mikrt

Bought my A4 (B7) 2008 privately yesterday morning, and didn't notice till last night that the ECON is on all the time. After a quick google it seems likely cause/s can be faulty A/C thrust pressure sensor and/or low level gas (either lost over time or due to leak).

Don't want to buy sensor (and remove bumper etc) if not needed, so I intend just regassing first to see if that fixes it.

My question is, can the sensor be removed with system under pressure? Or will I lose all the fresh gas (and cash)?

Intuition tells me it's not a good idea, but there are write ups online that say it can be done.

Thanks in advance

Dwes

Doing the same thing to mine, gotta take the bumper off to get to it, and you won't need to evacuate the system.

Access is super limited because of the front grille, bumper, fan shroud, and radiator which all surround it. From what I've read it's just screwed in there with a schrader valve (think like the HP or LP port) so you won't loose any refrigerant when you remove it.

Getting the bumper off isn't too bad. Worse part of it is access to the 10mm bolts that attach it to the quarter panels, through the wheel wells. If you need a DIY or instructions on that I can give you some guidance.

My "thrust" valve shows up tomorrow and I'll be installing this Friday I'll take pix and post up a DIY if it'd help.

-Dave

mikrt

Thanks Dwes,

Car should have A/C system pressure tested today, so if it's low I can refill there & then, and if OK, I now know I can safely remove the thrust sensor.

Shrader valve! I should have worked that out, but couldn't figure out the size of it from pictures online.

Pic's would be great.

Thanks again.

Dwes

So got the A/C all fixed up and working this weekend, it's great to have cold air flowing again. In my early morning shenanigans I didn't get a chance to take pictures. However there's a great diy that I used on the ECS site for a timing belt replacement.

http://bd8ba3c866c8cbc330ab-7b26c6f3...llation_r3.pdf

Since my A4 had fog lights without the grille you can skip the fog light removal step. They just come out with the bumper. Since you only need to get to the front of the condenser you won't need to remove any of the lock carrier bolts/torx screws. The thrust sensor is attached to the drivers side of the condenser. You may be able to reach around the big aluminum "impact bar" but I took mine off. You'll need an M10 triple square to remove the bolts.


Bumper and impact bar removed. Thrust sensor location.

Hope this helps, good luck!

-Dave