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Gold 'N' Brown
Sunday 11th September 2016, 16:50
Early PH2 V70 T5. Just found that my loom has snapped right where it goes in to the plug, for what I'm guessing is the intake temp sensor. It's the one right next to the BPS (MAP sensor?) in the intake pipe that goes between the intercooler and TB. The BPS has 3 wires and is fine, the other one has two wires (the ones that have snapped).

Q1 - Is it the inlet temp sensor?
Q2 - Would this cause the ECU limit boost?
Q3 - Anybody know what sort of terminals these loom connectors use? Are they Volvo specific or can they be bought elsewhere? I have a crimp tool and terminal extraction kit and I've some experience building looms. Would rather crimp on new terminals than try to resolder the connections if I can get replacements.

EDIT: Having thought about it I realise it's not the IAT as it's post intercooler (IAT would be right at the start of the intake, possibly part of the MAF, yes?), but I'm presuming it's still some sort of charge air temp sensor.
EDIT 2: OK, looks like it is the IAT, which is separate to the MAP on <2003 models.

Gold 'N' Brown
Sunday 23rd October 2016, 12:57
Managed to get lucky as a local breakers had a V70 2.4 turbo that still had the sensor and loom in tact, so I managed to get the connector with 12" of tail, and grabbed some other odds and sods off the car while I was there all for the princely sum of £5.

Cut back my loom, soldered the donor wiring and connector in place, wrapped with self amalgamating tape and some new convoluted loom tubing and all is well again. Boost restored.

Quite an interesting learning experience, seeing the effects of a non functioning IAT sensor. Performance was down, but I wouldn't say massively. For most "normal" driving it behaved well enough. Low RPM performance and pulling up hills was a real giveaway. There's one really steep hill on a residential street which I found if I was going up in 2nd at ~15mph the car was really bogging down. Now it will happily accelerate on part throttle from the same speed on the same hill as you would expect. And although it seemed "OK" for general driving as I said above, having the performance restored post-fix I can really feel the improvement and it feels so much more responsive from low revs.

I presume this fault would have thrown a code. I don't have a code reader and still haven't got around to getting VIDA working. But I did buy the Torque app and an ELM OBD connector just prior to finding this fault, and I actually commented on here that I found it odd that Torque was showing my IAT reading as a constant -40 degrees. It was spelling it out to me but I just assumed it was the app not being great!

So it's another thing worth checking if you ever have any low boost/performance issues.

LeeT5
Monday 24th October 2016, 20:02
There will definitely be a fault code or two.