IAT

[metalworker0]

Well they work on resistance don't they, so anywhere in the circuit that has high resistance would make the software show very low temperature ..that would be fuses, wiring or a relay , corrosion where it screws in, if its a one wire type ..or even you using ptfe tape, or sealant on it .

All the best..mark

[metalworker0]

I found this site that has a lot of information on testing the sensors

The site even the resistance values at different temperatures ...which may help you prove that your new one is also faulty

https://axleaddict.com/auto-repair/Inta ... ensor-Test


All the best.mark

[walt1984]

Thanks for info.
Mines part of the mass air flow.
It was changed for a hella version, I bought a cheap one to try and butcher up, then spent £100 on a decent one.
They all read the same.
Wirings fine with no breaks and multi plugs are clean.
If I shorted it out it reads -50c and a open circuit was something like +37c.
It's like it needs to re learn that 10c is 10c If that makes sense but I havnt a clue how to go about it.

Sent from my SM-A107F using Tapatalk

[walt1984]

Just incase anyone has the same problem I've finally got to the bottom of it.
Been ignoring it and putting up with it for last few years but recently bought a low mileage 2014 custom that unfortunately had developed a starting problem.
Pratting about swapping things between custom and mk7 iv3 found out that there is a euro 4 and 5 mass air sensor.
My mk7 is a early euro5 with an identical engine, air box etc to the custom, when I put my reg in online it says the custom maf is not correct for the mk7.
Put a new custom maf in and the mk7 now starts as it should with out cycling the key and starts when warm without a fast idle or switching its heated screen on in the middle of summer.

[Altransit]

Thanks for the update Walt