Vectra A problem

[Alex74]

Hello everyone,sorry for my poor English language.
I have a Vectra A 16SV '91 and recently my check engine light came on.
I read the codes (by switching the A and B contacts with the wire on the jack and counting the flashing of the check engine lamp).
I got code 46 - here's a picture from the autodata.



My Vectra has nothing in the cabin to show the oil temperature, the oil light normally turns on when I turn on the ignition and turns off when I turn on the car.
On the engine block I found that oil temperature sensor (part number is GM 90276471) it is connected to the cable but I was unable to track where that cable goes.







Does anyone know if this sensor is malfunctioning or something else?
A new sensor cannot be found here in our country, and a used one can hardly be found.
Any advice is welcome.
Thanks to everyone in advance.

[Robsey]

Code 46 does identify a defective oil temperature sensor.

The best way to check it, is to test the resistance across the two pins of the sensor with a digital test meter set to the ohms / resistance scale.

If the resistance value seems correct for the ambient temperature, then it could be a dirty or loose connector or damaged wiring.

The values should be as follows:-
0°c = 3150 ohms
10°c = 2200 ohms
20°c = 1210 ohms
30°c = 832 ohms
40°c = 585 ohms
50°c = 419 ohms
60°c = 307 ohms
70°c = 228 ohms
80°c = 169 ohms
90°c = 127 ohms
100°c = 98 ohms.

If you wish to test the cable, you could short the pins in the connector of the loom with a resistor of about 220 ohms.
This would tell the engine ECU that the oil is at normal running temperature.
And the engine light should go off.
If the light does not go off, it may be a faulty cable, connector or the ECU itself.

I looked online using "vauxhall 90276471".
I was able to find several sensors available from ebay vendors and some UK parts suppliers.
Do not buy from German sellers, as they always ask very high prices.

- I have to admit, that I was not aware that any of the engines had an oil temperature sensor.
Haynes does not mention it either.
I am sure in Haynes, sensor P24 for the 1991 16SV engine is an automatic transmission fluid temperature sensor.

Every day is a school day. Even for an old toad like me

Regards,
Rob

[Alex74]

Thank you for your help.
I just took off the sensor again and measured the ohms, it shows me 15.6 ohms. The outside temperature was between 10 and 15 degrees Celsius.



Does that mean the sensor died?
When I connected the sensor to the buzzer on the digital test meter it buzzes, it means that the pins are in the connection, I don't know if that's how it should be?



I sprayed the sensor a bit with the WD-40 and put a copper washer (which was not under the sensor before) and then the check engine light went out.





I reconnected the pins and read the errors and did not show them, I was just glad that it was until when I turned on the car he turned on the check engine light again, I read the codes again and again the same code 46.
Unfortunately, I don't have a resistor of about 220 ohms, only when I go somewhere in the city to look if there is something to buy.

As for the purchase of sensors from Ebay - the problem is that they will not be sent from England to Serbia, and they are quite expensive in your country as well.
I found a used sensor here for 5 euros plus postage.
But I'm not sure if this sensor of mine died or not?

[Robsey]

I think we can confirm it is the sensor.

A faulty loom would give either a high resistance or an open circuit (infinite resistance).

[Alex74]

So I'm buying a sensor?

[Robsey]

I would think so, as the resistance should be close to 1700 ohms at approx 15°c.

15.6 ohms would be close to 150°c.

[Alex74]

Ok,thank you.

[Alex74]

Today I received a new sensor, I paid 10 euros for it.
I turn on the car to drive it out of the garage when it turns off the light (I can't believe it) I go for a ride and see if it will turn on again when nothing is normal, I get annoyed that I bought a new sensor when it doesn't seem to be should.
I went into the garage to park it when the light came on, it was easier for me now.
I change the sensor and drive the car a bit again, everything doesn't turn on normally.
I will follow for a couple of days if I go somewhere with the car to see if anything will happen, I hope that I have fixed the fault.
When I tried a new sensor with the digital test meter(in my room) see that its omage is constantly decreasing, let's say its initial is 800 ohms and then it only decreases 799,798 797 ...
And when I attached it to the buzzer on the digital test meter, it doesn't buzz, so it's not in contact,unlike the old one.

[Robsey]

Hopefully it is fixed.

Sometimes a new part can be faulty.
As an example -
There were a lot of faulty oil pressure senders made for the Vectra-A turbo, Calibra and Frontera-A in the late 90's.

[Alex74]

Date on this sensor is 01-98
old is 06-91 i believe is original from factory because my Vectra is from '91.

[Alex74]

Just to let you know that the fault has been fixed by replacing the sensor.

[Robsey]

Good to hear you got it sorted.