Not fixing the temp gauge

[Pakman]

Hi,

My friend and I are having a debate and need some clarification if someone has the correct answer please?

My temp gauge in my car despite a new thermostat, and ECT temp sender sensor being replaced is still behaving like Harry potter is playing tricks on me!

So our debate is, what does the temp gauge actually control because my friends argument is that if the car had an overheat problem or ran low on coolant, then the temp sender and the coolant prongs with the engine management system, would send a red warning light to the dash so in essence you don't really need the temp gauge in the **** pit? I am trying to avoid costly diagnosis and repairs at the moment because I am skint and if it isn't necessary I would rather leave it for now. I have plugged it into a cheapie scanner and no faults are coming up anymore since fixing the stat and ECT (previously these were highlighted by it)

Your help would be greatly appreciated to settle our debate thanks

 

[addavis89]

Tells the ecu the temperature so it can work out fuel to air mixture needed.

 

[Pakman]

I thought that was what the temp sender (ECT) does? I was under the impression the cockpit dial was for the drivers benefit?

 

[Muttley]

The temperature sender (CTS) contains two separate sensors (that's why it's got four electrical connections). One sensor (G2) feeds the dash gauge only; well to be strictly accurate, the dash control unit. This is the one that gives you an estimate of the engine temperature, and also activates the red light in the coolant gauge if it detects overtemperature.

The second sensor, G62, is wired directly to the ECU and is used to calculate fuelling.

Have you tried cleaning the contacts in the connector and the sensor itself?

 

[deburgh999]

whats your gauge doing?

 

[Pakman]

The temperature sender (CTS) contains two separate sensors (that's why it's got four electrical connections). One sensor (G2) feeds the dash gauge only; well to be strictly accurate, the dash control unit. This is the one that gives you an estimate of the engine temperature, and also activates the red light in the coolant gauge if it detects overtemperature.

The second sensor, G62, is wired directly to the ECU and is used to calculate fuelling.

Have you tried cleaning the contacts in the connector and the sensor itself?

Hi muttley, that makes sense as I have changed the parts, I have not cleaned the connections. What's the best route for this you reckon? Is it a case of some wire wool on it? The sender was fitted in August so I don't think that needs cleaning but the wiring is old so i would be interested in some help with cleaning that.... Might save me some cash

 

[Pakman]

whats your gauge doing?

Hey, I wrote this down this morning as a reminder of what it does

Finally drove car for a longer period:

Car got up to temp in 4 miles at 0 degrees outside temp. Once to temp kept sharply dropping down. Was going to go for a longer drive but started smelling coolant through the heaters even though the gauge was only on the 1/4 mark. (Bolder mark before 90)

Thermostat through you.
Temp sender in August

 

[CupraRmark]

Have you used a eBay special cts coolant temp sender, if so known a few of these to fail and be probmatic

 

[LEE69]

Hi muttley, that makes sense as I have changed the parts, I have not cleaned the connections. What's the best route for this you reckon? Is it a case of some wire wool on it? The sender was fitted in August so I don't think that needs cleaning but the wiring is old so i would be interested in some help with cleaning that.... Might save me some cash

Scrape them with a screwdriver.

 

[Pakman]

Have you used a eBay special cts coolant temp sender, if so known a few of these to fail and be probmatic

I did buy from EBay but my scanner says its working fine so I don't think I got a dud one and they seemed quite a reputable ebayer. I didn't just pick the cheapest seller I read what they had to say about them because I got caught out like that before with a non Bosch MAF and all I achieved was wasting my time - I had heard they can be problematic. Had it thrown up a fault I would have agreed with you.

 

[LEE69]

There is only two things in the system a thermostat and a cts.
So one of them is faulty.

 

[Pakman]

Scrape them with a screwdriver.

Cheers Lee, because I don't fancy whipping the sender out now I've just put new coolant in it! So scrape both the connection on the sender and the connection on the plugs (I can't visualise it; I didn't pay much attention when I fitted it in all honesty)

 

[Pakman]

There is only two things in the system a thermostat and a cts.
So one of them is faulty.

Yeah well both replaced so must be the connections

 

[LEE69]

No, open the bottle cap and scrape the ones inside

 

[LEE69]

Yeah well both replaced so must be the connections

Or one is faulty

 

[Pakman]

No, open the bottle cap and scrape the ones inside

I was told that just does the levels

 

[Pakman]

Or one is faulty

I hope not they're both new and I'm hoping the scanner would pick up on that

 

[LEE69]

It also stops the light in the fuel gauge from beeping and flashing at ignition on

 

[LEE69]

I hope not they're both new and I'm hoping the scanner would pick up on that

I have known a stat to fail on fitment, and a cts

 

[Pakman]

I have known a stat to fail on fitment, and a cts

Well, lets hope not. I'll do some cleaning of the rods in the coolant reservoir and the connections on the CTS and see how I fair