S4s oil pressure caerbon gauge or sender or wiring issue

[fflyingdog]

On 26/01/2017 at 09:19, jonwat said:

"I have recently bought a S4s and the oil pressure gauge needle stays (almost?) on 0."

This is normal, it's because the gauge, which is calibrated in Bar, is of too large a scale to measure sensible engine oil pressure.

My old S4s, which was nearly new when I bought it, was the same.

I think Freescan displays the oil pressure on it's dashboard (if not maybe Espritmon) so you could download & install it to confirm what the pressure actually is.  

Mine is exactly the same,the gauge does move but only just ,i'd take more notice of your oil pressure light.

[Giniw]

Still it's really suspicious to me that Lotus put in a gauge which doesn't match the sender?!
In the meantime I have bought a new sender anyway, but I haven't had the time to install or test it yet — I have to finish to replace my timing belt first ^^
I will keep you informed if it's any better!

Edited March 15, 2017 by Giniw

[Giniw]

Hello,

I installed the new sender yesterday. Before I put it in the car I did a quick test at atmospheric pressure, it read around 260 ohms (the rusty one 392). I then put around 3.5 bars (don't know if it's accurate, probably not much) of air into it and measured around 150 ohms. Not extremely close to the gauge curve I posted earlier but at least it moved.

And now it's in the car, and with key on & engine off, the needle rises just a bit, and when it's cold and idling (with unknown oil) it reads almost 4 bars (like 3.8).

On 02/02/2017 at 22:54, Qavion said:

I can't even imagine how hard it will be to remove yours

By the way, the sender was rather easy to remove despite its rustiness. It probably helps that the threaded part is in a oily environment =)

 

Edited April 14, 2017 by Giniw

[Giniw]

(BTW, for those wondering as it's not that easy to access, the spanner size is 16mm.)

 

EDIT: I am surprised the messages wont merge, I think it has already happened before? (and I don't understand why there is a time limit to edit a message?)

Edited April 20, 2017 by Giniw

[Bibs]

Posts only merge if they're made within 15 minutes of each other and no-one else has posted in the meantime. There's a time limit as being able to edit posts is only to correct typos. If you could edit any message in the past you could completely change the conversation. These things aren't done randomly, they are well thought out over 15+ years of running several forums mate.

[Giniw]

All right I understand the reasons, thanks!

On the other hand from my own experience I am not sure people would actually change the content of their message to alter the conversation, but that does makes sense indeed (please note I was not complaining, I was just wondering since I have already wanted to correct a few typos/grammar/etc and I noticed I could not edit my message any more ^^)

[MrDangerUS]

FYI: Really simple and inexpensive solution:

replace whatever you currently have with a VDO gauge and use  Genuine 362-001,  0-80 psi, 10-180 ohms sender.

Both available on eBay for 1/4 of the price of the OEM sender!

BTW, Caerbont gauges are notorious for can failures, which are made of ... yes, plastic. They crack and separate.

In contrast, VDO gauges have metal bodies, glass screen and attractive graphics.

Edited November 7, 2018 by MrDangerUS

[FLOPSHOTGOLF]

On 07/11/2018 at 12:44, MrDangerUS said:

FYI: Really simple and inexpensive solution:

replace whatever you currently have with a VDO gauge and use  Genuine 362-001,  0-80 psi, 10-180 ohms sender.

Both available on eBay for 1/4 of the price of the OEM sender!

BTW, Caerbont gauges are notorious for can failures, which are made of ... yes, plastic. They crack and separate.

In contrast, VDO gauges have metal bodies, glass screen and attractive graphics.

Sorry for bringing up this old thread, but I'm currently fighting the same exact issue as the OP.  Start the car when cold and have about 1.5bars, then as the engine gets warmed up, it drops between 0 and 1 and stays there.  Low oil pressure idiot light never comes on.  But I like this idea of replacing with VDO parts.  I don't mind getting my hands dirty, but I don't know how to do this.  The VDO sender unit has two connectors, whereas the Caerbont sender unit on my 97 Esprit V8 only has the single connector.  So where would I run the other connector to?  And is the VDO gauge plug&play with the factory wiring from the Caerbont gauge?  Sorry for the noob questions but hoping to learn. 

[MrDangerUS]

Before I bought VDO gauge from eBAY, I asked the seller what sender it takes. He had them in stock, so I bought everything at the same time. 180 ohm is most prevalent, but always ask.

The other blade on the sender is for 16psi alarm, casing is your negative. You will need 1/8" NPS to M10x1.0 adapter

[ekwan]

Caerbont electrical gauges require a 10volt stabiliser for its power supply. They don't run off battery voltage???