error code 128 - water temp sensor & oil temp question

[Zippee]

Whilst out on a run on Saturday my water temp went from running fine (90-95 on the move & 97ish in traffic) to all of a sudden hitting 115, 110, 95 back to 110 etc and the above error code.
I'm assuming this means the temp sensor has all of a sudden gone up the spout, if so where can I get one from? Is there any specific part number & how easy are they to fit? If easy can anyone give me a quick idiots guide to doing so ?

Also my oil temp at idle was hitting high nineties - what sort of temp is danger for oil? It did come back down on the move to 70 odd, but at idle once again quickly went back up.

[FEE 50]

Zippee said:

Whilst out on a run on Saturday my water temp went from running fine (90-95 on the move & 97ish in traffic) to all of a sudden hitting 115, 110, 95 back to 110 etc and the above error code.
I'm assuming this means the temp sensor has all of a sudden gone up the spout, if so where can I get one from? Is there any specific part number & how easy are they to fit? If easy can anyone give me a quick idiots guide to doing so ?

I guess the error code kicked i once it gt above about 110 degrees?
Give the guys at track v road a call. Could be a dodgy sensor, are your fans both functional?
After having mine plugged up to the computer last week I can tell you that the car was reading 97, but the actual temp when plugged into laptop computer (actual correct temp) was 92, so maybe its not as high as you think and it is just a dodgy sensor.

Zippee said:

Also my oil temp at idle was hitting high nineties - what sort of temp is danger for oil? It did come back down on the move to 70 odd, but at idle once again quickly went back up.

Handbook quotes "If oil climbs above 110 keep the revs below 5000 until the oil temp returns to normal"

Edited by FEE 50 on Tuesday 26th May 21:06

[nelly1]

You can get the sensor here...

Don't forget there are two sensors...



...the one for the gauge is on the right of the picture just underneath the second butterfly.

As for oil temperatures, in our dyno cells we run at 110°C on Performance tests and 125°C on Durability tests (on these tests the oil is changed every 100 hours).

This is on boggo 5w30 oil, and this is good for approx. 145°C before it starts to lose it's protective qualities.

Don't worry about an occasional 100°, it just looks worrying because the normal range is 70-80.

Edited by nelly1 on Tuesday 26th May 21:10

[shep1001]

Zippee said:

Whilst out on a run on Saturday my water temp went from running fine (90-95 on the move & 97ish in traffic) to all of a sudden hitting 115, 110, 95 back to 110 etc and the above error code.
I'm assuming this means the temp sensor has all of a sudden gone up the spout, if so where can I get one from? Is there any specific part number & how easy are they to fit? If easy can anyone give me a quick idiots guide to doing so ?

Also my oil temp at idle was hitting high nineties - what sort of temp is danger for oil? It did come back down on the move to 70 odd, but at idle once again quickly went back up.

Coolant temp sensor is in the block under the air box. About £16 for the part + £40 to replace. Not sure how easy it is to do mind. Had mine at Castle the other week, they found that mine had unplugged itself so no big bill there but my rad was knackered when pressure tested so cost me £650 for a new one!

[Zippee]

Thanks guys - Is the airbox easy to take off in order to access the sender?

At least it doesn't sound too worrying with either the water or the oil. Ah the joys and worries of first time S6 ownership!

[shep1001]

Zippee said:

Thanks guys - Is the airbox easy to take off in order to access the sender?

At least it doesn't sound too worrying with either the water or the oil. Ah the joys and worries of first time S6 ownership!

Don't think so but never done it myself I let Castle do it(have seen a thread on PH). Just be careful not to create an air lock when changing the sensor

[blackiepaul]

real easy to take the airbox off. Don't forget abvout the clip underneath.

[Zippee]

shep1001 said:

Just be careful not to create an air lock when changing the sensor

Air lock - check!! Erm, how do I ensure this??

[daveb500]

Zippee - my brother is just experiencing a similar problem with his Tuscan but it seems to be water temperature AND oil temperature that are erratic. The water is worse than the oil and seems to become more erratic the hotter the engine gets. Just wondered if you had managed to track down your problem.

I guess air is possible - he has just had a hose replaced - but would air make it that erratic? And why would the oil do the same? May be an earth problem?

Interesting addition to this - if you switch the engine off then turn the ignition on (but don't start it) the temperatures are steady. So they are only erratic while the engine is running.

Edited by daveb500 on Friday 5th June 08:41

Edited by daveb500 on Friday 5th June 08:41

[sidpinup]

I had high water temps being reported and the same error just this week. I had checked the water levels and all seemed fine so I figured it was the sensor. But it wasn't! I went for a drive of 5 milles and when I slowed the temp shot up and it even spat some water out of the cap. So got it home (temp was fine on the move) and let it cool and tested the water levels again and it was low so I topped it up but it didnt seem to need much. That didn't seem right so then I ran the engine with the cap off for a few seconds and it needed more coolant, same again and it needed another top up. In the end it needed 2 ltrs of coolant! Seems fine now and the fans do bring the temp down to about 88 in traffic. So it would seem that running the engine with the cap off when you top up gives a better level reading as I guess it may purge some air from the rad.

Edited by sidpinup on Friday 5th June 10:41

[Zippee]

daveb500 said:

Zippee - my brother is just experiencing a similar problem with his Tuscan but it seems to be water temperature AND oil temperature that are erratic. The water is worse than the oil and seems to become more erratic the hotter the engine gets. Just wondered if you had managed to track down your problem.

I guess air is possible - he has just had a hose replaced - but would air make it that erratic? And why would the oil do the same? May be an earth problem?

Interesting addition to this - if you switch the engine off then turn the ignition on (but don't start it) the temperatures are steady. So they are only erratic while the engine is running.

Edited by daveb500 on Friday 5th June 08:41

Edited by daveb500 on Friday 5th June 08:41

The water temp is eratic anyway as it is read every second (same goes for oil), therefore you should see fluctuations of 2-3deg. Mine though goes from 92-99-114-95 etc which is not right. The coolant was flushed and bled by my indie a month ago.
I'll be fitting the water temp sensor tomorrow so hopefully there'll be a difference.

[daveb500]

It sounds like exactly the same problem to me. At lower temperatures, the variance was smaller but when it gets around the 90's it seems to go a bit wild.

As I said though, the interesting thing was that once the engine was off, the variance stopped. I can only assume this is because there is no movement in the water.

Let us know if the sensor fixes it - I hope so, otherwise its time

[5yearstobuyatvr]

I had the same symptoms but mine was the fan switch sensor, the left hand one.

Edited by 5yearstobuyatvr on Friday 5th June 20:56

[HisNibsToo]

I had a similar problem after driving for a while the oil and water temps flutuate wildly on the screen but if you switch off and then back on they settle to normal then go haywire again.

It turned out to be a loose electrical connection causing disruption to the dash board lcd driver. It was temperature related due to expansion at the loose connection on the bulkhead. My understanding is that this can also happen with a loose connection on the Battery.

This may be the problem, hope this helps.

[Zippee]

Where is this connection? I switched the temp sender yesterday and it's not made much difference to the fluctuations (though has stopped the temp sensor error) - bugger of a job as well due to the tight fit behind other hoses!

[daveb500]

We've just fixed by brothers problem which sounded very similar to yours. It was an earth strap which connects from the engine to the chassis. It is located behind the drivers side front wheel. It connects to the engine mount bolt and was loose. Cleaned and tightened it and the problem has gone away.

[paul1962]

My Sag started doing the same thing on the way to work this morning.
Water and oil readings all over the place when engine running but OK when stopped.
Anything else to check other than the earth strap mentioned above ?
Also does this only affect the dash display, are the ecu readings still ok ? I *think* the fans were cutting in/out as normal.
It's being serviced in a few days so is it safe to use it like this until then ? Don't want to risk it overheating.

Edited by paul1962 on Wednesday 5th August 13:36

[Zippee]

paul1962 said:

My Sag started doing the same thing on the way to work this morning.
Water and oil readings all over the place when engine running but OK when stopped.
Anything else to check other than the earth strap mentioned above ?
Also does this only affect the dash display, are the ecu readings still ok ? I *think* the fans were cutting in/out as normal.
It's being serviced in a few days so is it safe to use it like this until then ? Don't want to risk it overheating.

Edited by paul1962 on Wednesday 5th August 13:36

I had mine looked at last month when I had a new alternator fitted. With a dash reading (water) of 92 to 110 and constant wild fluctuations the actual temps when connected to a laptop were 88 - 92 and very steady, cutting the fans in when required. Another new sender stopped the worst of the massive movements along with an extra earth strap. However, whilst my pod temps are now reasonably steady they do read about 6 deg over actual.

[VARLEYHYD]

paul1962 said:

My Sag started doing the same thing on the way to work this morning.
Water and oil readings all over the place when engine running but OK when stopped.
Anything else to check other than the earth strap mentioned above ?
Also does this only affect the dash display, are the ecu readings still ok ? I *think* the fans were cutting in/out as normal.
It's being serviced in a few days so is it safe to use it like this until then ? Don't want to risk it overheating.

Possible frayed wire on the sendor wire, can cause this?
Should be OK, check the ecu temp is not fluctuating to be sure.

G

[HisNibsToo]

I had the same problem 2 weeks ago when the alarm was playing up.
For some reason at the same time when driving the dash readings played up.
The alarm is sorted now and no more flutuations.
Were the 2 linked I will probably never know.
God Bless TVR electrics!!!