Mi16 Stop Light

[Edp 67 3 Cars]

Little problem on my 309 mi16. The stop light keeps coming on once the engine is hot. Engine runs without fault, no knocks, bangs and no leaks. Car drives fantastically well and was fully rebuilt by Richard Longman about 15k ago.

 

The fan works and the coolant gauge works perfectly so I have ruled that out.

 

The oil pressure wasn't great so I changed the oil and filter and that didn't do anything. I had a search on here and a post mentioned the oil pump so I removed the pump today and swapped it for a known good one. This has raised the pressure gauge to between the 3rd and 4th lines when cold and between the 1st and 2nd lines when hot. This appears the same as my 205 mi16.

 

The stop light still comes on I guess the next plan of attack is the sender. I know the pressure sender and light are on different wires so surely they can't both be goosed?

 

Anyone have any suggestions?

 

Cheers in advance

[Edp 67 3 Cars]

Anyone?

[Anthony 1,003]

Check the oil pressure with a proper mechanical guage to determine whether it's a genuine oil pressure issue or electrical woes.

 

That said, if the gauge is reading between the 1st and 2nd bar rather than being in or near the red (at idle I'm assuming?) I'd suggest that it's probably the low pressure switch that's faulty. It's the same part as an 8v if you've still got your old one kicking around, or they're not particularly expensive new.

[jackherer 543]

Get a proper gauge like this - http://www.ebay.co.uk/itm/121276745938 - they are pretty cheap and such a useful thing to have in situations like this.

 

Is the standard gauge reading very low when the light comes on? If it is you probably do have low oil pressure but without a proper gauge you are just guessing.

[Edp 67 3 Cars]

Check the oil pressure with a proper mechanical guage to determine whether it's a genuine oil pressure issue or electrical woes.

 

That said, if the gauge is reading between the 1st and 2nd bar rather than being in or near the red (at idle I'm assuming?) I'd suggest that it's probably the low pressure switch that's faulty. It's the same part as an 8v if you've still got your old one kicking around, or they're not particularly expensive new.

 

Thanks for the replies. Pressure sits between 1 and 2 on idle. I'll double check to see if I have my old pressure switch.

 

 

Get a proper gauge like this - http://www.ebay.co.uk/itm/121276745938 - they are pretty cheap and such a useful thing to have in situations like this.

 

Is the standard gauge reading very low when the light comes on? If it is you probably do have low oil pressure but without a proper gauge you are just guessing.

 

I'll get one of these. Thanks.

 

The standard gauge is reading the same as in my 205 mi16, between 3 and 4 when cold, between 1 and 2 when hot as idle. Light comes on once oil temp hits the first line...

[Edp 67 3 Cars]

Ok so to carry this on I have recently swapped

 

-oil

-filter

-pump

-pressure sensor

-spray bars

 

Next up is what Anthony kindly suggested, low pressure switch.

 

Watch this space.

Edited April 27, 2014 by Edp

[Edp 67 3 Cars]

Just to finish this up, I replaced the low oil pressure switch with on of these

 

http://www.ebay.co.uk/itm/PEUGEOT-405-I-SALOON-1-9-SPORT-MI-16-1987-TO-1992-OIL-PRESSURE-SENSOR-SWITCH-SOB-/251339551036?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a8501313c

 

And replaced the pressure switch with a new one and it is now sorted. Cheers guys.