So, I have been driving my recently acquired car regularly, getting used to its quircks, squeaks, the lot. The inside is indeed slightly on the plasticky side, which is okay, but probably wouldn't have won over the luxery crowd back then. Inside it sounds a lot like the smart roadster I used to own, where all the plastic parts occasionally squeak under stress. In that sense I felt right at home and consider it "character". The car fits me like a glove, me being of standard height, but longer individuals should definitely do a testdrive. One should also not be claustrophobic. Everything seemed to operate as expected. No strange behavior, even under stress. I went out to buy some stuff, brought it back home. Parked the car up front, went inside the house, then back in the car.

Crank, but no start...

Crank, but no start...

(Notice that this conveniently happened at home with the car parked in front. Pffieh!)

Well, I already read on the forum that a start problem is mostly associated with the RCM, or less frequently the CPS. I didn't know the difference just yet, so I went to the forums and searched. Within minutes it was definite:

No crank is more likely the "Mystery no start"/RCM issue

Crank, but no start, is definitely not the RCM.

CPS problems are usually (but not always) associated with heat, if the engine cools down you can sometimes start. I tried later, and indeed it started right up, but also the Engine light was lit.

So the car apparently was saying to me: show me you can handle a CPS change in order for you to deserve me. It's the least you should be able to tackle, if you want to drive a car with character.

Oh well...

For the record: one additional (excuse the pun) "tell-tail" sign I noticed was when entering the highway on the ride home, the spoiler wouldn't go up at its usual speed.

Also for the record: I should probably read out the OBD before jumping to conclusions, but my reader was still on order, and replacing a CPS seemed to be a necessary skill as well as a necessary spare. Wouldn't hurt to practice that operation in front of the house, instead of on the emergencylane of a busy highway in the middle of commutertraffic.

So, i ordered the part and figured I should be able to tackle this in one afternoon.

It took me the entire $%#$@mn week.

Excuse me? Yep, you heard that right. Well, actually it took me only 5 minutes to install the new one, but it took the rest of the week to get the old one out. Here's why. I kept trying to attach the wrench to the bold. Somehow it never seemed to grasp. I was like ??? Tried several different torx and hexsizes. Figured at some point that maybe someone replaced the bold with something smaller or larger. Just couldn't figure it out. In my head the scene from Doc Hollywood played: Marvin finally has an excuse to order metric tools. But I am in Europe, I only have metric tools.

Would them Chrysler dudes perhaps bold the sensors with US stuff? That can't be right. I had more faith in the good forumpeople and if they say it's E8 torx, then E8 torx it is. One more try...

Clunk...!

Uh ooh. That sounded like a bold dropping.

It was. Conveniently again it lay nicely on the ridge right below the sensor. Someone with small hands could simply grab it. A magnet does the trick for larger hands. The heatshield would probably stop the bold from dropping anywhere unreachable, even though I read that happened to someone here.

But now comes the interesting bit(s). Because I never needed an actual wrench to unbold the bold, I must come to the conclusion that someone failed to tighten the bold properly. I can tell from the partnumber that it is already a replacement. No doubt if I read the documented history I will come across this.

The partnumber by the way, ends with 171 instead of the 170 I had just purchased. I presume it is the same sensor but renumbered to match the newer MBs, otherwise working as expected. As a sidenote I also came across an Hitachi 2117004846 which may be the OEM version of a MB v12 variant. It made me wonder what its operating temperature is. The 150deg celcius max stated for the Bosch sounds suspect to me, given its proximity so close to the exhaust.

Anyway, there was another issue that I would like to ask the forum. The old sensor seemed to have some dirt collected at the top, looks a lot like sticky sandgrains. The enginebay is definitely clean. It even has no indications of leaks like I saw on some other pics here. It's not powerwashed by the selling party, because I do have a dry leave or two that seem from way back. Nothing local, nor extraordinary.

So were does the sand come from? And should I worry that it may be on the flywheelteeth and between the startermotor gearwheel? The sensor's blank metal side was visible and looked fine. No sand there. The new sensor sits tight and snuggly. Can only install with lubricant.

Anyways, to make a long story slightly longer: after replacing the sensor, car runs fine. Engine light off. The OBD reader is in, but I can probably guess the codes if they were stored.