Ed30 Temp Gauge Drop When Coasting

[GrayMK5GTI]

Afternoon All,

I collected my Ed30 on saturday and in general its running really well, still feels very tight 

However. . . although it warms up quickly (definetly quicker than my K03 GTI did), and holds 90 degrees on the gauge when driving, if i take my foot off and coast down to a roundabout the water temp gauge drops a little bit - more noticable when coasting from 60mph to a standstill. When I accelerate away again it goes back up to 90 degrees quickly.

I did 200+ miles on the motorway over the weekend and whilst driving it held a solid 90 degrees still.

I've done a quick search, but most thermostat / temp sensor issues were about the car either taking a long time to warm up, or the fans coming on all the time, neither of which are similar to my issue.

For clarity, its got no fault codes, coolant is clean and full, Cambelt & water pump replaced by last owner in 2012.

Any ideas? does this sound normal for an Ed30?

Thanks,

Gray 

[V2 FAN]

Hi Mate

Not noticed any change in temp on mine, it holds a steady 90 until switched off 

[GrayMK5GTI]

Thanks matey!

Is yours an Ed30? I heard they have different thermostats to a GTI. Was hoping to pin it on that 

It's looking like the thermostat is not working 100% right then.

[skard]

I have thermostat coming which I am putting on at the same time as a new timing belt.

The BYD (ED30) has a different stat according to ETKA - 06F121111H same price about £30

[doylebros]

This could be the auxiliary coolant pump running unnecessarily

http://www.ebay.co.uk/itm/VW-GOLF-MK5-GTI-04-09-2-0-TFSI-AUXILLARY-SECONDARY-WATER-PUMP-1K0-965-561-G-/231085460592?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item35cdc44c70

Chassis number dependant part number 1K0 965 561 G - price £136.93 full retail inc vat from the dealers.

Get it scanned to see if any sensors are faulty causing it to run?

[GrayMK5GTI]

^thanks.

I'll try to get some logging done later. I've read on the MK6 GTI forum that's it's quite common fault with those. They are all getting the thermostat replaced.

[V2 FAN]

Thanks matey!

Is yours an Ed30? I heard they have different thermostats to a GTI. Was hoping to pin it on that 

It's looking like the thermostat is not working 100% right then.

Hi mate yes it's an Eddie  was out earlier and checked to confirm but it's certainly a steady Eddie at 90 

[GrayMK5GTI]

Just been out for a drive. Did the little trick with the climate display to get the coolant temp shown in the display. Although the dash gauge was showing 90 degrees, the climate display was showing the coolant at around 74-76 degrees driving around at 30mph. I did a long run on the by-pass and allowed it to coast in gear where the climate dropped down to 70-71 degrees and the gauge dropped by one notch by the time the car had slowed from 80mph to 10mph.

I pulled over and the gauge moved back up to 90 degrees. I let the engine idle until the climate display showed 87 degrees where I could feel the heat on the radiator so the thermostat must have opened. When the climate said 89 degrees, the fan switched on and the temps dropped. During this, the gauge stayed at 90 degrees.

So to summarise, when I'm driving normally it holds 90 degrees on the gauge no problem, but after a long coast in gear from speed, the gauge drops a little. 

[GrayMK5GTI]

Done another load of reserch and i've seen threads on the Briskoda & Audi Forums where others have had the same problem.

Its looking like the thermostat is sticking a bit. Not a serious issue, but something that i'll get round to!

[MichaelR]

Did the little trick with the climate display to get the coolant temp shown in the display.

How do you do that?

[GrayMK5GTI]

Did the little trick with the climate display to get the coolant temp shown in the display.

How do you do that?

See here: http://www.golfmkv.com/forums/showthread.php?t=27

http://www.golfmkv.com/forums/showthread.php?t=9433

Note, 15:0 isn't oil temp. Can't remember what it is though.

[MichaelR]

Thanks mate!

[vRSAlex]

You need a new stat. Having it run low will hurt power and economy. Get it changed sooner rather than later.

[GrayMK5GTI]

^ thanks Alex.

Stat ordered today. Looking forward to fitting this 

We did the climate trick with my mates K03 GTI and that was running about 5 degrees warmer than mine

[GrayMK5GTI]

New stat has solved the problem