Slow warm up / running too cold ?

[pflowers]

Hi Guys,

My 2003 s3 has developed a strange fault. It takes ages for the engine to warm up, I can drive for 3-4 miles before the gauge will even move off the stop, it takes probably 5-6 miles for the engine to completly warm up.

When driven normally once warm the guage stays bang in the middle, however on a few occasions if you were say coasting down a long hill or down a long motorway slip road, the gauge sometimes starts to drop down towards cold again

Its as though the cooling system is being too efficient.

The car runs and performs perfectly fine apart from this, perhaps this is normal? /ubbthreads/images/graemlins/confused.gif

 

[imported_monkeytrousers]

My gauge doesn't reach the middle until about 5 miles so that doesn't sound so bad to me. Probably 2-3 miles before it moves off cold.

Don't have the problem with going down hill though - weird. What do you mean "coasting" do you mean "not in gear"?

 

[Kevint]

The warm up time sounds about right for normal driving.

As for the gauge going back down... does it drop to say about 80 then come back up later or is it all over the place?

My gauge has been dropping to about 80 on gentle motorway trips with the recent cold weather - I've assumed it's the thermostat on the way out coupled with good cooling (motorway speed and very cold weather) with light engine load (so not producing much heat).

Kev.

 

[pflowers]

Hi, thanks for that, when I say coasting I mean in gear foot off throttle. We have got a fairly long downhill stretch of 30 mph limit near to my home ( about 1 mile ) I came home tonight after a 200 + mile motorway trip and coasted down this road as normal, the gauge went down to under the 'quarter' warm mark, then as I powered back on up the other side it slowly warmed back up again.

Also it seems to cool down very quick, leave it for say 15 minutes after a long run and start it up again and the gauge is almost down on cold. Any other car I have owned would stay fully 'warm' for at least 30 mins or longer.

Not particularly bothered as it runs fine and under normal conditions it stays bang in the middle. Just interested in the cause.

 

[god_thats_quick]

I've been staying off boost and warming my car up / cooling it down very carefully since I had engine troubles last year.

I can probably go about 5 miles before the water has got to 90c then I leave it a bit longer before even thinking about accelerating hard, I would also say this is perfectly normal.

WIth regards to the temp dropping - my car never moves of 90 once it's there even on slow motorway driving below zero or after thrashing the nuts off it for 10 mins.

 

[Kevint]

[ QUOTE ]
I've been staying off boost and warming my car up / cooling it down very carefully since I had engine troubles last year.

I can probably go about 5 miles before the water has got to 90c then I leave it a bit longer before even thinking about accelerating hard, I would also say this is perfectly normal.

[/ QUOTE ]

That's a good move. I have an oil temp gauge and when the water hits 90 the oil has not even moved off the rest pin, maybe another couple of miles for it to come upto temp.

[ QUOTE ]
WIth regards to the temp dropping - my car never moves of 90 once it's there even on slow motorway driving below zero or after thrashing the nuts off it for 10 mins.

[/ QUOTE ]

Mine never used to either - should stay ay 90 all the time.

Kev.

 

[pflowers]

I reckon my thermostat is stuck open !?

 

[imported_monkeytrousers]

You must have something wrong with the thermostat or gauge. There's no way a fully warmed up car would genuinely drop temperature like that.

 

[pflowers]

I am sure the gauge is fine as it sits bang in the middle under normal driving and goes up to warm smoothly.

Is the thermostat an easy job on the 1.8t ? Presumably they are cheap to buy.

 

[god_thats_quick]

On this subject does anyone know how easy it is to fit an oil temp sensor to an S3 as it's been bugging me for a while that it doesn't have one?

 

[Kevint]

You can get enhanced DIS which will give you that information, I did enquire as to cost, and it wasn't all that bad, but I can't remember, sorry.

Kev.

EDIT: Just found the response to my enquiry email...

[ QUOTE ]
Hi Kevin

This is a plug and play kit. Price is $690.00AUD incl freight.

You must have Audi factory radio if not requires connection through the
instrument cluster. Comes with extensive installation manual.

Regards,
Walter D'Addario
Ph 0412 196 193
Advanced Motorsport Tuning
ClubVAG Forum


[/ QUOTE ]

You'll need to look the exchange rate up though.

 

[god_thats_quick]

That's not too bad cost wise, it's more the sensor than anything else though as I'd want a gauge the same as my boost gauge - I just don't really want to have to drill into anything - or do anything else that can't be removed if that makes sense.

 

[darnich]

Ok this one looks cool,no drilling or anything just replaces the stock oil drain plug, and here is the link:

GReddy Oil Temperature Adapters

HTH

 

[benk]

Could the original problem in this thread be a failing water pump?

 

[pflowers]

[ QUOTE ]
Could the original problem in this thread be a failing water pump?

[/ QUOTE ]

I hope not ! /ubbthreads/images/graemlins/shocked.gif Could it be ? /ubbthreads/images/graemlins/confused.gif

 

[benk]

Not sure, but I know there was a thread not that long ago (in this forum) where guage was playing up, and people were suggesting water pump, etc.

This was the thread I was thinking of:
http://www.audi-sport.net/ubbthreads/sho...true#Post351603

In that example, temp went up, so I'm probably wrong about water pump. That would suggest that thermostat is located so it detects hot water, off the engine even if pump has failed, but radiator could remain cold as pump not circulating that hot water.
Maybe it's just your thermostat playing up?

 

[HTC]

I had this exact problem last year. I changed my thermostat which fixed the prob.

Temp now sits at a constant 90 after warmup.

Its the cheapest option, so you might as well try it before getting more involved.

 

[god_thats_quick]

[ QUOTE ]
Ok this one looks cool,no drilling or anything just replaces the stock oil drain plug, and here is the link:

GReddy Oil Temperature Adapters

HTH

[/ QUOTE ]

That would be just the sort of thing except I don't think any of them fit... I can't remember off the top of my head but does anyone know what thread the drain plug has on an S3?

 

[Ess_Three]

Hmm...interesting...

Has anyone looked at how low the drain point is on the sump on a 1.8T?

My sump had a flat buffed on the lip just below the drain point where the sump had been 'catching' the road surface on some mental yumps...and that was with Bilstein dampers and stronger springs.

You add a sensor through the drain plug and you are in danger of having an even lower (and less strong) think hanging below the engine ready to be ripped off if you get a little carried away on the backroads...

I can't imagine the engine would last too long if the temperature probe was ripped out...allowing all the life preserving oil to drain out!

Just a thought...

Also, wouldn't the sensor wires get twisted badly whenever you took the sump plug out, leading eventually to failure?

If I were to install a stand alone temperature probe into a 1.8T sump, Id have it welded into the side of the sump, well out of the way of the road below...

 

[god_thats_quick]

[ QUOTE ]

Hmm...interesting...

Has anyone looked at how low the drain point is on the sump on a 1.8T?

My sump had a flat buffed on the lip just below the drain point where the sump had been 'catching' the road surface on some mental yumps...and that was with Bilstein dampers and stronger springs.

You add a sensor through the drain plug and you are in danger of having an even lower (and less strong) think hanging below the engine ready to be ripped off if you get a little carried away on the backroads...

I can't imagine the engine would last too long if the temperature probe was ripped out...allowing all the life preserving oil to drain out!

Just a thought...

Also, wouldn't the sensor wires get twisted badly whenever you took the sump plug out, leading eventually to failure?

If I were to install a stand alone temperature probe into a 1.8T sump, Id have it welded into the side of the sump, well out of the way of the road below...

[/ QUOTE ]

I had been thinking that, but was wondering if there would be more of a bolt on solution anywhere, something like one of the oil feed pipes with an adaptor or something, I guess if I want a gauge it's going to be hard work.

 

[max9650]

Bumping this rather then making a new thread, I've got the same problem, about 10 miles to warm up and if cruising then the temp will drop to about 70-80. Had the thermostat changed today but no improvement :/ ? Thanks all

 

[mark_S3]

Bumping this rather then making a new thread, I've got the same problem, about 10 miles to warm up and if cruising then the temp will drop to about 70-80. Had the thermostat changed today but no improvement :/ ? Thanks all

Might be worth changing the Coolant Temperature Sensor.
Not sure on price but they aren't expensive and are easy to replace.

Do a search on here for Coolant Temperature Sensor... I'm sure you'll find the answer on part number, fitting guide and information.