Low oil pressure at idle?

[PlayingWithTBI]

Here's where we were discussing how to pull trouble codes using the "paperclip trick"

Low power

I have a 1994 k1500 with the 5.7 TBI, a lot of other gmt400 trucks I have driven have quite a bit of git up n go, mine does not. I've replaced the plugs and wires, headers and 3" pipe through dual cherry bombs. Could it be the O2 sensor? TBI injectors maybe? How would I go about testing those?

www.gmt400.com

 

[PlayingWithTBI]

Dies when you stomp it? Needs a tune change.

^^^This. I would check your fuel pressure too.

 

[351FUN]

You've gone through the effort of an engine swap and added a sniper, and you're still using factory gauges?? You can't trust those even on a stock engine, they weren't even right 30 years ago and they're definitely not now. I still have my factory oil pressure gauge hooked up and it reads 15psi lower than actual. You need a real gauge to see if there even is a problem.

 

[Erik the Awful]

I'd check the oil pressure separately. The needle suddenly falling to zero and coming back up sounds like a wiring issue. As far as idling at 20 psi, that's pretty normal.

 

[SUBURBAN5]

What distributor did you install In the 383?

 

[azmikep]

I’ve got about 15-20 psi at idle. Brand new motor. Was worries about oil pump screen or kink on oil tube during assembly. Runs fine good pressure on gas so I know guage works. Following

 

[89RCLB]

Thoughts please...
1989 K1500 stock 350 TBI. At full operating temperature it runs right at 12 PSI at idle with a mechanical gauge connected. It's low enough to trigger the "check gauges" light.
Still acceptable pressure? Engine has right at 160K miles. Don't hear any odd noises coming from the engine and it seems to run fine.

Thanks in advance for any input.

 

[PlayingWithTBI]

At full operating temperature it runs right at 12 PSI at idle with a mechanical gauge connected. It's low enough to trigger the "check gauges" light.
Still acceptable pressure?

That's OK. IIRC the check gauges light will come on if it sees <10 PSI. What weight oil are you running? Maybe jump up to something like 10w-40?

 

[89RCLB]

It's got 5w-30 in it right now. Definitely thought about going to 10w-40.

Thanks for the response!