Low oil pressure after 1.8 swap and new turbo setup
 

Hello guys, I recently swapped a 96 1.8 into my 90 NA:party:, and installed a new turbo setup as well. I kept my oil pressure sender from my 90 and installed it onto the Tee for the new oil feed line for the turbo. One end of the Tee goes into the block, with the pressure sender opposing it straight off the block, and the middle of the Tee facing back runs the oil feed line for the turbo. I originally was going to put the sender parallel to the block but it didn't look like it would fit very well any other way, but now I am wondering if it is giving me a low reading due to the oil feed being before it on the Tee from the block.


When cold starting the car it is at around 10-15psi of pressure on the stock gauge, after warming up however and idling at around 1000rpm it drops to nearly nothing on the gauge:vash:, but jumps up quite rapidly with increasing RPMs. Does this sound like something I should be worried about? Is it a result of the way I set it up? I'm not really sure what to think but I just get a sinking feeling in my gut every time I look at the car and see the oil pressure so low and it definitely worries me. I did try searching for awhile but didn't find anything specific to my question, hopefully someone here will have some insight.

Here is a video showing what its doing.
At the very beginning on the first rev drop you can see the oil pressure gauge flicker before it drops off. About 10 seconds before this before I started the video it was holding the pressure at around 20-30 at idle and then flickered and dropped, came back part way, flickered again and then dropped out. Sound like a bad sender?

Pull the connector off and clean the contacts.

Mounting the sender on the tee like that shouldn't impact the reading.

Where did you get the 96 engine? I assume it's used? Do you have oil pressure numbers from that engine before you bought it? Did you inspect the bearings before installing it?

--Ian

I did take it off and clean them! Didnt help.

Good to know about the T, I second guessed it after I saw the weird pressure readings. I do not have oil pressure numbers from it before, but the bearings looked good, engine only had 80k on it and seems to be in great shape, it runs very well, this oil pressure reading is my only concern.

I would hook a mechanical gauge up and check the oil pressure with it, see what it says. If it agrees I'd start investigating. Probably by hooking the mechanical right to the block and see if the pressure rises (eliminate the tee and turbo feed completely) and if still low you got problems...

The oil sender tend to break internally when they are thightend to hard from the top. The top twist from the bottom and then it breaks internally

I only ever used a wrench on the bottom, never messed with the top. The way it cuts in and out, flickers etc. however makes me believe its the sender. And I hope to God its the sender after all the other work I've done the last couple weeks I don't have time to pull the motor and do an oil pump. I don't have a mechanical oil gauge but I'll see if I can get my hands on one soon.

And you sure there is enough oil in there?

Ground

Yup!

What ground would cause that? They all are fresh and cleanlu mounted.

I believe the sender grounds into the block when you screw it in. So adding the "Tee" for the oil line could affect the ground.

In theory, yes, but the commonly available tees are solid brass and will conduct the ground path just fine. That's how every 95+ FM2 kit out there works.

--Ian

I was just offering an explanation for the ground. I have run several 94 senders with tees of various brass/steel over the years and never had the grounding not work.