Crank sensor problem (noticed something else)

[Vinnienova]

I hope someone can guide me in the right direction with this. I have a 1.0 mpi 2001 51 plate blue lupo that had an engine management light issue which turned out to be leads n plugs after and a stuck EGR valve. Fault codes p0404 p0302. Leads were replaced and EGR valve cleaned and all codes cleared. I noticed a longer than usual turnover before the engine fired after these problems were fixed and managed for a good week being able to fire the lupo up and get about ect, but as times gone if left over night struggles to start. I managed to bump start it only the other day after priming the pedal ect and once running would start after a few hours fine but left overnight was faced with the same issue of a non starter just turns over but doesn’t fire almost does on occasions. So I diagnosed and brought back a pending code p0321 which I believe to be the crank sensor or speed sensor? I’ve located it but I don’t know how to fully reach the part I’ve got as far as taking off the filter housing (removed battery) I have the new part crank sensor and hoping that I can fit this myself with some help and knowledge of how to remove the old one. I’ve found the connection for it but the crank end seems to disappear into the crank body? What is my next step moving forward. I’ve attached a photo of something else I’m not too familiar with it’s a white plastic cap that appears to be open below the coil should this be open? Also the bottom picture is I believe the location of said crank sensor. (Not my engine) 

[mk2]

Not sure if it's the crank sensor. The symptoms sounds very much like the coolant temp sensor, which is really common on our Lupos (and so many other Vdubs of that era). @Rich what do you think?

Can you use your diagnostics to see live sensor data? Worth checking if the temp readings look correct...

And welcome to club Lupo

Pic of car?

 

[Rich]

Crank sensor plays up when warm, coolant temp sensor plays up when cold.

Yours sounds more like disturbed vacuum lines on that awful auc engine around the egr. 

They're particular about that stuff.

[Vinnienova]

Thanks Rich but I don’t think it’s coolant temp sensor as I’ve not had many warnings no black smoke engine heating steady does get halfway on the temp needle gets very warm inside but it’s been like that since I’ve had it the past 3yrs! I’m still scratching my head on what the white cap is and why it’s open? I could try changing the coolant temp sensor first maybe it’s far easier than the crank sensor (still hoping to find someone in here to advise on fitting crank sensor) car if I somehow get it going miraculously will drive fine no issues apart from maybe getting warm quickly but temp stays steady at halfway. Really got me stumped 

[Vinnienova]

Thanks mk2 pic of car is 2001 1.0 mpi lupo been a good car for 3 years hoping to get this sorted over the weekend so any help is appreciated. Need to know where to go from here or what to start with don’t want to be creating a big job over a crank sensor that maybe works fine. I may have a voltmeter somewhere will keep you posted. Still trying to figure out what this white plug that’s open is for??

[mk2]

That's a marker bung in the gearbox bell housing so you can line up crank TDC. There's usually a line on the flywheel with a little "0" next to it.