Difference between IAT sesnor and Coolant temperature sensor?

[Gabriel2202]

I know this sounds really dumb, but im new engine work and have been told that changing my coolant air temperature senor may be the cure to low mpg.... I have been looking for parts online and euro car parts only do an intake air temperature sensor (which looks the same and is green 4-pin push in like the coolant air temperature sensor is). I thought the IAT sensor was threaded near the throttle body? whereas the CAT sensor was the green 4-pin push in to the right of the engine? 

Am i right in thinking this? Could someone set me straight on this please on the differences?

[javalin]

I think you mean changing the "coolant temperature sensor" or "CTS" which has a large amount to do with fueling.

The "Intake Air Temperature" Sensor (or IAT) which measures intake air temp has very little impact on the fueling.

What car?  On the mk3 its a push in with a clip.

James

[Gabriel2202]

I think you mean changing the "coolant temperature sensor" or "CTS" which has a large amount to do with fueling.

The "Intake Air Temperature" Sensor (or IAT) which measures intake air temp has very little impact on the fueling.

What car?  On the mk3 its a push in with a clip.

James

Ah yeah, cheers, that'll be what i mean  :embarassed:.... sorry should have put its a mk4 golf 1.8t... I have changed the lambda sensors and the MAF which made a difference but its still very low! So going to try changing the CTS but both the IAT and CTS i have seen photos of on euro car parts and the bay look exactly the same though??

[javalin]

goto VW, http://www.vwspares.co.uk/g4cooling.php or GSF - don't bother with ECP

Just change the CTS for the time being too - IAT won't be causing it.

James

[Gabriel2202]

goto VW, http://www.vwspares.co.uk/g4cooling.php or GSF - don't bother with ECP

Just change the CTS for the time being too - IAT won't be causing it.

James

Great, thanks for all your help mate