Technical White smoke

[Wima]

When I bought the cabrio a few weeks ago white smoke came out the exhaust which was a positive sign for work I was looking for. Now checking the reason for the smoke I need a compression test after the oil was clear, no bubbles from the brown cooling water and plugs are fine. Attached are fotos of the fuses in the engine bay. Can one of you please tell me which fuse I need to pull to stop the fuel and also what that small plug in front of the cover is for. Thanks in advance.

 

[bugsymike]

Can't tell you about the fuses, but if radiator water brown it is possible the cooling tubes are partially blocked internally given the mileage, so unable to get rid of the heat fully due to poor circulation. Often common on older vehicles and an engine coolant flush to clean sediment from around the engine block may be necessary too. Sometimes not helped by cars in warmer climates not using antifreeze as it is also a corrosion inhibiter.
This can result in a slow coolant leak/seepage from the head gasket, smoke/steam from exhaust on start up and possible a slight misfire at same time.
A normal compression test will not show it up and sometimes even one of the "head gasket sniffer" tools may not either.
I have found a "leak test" involving compressed air is more reliable although time consuming and needs the right equipment, but fairly conclusive when you see the water start to rise in the header tank when testing that cylinder.

 

[Wima]

Thanks for the reply.

 

[GrandePunto PL]

1. White smoke from the exhaust? https://www.fiatforum.com/guides/head-gasket-replacement-diy-resurfacing.700/
2. Fuses: https://staff.planet.ee/punto/El_skeem.pdf
3. Connector could be an "OBD1" diagnostic port (3-pin). There are adapters "3-pin Fiat to OBD2".

 

[Wima]

Thanks for your information. I did the compression test yesterday. Cyl 3 dry 50, wet 80 psi. So work as I wanted and will dismantle the head.