sick of my oil pressure NEED HELP!!!

Well, I just ordered two senders. One is directly for the Ferrari and was $200.00. I also found one on Rock Auto for a 1990's porsche that looks like the same sender. It was $28.00.

The sender that I removed said it was made in Germany. Just so happens that the Porsche version has the same two post connection as well as the 18mm x 1.5 PT fitting. I would be willing to bet they are the same.

I will try the 28.00 version and let you guys know if it works. If not, it was a $28.00 try. I am leaning heavy towards it working because I am sure Ferrari did not make these and the Germany stamp is good indicator where it came from.

 

I got to say that my car displayed the same oil pressure discrepancies and I asked about it 5 years ago. Was told its not a biggie, not to worry. Now I know why.

 

I previously owned a 78 308 GTS and it suddenly started reading very high on the oil pressure gauge. I simply bought a new Veglia sender from Rutlands and it returned to more "normal" pressures I was used to seeing. The senders can definitely go bad.

To the OP: don't your mechanical figures seem a bit high, particularly when hot and at 6k?

What weight oil are you using?

 

This will be a great find if it works...
Keep us posted

 

I am using 5W 40. I think the values are fine. I just think that Ferrari sets these gauges to read a certain way. I could be wrong. I have never had any leaking problems or problems with seals so I am not too concerned.

 

For people searching the forum in the future, it would be nice if you post the resolution in the other thread you started on your oil pressure "problem" instead of just leaving it hanging: http://www.ferrarichat.com/forum/showthread.php?t=360460

Or, you can probably ask a moderator to combine the two threads. Just a suggestion.

Jes

 

I posted a new thread because I did not think everyone would see it in the other thread. I wanted members and new comers to find it easier instead of getting lost in the other thread. This way, if someone searched for oil pressure gauge, the first thing they will see is the warning about the incorrect thread. I did not want anyone trying that NPT fitting and ruining there oil filter housing. If others are like me, they will sometimes do a search and only read the first couple posts.

I see your point and will add the top post here to that thread so there is closure.

 

Well, I figured it out.

If anyone is having concerns about the oil pressure in thier 348 or 355, get a mechanical gauge and test it before you throw money at it.

I have been chasing a low oil pressue issue for weeks and finally broke down and got a mechanical gauge to get a true reading.

Here are the results:

Idle Cold (First five minutes) Elect: 65 Mechanical: 90
Warm Idle: Elect: 30 Mechanical: 60
Hot Idle (20 minutes idling) Elect: 20 Mechanical: 50-55
Give it a rev to 6K Elect: 45-50 Mechanical: 90-100

So, as others have said, use these gauges as a guide because I can now say they are not very accurate, at least mine is not.

One other tip. If you buy a mechanical oil pressure tester, you will need an adapter to thread it in to the oil filter housing. The adapter has to be 18MM x 1.5 thread pitch. The one that comes in the MAC kit looks close but is NPT and will strip the threads on your aluminum oil filter housing.

Hope this helps someone out there

 

At least it reads lower rather than higher.

 

Am in the process of waiting for a new oil pressure sending unit. The factory one was back ordered. So, I ordered a Porsche Unit.

The Porsche unit is the same 18MM X 1.5 thread pitch. It has the same two wire connector for the gauge and the warning light. It is also a VDO just like the one I took off the 348.

While I wait ot try this out, was wondering what others thought about wether this will work.

Seems that the Ferrari uses a 10 bar sender and the Prosche uses a 5 bar. Also, the porcshe is 80 psi where the Ferrari appears to be 110. Seems that most of the VDO senders are set at 0-180ohms.

So, does the 5 bar vs. the 10 bar really matter or are most of these senders the same? Is the only difference the gauge face?

The Porsche unit was $28.00 dollars and the Ferrari one runs around $200.00. I am going to try it either way but am just wondering if anyone else understands the difference.

 

Let's keep the oil pressure/sending unit threads, from the same OP, together.

Two threads merged.

Thanks,

Mike

 

Definitely good to know. Where did find the adapter?

 

I found it at a local parts store. You can also get one on egauges.com. You will need the right NPT female for your gauge to M18 x 1.5 TP male.

Works perfectly.

 

Gotcha. Thanks!

 

Just spoke to VDO technical support about my oil pressure sender. Based on the stampings on my oil pressure sending unit, they told me that the sender I have is 10-180ohms, TEN Bar/150 psi Unit with a dual post set up. One post for the guage and one for the oil light.

So, I ordered a VDO 10-180ohms, 10 bar/150psi dual post sender from EGauges.com. It is the same exact specs as the Ferrari sender except it has a 1/8 NPT thread which egauges offers the adapter to fit the ferrari. The Sender is Part#: 360-025 and the adapter is 1/8 NPT female x M18 X 1.5 male (Part# R7965)

The sender was $26.95 and the adapter was $7.60. That is a total of $34.55 plus shipping. Even adding second day air the total cost was only $54.00.

The Ferrari sender is $215.00 plus shipping. If this works, that is around $180.00 difference in price.

I will have the sender tomorrow and by 6:00pm EST will let everyone know if it works.
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Look forward to the next update.

 

Well....that sender and the fitting worked perfectly. But, when I hooked it up, I had the same troublesome pressure as the old one so my old sender was not bad after all.

So, I hooked one end of a jumper cable to the sender and one to the frame. PRESTO!! Problem gone. So, I hooked up a new ground from the block to the frame and my pressure is perfect. And, that problem with the pressure dropping when I turned the lights on.....gone. It still drops a HAIR but nothing like before.

So now my cruising pressure at 3000rpm warm is around 75-80 pounds and I have between 35-40pounds at 900rpm idle....PERFECT!!!! Finally.

So....if you need a pressure sender, they can be had for $26.00 not $200.00. And, if you are having trouble with your gauges, add an engine to frame ground.

Hope all this helps and I will add this to the parts interchange sticky.

 

That is very useful information, thanks for sharing the resolution.

 

Nice work! Alfa oil pressure gauges are notorious for the same behavior - I'm going to try the extra ground next time.
Jes

 

Very good info indeed! A link should be posted in the parts interchange sticky thread.

 

Interesting fix. The Motronic ground is on the rear of the right side valve head, near the connectors for the cam position sensor and throttle position potentiometer. You may want to check that connection and make sure it is clean and tight. I went ahead and refreshed the ring connector to the wire harness, just to ensure it was good.

It would be also worth cleaning and checking all the battery connections under the right side engine cover too.

 

Thanks for doing this. Way easier to find and track in the years to come. Much appreciated.

 

Nice find, thanx for the info.

 

Solid bit of intel there. Nice!