x20xev crankshaft sensor problems

[ilovedmymantas]

Short version -
holiday booked for last week, leaving monday. Car failed to start sunday night when i was going fill up with petrol & air, three hours later aa guy turns up and cranks it beyond popping and the engine starts. It ran perfectly , went last minute shopping an hour later and decided to fuel up in the morning because it was getting late.
Monday morning, all loaded up and ready to go, no start again . While i was waiting for the aa, who bumped me down the list from 1hr to 4hr eta i did a paperclip test that surprisingly showed no stored fault codes. when they arrived and tried it wouldn't start, it was over fuelling so they thought temp sensor. They towed it to the garage i use - goodbye holiday.

A few days later.....

I was impressed he managed to borrow a tech 1!

This sensor was only replaced in winter.
As it stands, i'm tasked with finding one of these, a seemingly impossible one if my last three days searching are anything to go by.
- Opel part no. 1238914

VDO 5WK90541Z seems to be what i'm after but i can't find anyone with it in stock, my second and most expensive choice Hella also seems discontinued https://spareto.co.uk/oe/90458251
My options are down to NGK (don't know how he'll feel about that, he changed the ngk spark plugs and the car did run smoother) or Quinton Hazell (not sure about quality since tetrosyl bought them).

Tomorrow I'll try vauxhall again, their online catalogue was down on friday, and a local dingbro listed as VDO suppliers. I know they're trade only but if I can confirm they can get one maybe my garage will take the responsibility again.

Side note - there are many aftermarket ebay listings for this stating part numbers that don't match the 7zap epc which is GM 90458251.
I don't suppose anyone has one or the Opel equivalent 1238914?

[Robsey]

If it is a crank-shaft sensor, I would recommend a metal-bodied Bosch sensor.
The plastic ones can twist and distort.

Assuming it is a universal Vauxhall Cavalier item (also C18NZ / C20NE part as the online site appears to confirm).

Search for -
bosch 0261210030







Sometimes the sensor moves out of alignment causing the signal to be lost.
On the odd rare occasion, you can remove, refit and re-seat the sensor squarely to get the signal back.
But not very often.

I presume as the garage had a Tech 1 unit, they will have checked the connector at the back of the block / in the trunking.

[Robsey]

Just for info -
the crank angle sensor fault code is an odd one to catch.

The code will always flag up until the engine fires up.

As soon as the engine starts, it is the only code that is immediately deleted from the fault log memory.

The fault code will only remain stored in the log if the signal is intermittent.

[ilovedmymantas]

I tried the bosch number but it seems to fit almost everything except the xev which is frustrating. I've confirmed this using autovaux and another reg no. part checker.
I didn't manage the phone calls, it was an off day, It will probably be wednesday now. Time to shut down the seventeen open tabs and start afresh i think

[ilovedmymantas]

Update.

i've given up on finding an original siemens/vdo sensor. I called vauxhall, none, called vdo, none.
Called the garage, both sensors used were cambiare ( i couldn't find anything negative said about them) and were the correct part number.

I paperclipped the car earlier and two codes came up, 19 Incorrect RPM signal (Crankshaft sensor - incorrect signal) and 93 Hall sensor - voltage low (Quad Driver Module). Tech 1 only showed 19.

I tried starting but no joy. It did try but it felt violent so i stopped. Central locking also locked the doors so I'll charge the battery tomorrow, i'm assuming that was the cause. I wonder if that's why the 93 code came up?

Unless i've been unlucky and both sensors came from a bad batch (i have no way of checking) I have to think the problem is elsewhere.

But where?
Timing was checked and good, i can't see it being the reluctor ring but if that was suspect i do have a newer sump pan i wanted fitted so inspection would be possible (oil level sensor doesn't work on the current one that's a bit beaten up with speedbumps).

I need to get back on the road, any thoughts appreciated.

[cavalier1990]

Seen one listed at site below. Is the c20xe same one as x20xev, got to admit knowing practically nothing about these variants of engines, but it does say bosch 0261210030? All the other ones I've seen are out of stock or north of 100 bucks

https://www.andersonracingengines.com/b ... aft-sensor

[thomas]

Only myself figuring where these engines are found also, and identical Simtec 56.1: Astra-F and some but not all Omega-B, with 56.5 Omega B again and Vectra-B.

Have a fault-code book which offers this:

"RPM signal or RPM circuit interrrupted" is given for 19

93 is the 'Hall-Effect Sensor circuit low-voltage' on Bosch Motronic
There is a note on 93 "Quad drive module (in ECM)" with GM-Multec thus: "If code 93 (quad-driver) is present the fault may be in one of three circuits: a) Warning light circuit b) Air-conditioning circuit c) Engine Speed signal to Automatic Transmission ECM". It also says "If the quad-driver is actuated the FCR (reader) will test the circuit and report which is the faulty one".

Simtec isn't mentioned specifically for that code, but they all share some codes.
A 19 could lead to a 93. Is it an auto-box?
HT leakage, tracking or open-circuit somewhere possible.
Be worth seeing if there is not just 'a spark' but a spark on either of 1 and 4, and either of 2 and 3.

Good luck.

[Robsey]

There are three versions.

56.0 which is usually the Cavalier and early Calibra.

56.1 = later Calibra and early Vectra-B

56.5 = later Vectra-B and Omega-B.

If your ECU ever fails, ensure you get the same alfa-code.
The ECU is wired up completely differently for each version.

[ilovedmymantas]

Thanks for the quick replies.

Seen one listed at site below. Is the c20xe same one as x20xev, got to admit knowing practically nothing about these variants of engines, but it does say bosch 0261210030? All the other ones I've seen are out of stock or north of 100 bucks
https://www.andersonracingengines.com/b ... aft-sensor

That's a really good price. It don't think there's a bosch one that fits my engine but if I had a c20xe I'd snap that one up for future use.

Only myself figuring where these engines are found also, and identical Simtec 56.1: Astra-F and some but not all Omega-B, with 56.5 Omega B again and Vectra-B.

Have a fault-code book which offers this:

"RPM signal or RPM circuit interrrupted" is given for 19

93 is the 'Hall-Effect Sensor circuit low-voltage' on Bosch Motronic
There is a note on 93 "Quad drive module (in ECM)" with GM-Multec thus: "If code 93 (quad-driver) is present the fault may be in one of three circuits: a) Warning light circuit b) Air-conditioning circuit c) Engine Speed signal to Automatic Transmission ECM". It also says "If the quad-driver is actuated the FCR (reader) will test the circuit and report which is the faulty one".

Simtec isn't mentioned specifically for that code, but they all share some codes.
A 19 could lead to a 93. Is it an auto-box?
HT leakage, tracking or open-circuit somewhere possible.
Be worth seeing if there is not just 'a spark' but a spark on either of 1 and 4, and either of 2 and 3.

Good luck.

`
Thanks.
It's not an auto box but it does have defunct aircon .
I wonder if a coil pack problem would show up as code 41- 1 gear ident switch - voltage low C20LET OR EST Line Coil Cylinder 2 & 3 (Voltage High) M2.8 / XEV
or code 42 1 gear ident switch - voltage high C20LET OR EST Line Coil Cylinder 1 & 4 (Voltage High) M2.8 / XEV, Tech 1 only showed 19?

Just for info -
the crank angle sensor fault code is an odd one to catch.

The code will always flag up until the engine fires up.

As soon as the engine starts, it is the only code that is immediately deleted from the fault log memory.

The fault code will only remain stored in the log if the signal is intermittent.

Could intermittent/incorrect signal be caused by faulty loom wiring?

After many years with no issues this problem is walking me nuts ( well, It can't drive me nuts )

[Robsey]

Intermittent signal could be a range of things.

1 - damaged screen on the cable causing noise / interference on the cable.

2 - loose, damaged, dirty or wet connector plug.

3 - low overall system battery voltage

And finally - the one you don't want. Engine ECU on it's way out.
But check all loom feeds and earths first.

[thomas]

As you mentioned fuelling it, I'm sure someone has already suggested the D-word.
Not hearing from you assumed you'd put diesel in it then gone off on holiday to forget.

Think the 93 is just spurious due to the 19. If a genuine 93, you should should have got another code identifying high/low and which of the dual-coil pair.

Thought HT, as though the paired coil on-time can be longer, than a single coil, it has two arcs/sparks to start and maintain, and the one in the the cylinder at the end of the exhaust stroke, at near atmospheric pressure probably easier for spark to jump in than in the charged cylinder ready to fire.
That and if you lose 1 cylinder it'll probably still run on three, but lose two cylinders, two sparks (through DIS design) it'll not.

These are the chapters and sections of the manuals we skim past, with a sense of relief that we don't have to deal with any of that stuff.
That lead you out of blissful ignorance into the realm of these rarer models.
As you've got both crank and cam sensors.
Could try with just the crank sensor connected, cam sensor not and vice-versa.

It is claimed it should be able to run with either of them alone.

[Robsey]

There are actually three sensors on the XEV.

Crank Angle Sensor,
Camshaft Position Sensor
And
Knock sensor.
And all the connector plugs look the same.
It drove me crackers when I converted a Cavalier loom to fit the Vectra-B ECU.

[thomas]

Hi, Robsey.

All that redundancy, but one faulty spark-plug, or lead, rare though (to ground) could stop a pair of cylinders.
It would seem sensitive then to plug-gaps, variation in them, or weak sparks.

It's difficult to keep in mind that the pairs of plugs are in a loop with the head itself providing the link.
Something like: coil-plug-head-plug-otherendofsamecoilsecondary.

[thomas]

This is what my component tester makes of a hopefully good, new (VDO D30007, came in febi packaging) crank-sensor, pins 1 and 2.



530ohms resistance, and an inductance of 232 milliHenrys.

[ilovedmymantas]

Thanks guys but all this is over my head these days.
I'm still off the road and in the doldrums. I've tried every auto electrician through yell, Thomson local etc. in a 30 mile radius. One wrong number, one no longer in use, three answering machines with no call back and when I finally found someone he told me he retired after forty years and did the odd job but he wouldn't touch this

I'm relying on taxis to shop once a week for now, too scared to force it to start in limp mode in case it breaks the timing belt that's long overdue for a change. I have a gates kit and a new gm water pump ready for fitting but I need to fix this problem first i think. The X20XEV is an interference engine, I rebuilt the previous sri one after a belt snap, I couldn't do it now

I have to assume the crankshaft sensor is good and it's loom wiring? With that in mind I dug out my test meter. Why isn't anything straight-forward? One of the heat-sealed probes has a broken wire inside, need to fix that first
I can just about manage a continuity test, being colour blind doesn't help but it's three wires so fingers crossed.

[thomas]

Feel for you Matt. I'm sure many others Robsey for certain have this problem in their minds too and are trying to think this through.
I can think of a couple of people locally, for whom this stuff is their meat and drink who can out-think me, days, weeks before I've caught up.

I don't touch or have anything to do with ignition/injection stuff, left alone they usually just work, but sometimes have to be disturbed.
For a non-runner I wouldn't hesitate to hand it over to trusted people in the trade, with day-in-day out familiarity with and knowledge, who have the task-specific tools and equipment to diagnose and repair. The chances are high of damaging delicate static-sensitive mosfets and stuff, unseen damage that doesn't cause complete failure immediately.

There are things you can do, with the battery disconnected, removed, ideally taken indoors and put on charge.

It would really be best to try to rule the crank-sensor and its wiring out.
It has a resistance, it has inductance, it has frequency-dependent inductive reactance and impedance.
Between the core wires (1&2) and the earth screen (3) it has capacitance.

I don't have a wiring diagram for this model, but the wiring colours for some things seem consistent across models/engines.
Brown pin 3, earth. Check your earths on pin 3 of crank-sensor and pin 3 of cam-sensor feed wires.

Grey/Red pin 2, Grey/Black pin 1.
Check continuity on each one of these, all the way back to the ecu, whether motronic/multec/simtec to whatever pin number there accordingly.

Cam sensor ditto. Would expect (have no specific wiring-diagram) the signal pair to be brown/black (2), which goes straight to the ecu on c20xe, and brown/grey (1) which branches to lots of other areas (like fuel-pump relay) and might be red/blue at the ecu end.

If you can get the timing-belt cover off, check crank sprocket and cam sprockets' TDC/keying marks still line up, that slippage hasn't already occurred.
If these are bang-on, and it steers and stops, and the trip was essential I'd use it.

Much of this has probably already been done.
You don't need good luck, just take it one thing at a time, when we know what it isn't, it'll be the last thing left, it always is.

[thomas]

There are shortcut ways to do all the above. Which sometimes strike you as you're doing it, which you can then add to your toolbox.
So that it can be done mostly be done from the comfort of having your head in the driver's footwell.

That is to disconnect crank sensor, connect feed pins 1 and 2 together with a piece of wire, and test continuity of them both together at the ecu end.

For the unplugged cam sensor signal feed, if your piece of wire will reach, leave one end on the crank sensor pin 1 or 2, connect the other end to pin 2 of the cam sensor loom feed, test them both together at their ecu ends. Can do the same for the knock-sensor (signal pin1, earth pin 2).

Once you know you have one good wire that runs exclusively to an ecu pin, you can test at the ecu with that wire/pin and whichever other wire/pin is of interest.

[Robsey]

Being of the X prefix emissions type engines, the ECU wiring is more complicated than the earlier C prefix emissions looms.

My C20NE loom was far easier to assess, repair and reconfigure than my friends' X20XEV loom.

I am pretty good with wiring, but the XEV was a nightmare to work on.
Maybe if I had been more familiar with it, it may have made more sense to my tired old grey cells.

-----------

Recapping from the start -
The Crank-Angle sensor and it's cable are in the worst possible location to leave them vulnerable for failure.

Try unplugging the sensor, near the engine mount.
Give it a clean, and gently wiggle it back into it's location to ensure it is clean and properly seated.
Bolt it back in place but do not overtighten and crush the plastic fixing lug, as that would twist or skew the sensor out of alignment.

The other check is the other end.
Make sure all the pins are clean and dry, and if visible, all insulation is present and intact (looks in good condition).

That finally leaves the cable itself, which wraps it's way around the periphery of the timing belt covers.
Clipped into the plastic moulding of the casing, it should be routed clear of any moving parts and thus all outer insulation and the ground screen should be intact.

It is odd for a sensor to fail unless it has been knocked, damaged or made dirty by contaminants thrown off the crank shaft.

[thomas]

A trawl through the forum has unearthed a fuzzy schematic, and via postimage a slighly higher-res one
Still too indistinct in parts to distinguish wire-colour lettering, and without key-pages for it.
Expect many of the P-codes to be the same thing functionally, except the actual things are quite different from the c20xe items with the same P-code.

If P46 is still the Knock-sensor, then it appears to have three wires, earth 3, and two straight to the ECU K69.
So much is different, cam, crank-sensors etc. that using the C20XE diagrams is no longer useful.

edit:
Found the Calibra manual I seen the boxed-in subframe picture in.
Has wiring-diagrams: Early models, no XEV; Late Models, XEV but Simtec 56.5, not 56.1.

[Robsey]

Was the diagram from this thread?

http://www.vauxhallcavalier.com/forum/v ... 15&t=17223

I will see if I can get a better image.
The colour codes are quite simple to work out.

Remembering that they are two-letter abreviations for the colour in German.

BL = BLAU / BLUE
BR = BRAUN / BROWN
GE = GELB / YELLOW
GN = GRUN / GREEN
GR = GRAU / GREY
RT = ROT / RED
SW = SCHWARTZ / BLACK
WS = WEISS / WHITE

[thomas]

I think it is. There is so much difference between 56.1 and 56.5 we'd be better using the multec or motronic wiring diagram.

The crank sensor does look different for c18nz and c20ne, from xev, different again between xev 56.1 and 56.5.
Cam-sensor different from xe.







Rather a lot of Grey/Black. Grey/Red?

Park these here, to see what the big issues/differences are. 56.5 is fuzzy too, but wire-colours more readable, key pages might be useful.

[vexorg]

The ecu itself could be faulty, it's not unknown for them to just go bad.

The engine earths are another obscure one that gives very odd effects, make sure they are all good and clean.

[Robsey]

The problem with the ECU, is getting a suitable replacement.

Firstly because the ebay market is flooded with Vectra-B 'RT' ident ECU's.

Second is needing the whole caboodle to go with the ECU, unless you can program in the new ECU with Tech 1 or Tech 2.
Minimum need is the ECU, transponder chip... and maybe the Immobiliser pick unit.

[thomas]

It's all reminding me why I was seriously looking for a Chevette, in 2019. Bonus was, it would have shared parts with the Viva.
Tuning equipment was spark-plug socket, Gunson's Colortune and a big black umbrella. Some things need to be done in the dark.

Buy the book, there's no substitute for a paper copy you can thumb through.
Buy the companion books from Haynes (they're the best we've got, a desert without them) Diagnostic-fault-code manual etc. for this era of car.
If they'd do manufacturer and period specific books, we'd lap them up.

Buy some inexpensive test equipment, like we start with rubbish tools and appreciate the better ones, then get more selective.
Make some custom test equipment from parts being discarded, be it lengths of wire, cut-off plugs from component leads, or loom pieces and sections.
That you can tap things without mauling connectors or poking pointy probes through good insulation and some of the cores.

[ilovedmymantas]

Thanks for giving me more to worry about guys, you've given me a lot to think about

`I've been looking around the interweb for a dummies guide to testing while waiting on a new lead kit arriving. This is the site I settled on, it has a part about testing GM sensors. https://electronicshacks.com/how-to-tes ... ultimeter/

Can anyone tell me the pin colours for P35 on the simtec 56.1 schematic? My best guess for 1 2 3 doesn't sound right ( grey/black, grey/red, brown/red).

So many questions.
Can I do a continuity test on loom wiring without disconnecting the ecu for example? Not a clue