no oil pressure in my 355

Yep, you got it. Bad sender. Happened to me (believe it or not) on the way to the dealer for a tech inspection for a day at the track. Gauge was reading way way high when the day before it was reading normal.

I didn't have the same day after as you as I just let the dealer check it out since I was already there. Diagnosis...bad sender. Dealer didn't have a new one in stock but found a good used one for $70. (new are around $125 or so). I bought a new spare (found on eBay) for $75 so now I have a backup just in case. The sender is made by VDO so you could probably source one from a VDO dealer for a lot less than the boxed Ferrari part. Looking at the sender, there is VDO stamped on the case and it has 2 contact / connectors. One contact is marked G and the other is marked WK. On the base it says 10 bar on one of the flats of the hex. On another flat is stamped: 0.75 +/- 0.75, on another flat is stamped 10.00. And on one flat (what appears to be the VDO part number) is 30/122

Hope these numbers find you a reasonably priced replacement.

I am somewhat familiar with VDO senders, not as much so as what sender the F355 has. The sender may have a built in pressure switch that operates independantly of the gauge readout (why there are 2 contacts on the sender). On a Lancia (my other "Fiat") I have there is a seperate pressure sender and a seperate pressure switch.


Jeff Davison

 

The Oil Pressure sender near the oil filter is a dual unit....one of those two wires is the on/off switch for the idiot light, and the other wire is for the gage. The common or ground is the housing itself.

But before you go buy a new sender (about $150) check that the wires on the gage in the cluster are tight...I had the same proble....bought a new sender....nothing changes....and then found the little nots on the gage terminal loose and that fixed it....sold the new sender on eBay for $60.....Shi!@#$%^&*.

Hope it solves your problem.

 

That was me who bought the sender!



Jeff

 

Right - this oil pressure sender fails *all* the time on the older Porsches. On the 911 engine, there are indeed two senders (one for the gauge and one for the light).

If you think you're out of oil pressure, you should definitely pull over and not drive the car - it's not worth the risk. Driving without oil would be like living without blood - it can't be done for more than a few seconds...

-Wayne

 

There must be someone who makes a sending unit that would work with the present gauge. Does anyone know an after market gauge and sending unit that we can replace these faulty units. I have not found any 180psi units only 100psi. How about the race guys here?

 

Common 355 problem. Check wiring, then sender, then gauge. Mine is also erratic.

 

I'm having similar problem... first oil pressure was zero no light. Next water temp was reading zero and would occasionally work then drop back to zero..wonder why I would get to gauges failing at the same time? I asked the guy at Ferrparts he says most people that call get both

 

Just remember guys that the senders in your cars were built almost 20 years ago. It's real common for a mass produced part to all fail around the same time. You can expect a new sender to last another 20 years.

The gauges fail mostly to loose wiring or ground fasteners that back out after years of bouncing around, Its usually an easy, cheap repair if diagnosed correctly.

 

going to pull the dash apart tomorrow. I believe you are right not sure I will be able to spot the problem...

 

Use a good electrical connector cleaner, available in an aerosol can at any parts store. clean the connectors. Check the wires that are on the back of the cluster itself. There are a couple ground that are on the printed circuit board that can come loose. Clean them and tighten it all back up. Good luck!

 

Thanks everything is working right now...