Using a heat gun to remove a stuck abs sensor

As title says, I replaced the front sensor and I quite honestly say it was one of the worst jobs I have ever done, had to drill it out but the material used internally is just so dense and the drills hardly make a dent, had to go round the outside of the plastic carefully but it took hours to remove. I know need to do the rear one. Has anyone tried using a heat gun to try and help remove the sensor, will I damage anything locally by using a heat gun?

Not removed ABS sensors on a Porsche, but have done on Audi TTs in the past. You are 100% right - when a European car is 10+ years old, not an easy process. In the past, have used drills, heat guns, blow torches, drifts with a lump hammer, lots of penetrating fluid, etc, or a combination of them all. A nightmare job for something that should be relatively simple. On Audis, the housings gave been steel/iron so not a problem with taking a bit of localised heat. Have heated the sensor up and then doused with water to achieve rapid contraction. This has broken the bond. Caution!!! If your housing is aluminium and/or there are electrics/piping/seals nearby, be careful with heat as it may permanently soften the aluminium structure or cause melting/damage. Good luck, and let us know how you get on.

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Ugh, sounds like a nightmare with that front sensor! A heat gun could help soften the plastic and make it easier to remove, but you’ve got to be careful. Too much heat could mess with nearby components or wiring. Try using it on a low setting, and keep the heat moving to avoid overheating any specific area. Should make the job a bit smoother

The time spent drilling it out could have been spent taking the drive shaft out ,after undoing it from the front diff if yours is 4 wheel drive and using a drift push it back up and out of the hole. Both screws were drilled out and retapped, as I was doing a complete suspension rebuild it was an easy job. I then used copper slip when I installed them. Each year I will remove them and apply some until I know a period of time when I can increase the time span.

All I can say is when I did my wheel bearings I thought I'd "pop" them out to get them out the way but both cap head bolts snapped and it would not come out so I left it alone , it doesn't need the bolts anymore. Impossible to press out too. Sounds like a terrible job with very little reward.

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That's a Top Tip - did exactly that with mine on the Audis.

You've also got the wheel bearing dust shields in the hub made of plastic but I doubt you'd get enough heat in the hub to damage them (or boil the grease).

Just done the rears on the mine as a "while you're in there" with the hubs removed. You have to be resigned to the fact that you're not going to re use them. They just don't come out easy as mentioned. I found the quickest way to remove them was to break the head off and then with a small drill bit, drill several holes between the central magnet and the outer plastic casing. You can then drive the guts of it out and the break the plastic case. Definitely needs some kind of anti seize on the replacement.

By the way, you want Alu Slip and not Copper Slip on these wheel carriers, copper can create galvanic corrosion and fuse them together as badly as the bare materials. Same with the pinch bolts holding the strut/drop links in.

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Thanks for the heads up, still surprises me how plastic can weld onto metal as if it was super glued in place

Yeah, same here, I guess it is simply years of heat cycles? I suppose it just melts into the carrier in the end? Why are you changing them by the way? They very rarely fail, and you have two gone? You sure it is not the harness leading to the sensor? That cable is the one that flexes constantly and fail at a fair old rate. Porsche sell a repair harness for this now, around 2ft long. I actually have a spare one sat next to me for some reason, no idea why it is in the spare room and not in my garage, but it is. But have you tested the sensor itself? Just in case anyone reads this in the future and doesn't know how to test an abs sensor, you just need a cheap multimeter, Unplug the sensor on the carrier, stick the red and black on the sensor pins, set it to Ω and it should give an ohms reading, if it is 0 it is gone. Takes 30 seconds.

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I’ve bought a Bosch sensor ready to fit, but didnt realise it could just be the wire, so will definitely check that before fitting. My car has done 200k so maybe not that unusual. If the sensor is ok and it’s the wire, are you looking to sell your repair kit?

Sensor Checked with meter, sensor was reading 0 ohms, so was definitely faulty and not the harness. Swapped out the old sensor,Took a couple of hours again, I can confirm the heat gun made no difference, it just made it snap quicker, so had to drill out as before. Reset fault codes and it’s now running perfectly. Once again, thanks for everyone's help.

Cool. 2 hours is not too bad in the grand scheme of things!

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Uncle Monty, Are you still running the car with the snapped cap head bolts off ? My rear offside cap head has snapped off. I've tried with light force to prize out the black plastic sensor but she will not budge. So after reading the threads on here, i'm thinking of leaving it in. My C2 3.6 has been in the garage since end of Sept as i'm cleaning underneath. After each day of cleaning and then steam cleaning off around the hub / suspension and the underneath of engine i always start the car to get some heat to dry it off. A few days ago i started the engine only to have the ABS / PSM lights on. That's why i wanted to remove the sensor. It's only on the rear offside hub / suspension that i was working on. Ultimately i'd want to change the cap bolt which i now have from Design911, even if i just drill out the thread, re tap etc Be interested to have thoughts on whether to leave it as it is and carry out fault finding on the wires