Technical Temp Sensor on Cinq

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Technical Temp Sensor on Cinq

nomatter

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One more question:

I guess cinqs have 2 temp sesors: one for the gauge and the other for supplying the engine with proper mixture.
Well, what exactly does this sensor do and what can be affected by it being defective?
Does it simply provide the engine with richer fuel mixture when cold and stops doing anything as the engine becomes hot? If so, what is the temperature of the engine where the sensor stops intervening?
Also, is it responsible for high revs when starting from cold?

Probably one sensor is located just above the thermostat; where's the second one and which is which?

Thanks again.
 
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The second is in the inlet manifold, cant remember which is used by ECU though. I believe its the one in the inlet manifold, but by no means certain.
 
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nomatter

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Can you explain what exactly does the sensor used by the ECU for engine operations do and what can be affected by it being defective?

Does it simply provide the engine with richer fuel mixture when cold and stops doing anything as the engine becomes hot?
If so, what is the temperature of the engine where the sensor stops intervening?
Also, is it responsible for high revs when starting from cold?

What is the ambient air temp sensor for and how does it affect anything?

I know you guys are genii :)
 

northernmonkey

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The temp sensor in the inlet manifold went on mine and it caused the car to run so rich you could actually watch the fuel needle dropping as you went along, averaged less than 20MPG. It adjusts the mix for how cold the air entering the engine is as you suspected the sensor for the guage is actually mounted on the block, cant really remember where tho.
 

Oldschool

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northernmonkey said:
The temp sensor in the inlet manifold went on mine and it caused the car to run so rich you could actually watch the fuel needle dropping as you went along, averaged less than 20MPG. It adjusts the mix for how cold the air entering the engine is as you suspected the sensor for the guage is actually mounted on the block, cant really remember where tho.

The airtemp sensor is in the throttle body housing. The sensor on the manifold is for the cold starting. It measures the water temp in the inlet manifold water jacket. During warming up it is overfueling the engine because of fuel condensation when the engine is cold (fubctions like the choke in carbs).
 
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nomatter

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Is the item numbered 1 the temp sensor used by the ECU?
022.jpg


When I disconnect the connector nothing changes; engine revs remain high if the engine is cold and revs are low if the engine is hot. The Voltmeter reading from the sensor is 15mv.

What is the connector 2 for? It was disconnected when i first saw it. Any use of it?

Thanks.
 

arseofbox

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Nope, thats the gauge sender.

As Oldschool said, the Air Temp Sensor (ATS) is in the throttle body housing
 

arc

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it looks like a gauge sender as tom has said

assuming u have an 899'er. the coolant temperature sensor for the ECU is in the top of the thermostat housing.
 
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nomatter

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OK, it is the gauge sender (I have 899'er).

Above Luke1985 said that the ECU temp sensor is in the Inlet manifold and rallycinq agreed.

The inlet manifold is the pipe isn't it?
So where is the engine temp sensor for the ECU (same as the coolant temp sensor, right)? On the Thermostat (and i believe it comes with a new thermostat) or in the inlet manifold?

How can I access the sensor in the inlet manifold?

And, how many temp sensors are there? :bang:
 

arc

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there are two coolant temperature sensors and one air temperature sensor.

on the 1108cc engine the ECU coolant temp sensor is in the inlet manifold, on the 899cc engine the ECU coolant temp sensor is on the thermostat like i said up there! :)
 
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nomatter

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Aaah, I see. Thanks for enlightening me.

So as i replaced the thermostat recently the ECU temp sensor is also new; (correct me if i'm wrong).

OK, now i'm going further trying to figure out what is causing overfueling. So the following items are fine:

1) Temp sensor (on the thermostat)
2) no dragging
3) new filters (oil/air)
4) cat's been removed so it can't be causing any problems.
5) diagnostics reported no errors in the ECU (i get no ECU warning lights either)

Starting/acceleration/driving is smooth/without problems.

What else to check?
 

arc

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i've never worked on an 899 before so i don't know if you'd get a new ECU temp sensor with a thermostat.. on the 1108 the ECU temp sensor costs around £30 and considering both cars use the same managment system i imagine the sensor is the same, and therefore not likely to be a part sold with the thermostat (unless the thermostat is very expensive!)

Has your car had a new fuel tank fitted under recall ?
 
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nomatter

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I'm not sure what was changed in the car before i became its owner. For as long as i have had it no fuel tank has been replaced. I think no one ever touched it as many parts in the car are intact.
By fuel tank you mean that the rubbish accumulated at the bottom could be jamming up something?

I'll double-check the temp sensor on the thermostat to make sure it's fine.
 

arseofbox

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arc said:
i've never worked on an 899 before so i don't know if you'd get a new ECU temp sensor with a thermostat..

You dont. Its a £35 swindle for a 'stat on the 899cc...

arc said:
considering both cars use the same managment system i imagine the sensor is the same, and therefore not likely to be a part sold with the thermostat (unless the thermostat is very expensive!)

Its electronically identically, and IIRC its the same spanner size..I'll try and rip mine off my 899ccer and compare it to the 1242 one...
 

arc

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nomatter said:
By fuel tank you mean that the rubbish accumulated at the bottom could be jamming up something?

nah, they were all recalled because of dodgy weld on a seam. it could be leaking
 
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