop and idle the oil pressure goes down and the check quages light comes on.Ive replace the sending unit does anyone know whats going on with this....

 

Stop driving your car, drop your oil pan, and put your oil pump pickup back in your oil pump, and SECURE it (bolt it, weld it, braze it) somehow.

Failure to do so will result in everyone's favorite noise, a spun bearing knock. Ask me how I know this

 

Thanks for the info those jack A$$s at the dealership said drive your car around and see what happens. Ill drop the pan tomorrow and take a look. Thanks

 

Have you swapped the cam ? It could be the cam bearing or weared main/rod bearings. I had the same problem 5 k. miles after hotcam install and it was due to cam bearings which probably were hurt during the cam swap. Hopefully it's just pickup, although I guess then you should have problems also during the high revs ?

 

I also think that Spinner might be a little quick to say pickup.

I would lean more towards a bearing problem, probably rod or cam bearings. I know my heads/cam/blower 5.0 had the oil presure drop at idle when warm and thats what it was.

-James

 

I totally agree with Spinner..... I had the same problem and changed the whole pump before it did any damage.... search the boards... it's happened to people before and if it's not fixed you'll regret it...

 

By drop do you mean all the way to 0 where your check gauges light comes on? With the pickup falling off... it happens when you brake especially if you brake hard... Pepboys wanted $1100 for the work and then a local speed shop did it for $400 which included new melling pump and oil and all that so I had them do it. $400 to me was better then a rebuild..

 

Oil pressure will be lower at idle. You need to specify what the pressure is.

 

Aye, the check guage light could just be going bad. If you're getting 15psi, that's still fine, but lower than normal. What's your pressure when driving? Normally LT1's run around 20ish warm idle, 40ish cruise, 45-50+ WOT.

Jason

 

Not to point out the obvious, but did you check your oil levels? Low oil can register low pressure...

 

The oil pressure doesnt go all the way to zero but just above it. It dips way down into the orange on the oil pressure guage, And yes I did check the oil for you wise guys out there.

 

isnt it like 6-10 psi for every 1k rpm?

 

Thats true but that is after the base 20 idle psi.

 

The factory manual says 6 psi is the minimum oil pressure at idle. Of course, it's better to have it higher than that.

 

Wow, 6psi, i would shut my car down if it was that low, i think i read in the lingenfelter SB book that idle should be around 20 and beyond that the oil pressure should be 10 psi for every 1000 rpm's. So 60 psi at 6k rpm's. Thats on the safe side probably but he knew what he was talking about.