1998 BMW 316i - Water leaking from underneath

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Fri 21 Jun 2013 22:28
1998 BMW 316i - Water leaking from underneath - Templarcrusader
Hi all wonder if I could have a few pointers please, I will take to a garage next week but just after some advice before.

This eve I noticed water dripping from underneath I have an inkling about AC but worried about coolant pipe.

It's definitely water it's clear and tasteless but why is it leaking.

The car drives faultless however a few weeks ago I had the AC on for about 45 min / hour and the temp gauge nudged a tad to the right, soon as I turned AC off it went back to centre. I once had a car that did the same.

Any advice would be great & really appreciated

Thanks in advance
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Fri 21 Jun 2013 22:56
1998 BMW 316i - Water leaking from underneath - galileo

Most probably condensation from the cold piping of the air con, especially common in warm, humid weather. I had puddles under a hired full-size car in North Carolina one Agust when it was 90F even at night.

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Fri 21 Jun 2013 22:59
1998 BMW 316i - Water leaking from underneath - Collos25

If its clear and tasteless then its not coolant more than likely from the AC.

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Fri 21 Jun 2013 23:27
1998 BMW 316i - Water leaking from underneath - Templarcrusader
Thanks for the replies so far I believed it was as also he water was quite cool whilst the pipes underneath were pretty hot after driving.

What damage is an AC leak going to cause the engine?
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Fri 21 Jun 2013 23:40
1998 BMW 316i - Water leaking from underneath - elekie&a/c doctor

The condensate water produced by the a/con is draining from the aircon evaporator/heater box and not leaking from the engine cooling system.This is perfectly normal and nothing to worry about.If this an E46 model,then make sure single electric cooling fan is working correctly.If this is an E36 model,then this will have an engine driven fan with a viscous coupling and also an auxilliary electric fan at the front of the rad.Both need to be in correct working order to maintain the cooling of the engine and a/c rads.With the a/c switched on ,the engine is put under extra load,so a slight increase in temperature may occur.hth

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Sat 22 Jun 2013 10:35
1998 BMW 316i - Water leaking from underneath - jc2

Also the A/C radiator is frequently fitted immediately in front of a car's normal radiator and if the A/C is operating,it will dump heat into the airstream going thro' the rad.and the coolant teperature will increase slightly.

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Sat 22 Jun 2013 11:21
1998 BMW 316i - Water leaking from underneath - Cyd
a few weeks ago I had the AC on for about 45 min / hour and the temp gauge nudged a tad to the right, soon as I turned AC off it went back to centre.

I wouldn't expect that during driving, unless you are in a hot climate - where are you?

The water dripping from the underside when ac is used is simply the condensate drain for the evaporator. There'll be a note about that in the cars handbook. Quite normal.

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