GUIDE : Changing your cam position sensor on an X20XEV 2.0 Vectra

[JSeaman]

All of a sudden our engine warning light came on and the rev counter started dancing about all over the place. The engine would then cut out and stall. Upon restarting the engine it would keep the engine warning light on and then drive OK (some kind of limp home mode I guess where the cam sensor is ignored)

My instant assumption was cam position sensor and a check of the error codes using the paperclip method revealed a cam position sensor error. Some digging around has shown this is a relatively common fault and can be quite easily be rectified by your average home mechanic. Whilst doing this it is worth doing the cam belt too if it's approaching the interval although for me this wasn't needed so sadly I've only done a guide for the sensor.

For me it cured the problem completely and hopefully it will be the same for you. I suggest you do the paperclip test to confirm it is your problem (and importantly your only problem!), and then get on with following the guide, good luck!

Step 1 - Pop your bonnet. If you don't see an X20XEV as in this picture then don't follow the guide!
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep1.jpg
Step 2 - On the left hand side (driver's side) you'll find the airbox which houses your air filter. There are half a dozen metal clips that simply pull out and drop down to separate the 2 halves of the box, undo them all
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep2.jpg
Step 3 - Undo the flathead screw for the jubilee clip - just enough so the jubilee clip spins round freely
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep3.jpg

[JSeaman]

Step 4 - Remove the large air hose (wiggle from side to side a little if it's difficult) from the airbox

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep4.jpg

Step 5 - The top half of the airbox should come away easily now

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep5.jpg

Step 6 - The yellow filter is your air filter which you can simply pull out and put to one side (replace it if it isn't a bright yellow)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep6.jpg

[JSeaman]

Step 7 - Undo the screw on the jubilee clip at the other end of the large air hose for better access

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep7.jpg

Step 8 - Then remove the wiring to the sensor by squeezing the metal clip and pulling up

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep8.jpg

Step 9 - Remove the air hose completely now

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep9.jpg

[JSeaman]

Step 10 - Remove the airbox from the car (see next step), it will take a bit of wiggling

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep10.jpg

Step 11 - The first two pictures show the mounts for the airbox. The third picture shows the base of the air box where two 10mm nuts/bolts should hold the airbox down. Mine were broken but if yours aren't you will need to undo them before the box can be removed.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep11a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep11b.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep11c.jpg

[JSeaman]

Step 12 - Place a trolley jack under the car and take the weight of the engine with it. I just put it on the sump, you would never jack a car up using the sump but this is just to support the engine when you remove the stay in steps 13 and 14. Leave it jacked up until you complete the job. As soon as the engine starts to rise stop jacking.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep12.jpg

Step 13 - Using a 16mm socket, undo the three large bolts holding the stabaliser in place (some vehicles won't have this fitted)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep13.jpg

Step 14 - Once all three bolts are removed the metal stay will be able to come away from the side of the engine

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep14.jpg

[JSeaman]

Step 15 - Moving to the other end of the stay, undo the 16mm bolt beneath the brake fluid reservoir

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep15a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep15b.jpg

Step 16 - Slide the bushing out and twist it vertically so you easily remove the whole arm from the car

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep16.jpg

Step 17 - Examine the bush for signs of damage and wear. Mine was seriously split and needed replacing (About £30 from Vauxhall)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep17.jpg

[JSeaman]

Step 18 - Look for 10mm bolts holding the cam belt cover to the engine. I found most of my bolts were missing but I've shown the one fitted next tot he three 16mm bolts removed for the engine stay

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep18.jpg

Step 19 - this is to show what happens if you don't put the bolts in. I had this much play in my cover

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep19a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep19b.jpg

[JSeaman]

Step 20 - We need to remove the auxillary drive belt (fan belt or serpentine belt) before the cover comes away completely. This also gives better access to some of the bolts. Make a note of the routing of the belt before taking it off.

Picture 1 - shows the route at the top of the engine over the pulley towards the alternator.

Picture 2 - Shows the belt from the first pulley over the alternator pulley and then heading down towards the floor

Picture 3 - From the alternatorm, the belt goes down to the idler pulley/tensioner and passes over the side nearest the front of the car before heading to the bottom pulley

Picture 4 - Not a great picture but it goes from the idler pulley back over the crankshaft pulley before heading round and back to the water pump pulley

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep20a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep20b.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep20c.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep20d.jpg

[JSeaman]

Step 21 - Put a 15mm spanner over the nut on the tensioner and rotate it clockwise (pulilng the spanner towards the front of the car). This will slacken the belt so you can slide it off one of the pulleys (I chose the alternator)

Note that you don't need to remove the belt completely and it's easier to let it drop down over all the other pulleys so you just slide it back on the alternator when you've finished. This way you don't need to remember the routing!

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep21a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep21b.jpg

Step 22 - Now we have improved visiblity we can gain access to the other 10mm bolts holding the timing cover on, remove these

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep22.jpg

Step 23 - With some serious wriggling (careful, it's not the strongest plastic in the world) you can remove the timing cover although it looks like it would have been easier by removing the bottom crank pulley so you may choose to do this (If so, I recommend putting a 17amm socket and breaker bar on the bolt, wedge the breaker bar against the ground then turning the engine over on the starter to crack off the bolt)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep23.jpg

[JSeaman]

Step 24 - It's worth rotating the crank (use a 17mm socket) until the matchmarks on the camshaft pulley are aligned with the grooves in the bacplate for the timing belt (as shown in the second picture) just to check the marks match correctly and the belt hasn't skipped a tooth out. Also, check the belt isn't too loose or tight by flexing it with the fingers (don't twist it though)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep24a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep24b.jpg

Step 25 - Now onto the sensor itself. A single 8mm torx bolt holds it on so you'll need a little socket as shown in the first picture. You'll have a clear view of the sensor now behind the two cam pulleys (picture 2).
Remove the single torx bolt as shown in picture 3 to release the sensor.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep25a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep25b.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep25c.jpg

[JSeaman]

Step 26 - Now up top and remove the two allen key bolts holding the spark plug cover in place

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep26.jpg

Step 27 - With the cover removed you will have access to the sensor from the wiring as shown on the left hand side of the picture

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep27.jpg

Step 28 - The sensor should freely pull clear and out through this hole by gently pulling the wire as shown

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep28.jpg

[JSeaman]

Step 29 - Speaking to my local Vauxhall dealer I was told that the crank and cam sensors on these were regularly replaced for a while until suddenly a new part number came in and the sensors were sold ith a differen connector. It looks like the connector must have been part of the cause for the cps (cam position sensor) failing so you shoud switch to the new one.

What this means is that rather than buying a £15 ebay part it's worth stumping up for the £48 odd Vauxhall charge because they give you a new connector and pigtails of wire.

Drop the new sensor in the same hole you removed the old one from (note the wiring is all loose at the moment) and tighten the E8 torx bolt

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep29.jpg

Step 30 - Refit the HT lead/spark plug cover being careful not to damage the boot of the wiring

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep30.jpg

Step 31 - Refit the cam belt cover and ensure all the 10mm bolts are fitted

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep31.jpg

[JSeaman]

Step 32 - Make sure the fan belt is routed properly as described earlier (if you didn't remove it completely then just pick up the lose wire and jump to the next step, makes it much easier)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep32.jpg

Step 33 - Again onto the tensionser although this time I recommend you use a 15mm socket. A 1/2" drive will be too big to fit in but you need to put some force on so 1/4" drive is perfect. Again, rotate the pulley towards the front of the car (clockwise) all the way forward -there's quite a lot of travel- and then slide the belt over the alternator pulley. Two people might make this bit easier but I just rotated the pulley all the way forwards with both hands then held the ratchet with one hand whilst sliding the belt over with the other, not too difficult really.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep33.jpg

Step 34 - Refit your stabiliser arm (with a new bush in my case). Put all the bolts in finger tight and then use the socket so you know all the joints are in the right place (it pivots so you need to get everything lined up before tightening)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep34a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep34b.jpg

[JSeaman]

Step 35 - Refit your air box and the two blts i they are present

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep35.jpg

Step 36 - Drop the air filter back in as shown

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep36.jpg

Step 37 - Pop the airbox cover back on and do up all the clips

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep37.jpg

[JSeaman]

Step 38 - Refit the air hose again and do up the screws for the jubilee clips

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep38.jpg

Step 39 - Plug your sensor back in (I assume it's air temperature)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep39.jpg

Step 40 - Now you're pretty much back where you tarted from except you have a load of wires sticking out where you once had a nice single piece of wire, time to fix that...

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep40.jpg

[JSeaman]

Step 41 - The sensor comes from Vauxhall wth 4 crimps, throw these in the bin. You do not want to crimp these wires, they should be soldered. Speak to a Vauxhall technician and they will tell you the same.
First, cut the existing wire leaving yourself penty of slack. In my case the wire had already been joined (someone had done a pretty rough job of doing exactly what I'm about to do), butI ignored this and snipped just before the old repair

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep41.jpg

Step 42 - Get some of these wre strppers, you can get them in places like Maplin forabout £10 and they are ace. Strip th4 wires on the ed of the sensor lead you just boht

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep42.jpg

Step 43 - Your stripped wires should look something like this (don't show too much metal)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep43.jpg

[JSeaman]

Step 44 - Twist the ends of the wires so you don't have any strands sticking out and neaten them up

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep44.jpg

Step 45 - Do the same to the wires from the old wiring where you snipped with the scissors (obviously remove some of the black outer sheath to reveal the wires then strip the insulation off the wires).

At this stage I would normally put some heat shrink down one side of the wiring and solder inline then heatshrink around it but I knew I didn't have any heatshrink so just twisted them together, soldered and applied heatshrink after I'd gone and bought some. You can do it either way.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep45.jpg

Step 46 - Get a good hot soldering iron (especially outside and even more if you are doing it in the snow like me!), and solder each of the pairs. The trick here is to get a nice hot soldering iron, dab the tip with some fresh solder then hold the tip against the wires while feeding in some solder from the opposite side of the wire. Impossible to photo me doing it on my own but hopefully that's clear.

You should end up with something similar to the second picture. It doesn't have to be a work of art but make sure you've got a good solid join and well covered in solder.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep46a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep46b.jpg

[JSeaman]

Step 47 - Now for the heatshrink, this will provide insulation between the pairs of wires and also seal out moisture and oil. Use the smallest heatshrink you can to fit over the wires (Should cost about £2 from B&Q etc for an assortment of heatshrink)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep47.jpg

Step 48 - Cut it into lengths sufficient to cover the wire as shown

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep48a.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep48b.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep48c.jpg
http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep48d.jpg

[JSeaman]

Step 49 - Now use a heatgun to make the heathsrink shrink (surprise!) and seal around the wire pairs. If you do the wires inline (i.e. one wire leading straight into the other as opposed to the twisting affair shown here) then it will make a good seal and you can leave it at that.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep49.jpg

Step 50 - Once heated they should look something like this

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep50.jpg

Step 51 - Fold the tips over so there's no chance of moisture getting in (it should seal below this anyway)

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep51.jpg

[JSeaman]

Step 52 - Now wrap the whole lot in plenty of insulation tape to keep them all together and nicely protected. Use plenty of tape and keep it nice and tighte.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep52.jpg

Step 53 - Tuck the wiring away and enjoy some trouble-free driving.

http://img.photobucket.com/albums/v312/JSeaman/Vectra/CPStep53.jpg

Comments/suggestions welcome

James

[mikevec]

followed your photo guide today. excellent!!!. thanks for the advice. now running sweet again. One comment, I only found the link by searching "E8 bolt vectra" on google. previously i was searching "camshaft sensor fitting" for 2 days. glad I found it. thanks.

[JSeaman]

Hi,

Glad the guide helped you - hopefully the mods can move this to a place that's easier to find?

Cheers

James

[Schumatter]

I couldn't find it either till I googled how to change a cam sensor . Anyway it's a brilliant how to , well done .

Do you know if this Sensor from LMF is ok or do I need the whole thing with wires ?

http://www.lmfvauxhall.co.uk/store/product.php?productid=16364&cat=0&page=1

[JSeaman]

The wiring's the important bit apparently - the connector allowed water ingress so people were changing their sensor only for it to fail again

Glad it helped you - maybe someone could put it in a more accessible place?

[thepeachroom]

Does anybody know the vauxhall part number for the replacement cam sensor cable? Mine is falling apart and as above there is an updated replacement part from Vauxhall that you have to solder on yourself. If I have the number I can order it, my local VX dont know about the replacement part.

[mrcarot]

Cheers. Most helpfully...

[MarkWC]

Sorry to bring up an old thread but I have to carry out this change on my Astra G 2.0 16v X20XEV as it has developed a problme of not wantign to start every now and again while throwing up the engine management light.

I got one of the modified sensors but comparing it to the colour of wires I ahve on the car already they do not match up. Is there a list of what colours do what on each wire on the original loom and on the modified loom.

Thanks

Mark

[JSeaman]

I'm afraid that's one I can't help with but contact the tech guys at your local Vauxhall dealer and they'll be able to help you out

[ainux]

the photo guide excellent!

[JSeaman]

Glad it helped you

[byrnecut]

I would have changed all the belts once i got that far

[squellie]

Any IDEAS HOW EASY IT IS TO CHANGE A COIL RAIL FOR VECTRA 1.8LS

[lukefenech]

Excellent. Unfortunately I ordered a generic non-genuine replacement sensor before I managed to find this post. Otherwise I would have got the genuine one. Might see if I can waterproof it a little bit when I put it on.

Kind regards and once again, it would be really helpful if this was moved to an easily "searched" location.

Luke

[JSeaman]

Good luck with the waterproofing Luke!

Could someone please sticky this or something so people can find it?

[Dee_123]

I've just purchased a new camshaft sensor with the lead off ebay, item number 160352132984. Only thing is it look different to the one you've got. Well the wires aren't the same colour and i've got a red wire, yellow, black and one wire with heat shrink around it? Any help would be much appreicated ;)

[barrycam]

Hi James,
Today I helped my Son in Law with his 1999 2.0 vectra.I printed your very clear guide and put it into a multi sleave folder. We cannot thank you enough for producing it. I don't think we would have attempted this work had I not found your Guide on Google
cheers Barry

[JSeaman]

Thanks Barry and I'm glad it helped you

Dee - have you sorted your wiring?

[fathimq1]

thank you Jseaman for this ever so much , I have paid quite a sum recently for mechanics to tell em that i have a camshaft pos sensor error , and non of them suggested replacing the sensor. using your excellent guide here I was able to do this my self . ok it took half a day .. and the wife said o would never be able to assemble it all back together , but..! I did and the sensor error has finally dispeared . my mechanic was go smacked . Thank again

[JSeaman]

:) Good for you - really glad it helped you, well done!

[fathimq1]

Unfortunately my camshaft sensor error has returned , i am so frustrated , my mechanic thinks that the new sensor maybe faulty , but I double checked the risistance between the sensor plug inputs .. the old one was definitely faulty and the new one ok. I now get an error as soon as I turn the key one notch .as soon as the engine starts running and for about 4 second the error dissapears , then re-appears again..help

[JSeaman]

The likelihood of a sensor failing is slim (but possible), my money would be on a wiring fault. Try and trace the loom back as far as you can and look for shorts/cracked insulation etc.

[mint]

What this means is that rather than buying a £15 ebay part it's worth stumping up for the £48 odd Vauxhall charge because they give you a new connector and pigtails of wire.

Have the sensors changed? Or is it just the connector? I phoned Vauxhall today and they quoted me just over £100 for a new sensor with new connector! :cry:

[JSeaman]

The connector was the change, the new part number simply had the old sensor with the improved connector and pigtails, £100 sounds a lot - try another dealer to be sure you aren't being overcharged!

[mint]

So you got the sensor and connector for £48?

[JSeaman]

Yes that's correct, both came together

[fixitsnoops]

my car is 1.6 vectra ,but i have got to say what a fantastic illustration and explanation of a diy repair, which no doubt will help someone greatly! and also give them the confidence needed to tackle other projects , ( brilliant well done james )

[JSeaman]

Many thanks, hope it helps

[fathimq1]

ok I finally got the original sensor of a scrapped vectra , worked straight off and has now for 10 days i cant believe the merry go round i have had just because no one suspected that a new sensor could be faulty and it was , it turns out the part I thought was genuine was not , and i am having trouble getting my money back. (50$) , will teach me to buy stuff from any old parts shop next time.

[JSeaman]

Oh dear! Always suspect everything I guess but I'd have gone for wiring - glad you sorted it it though, I sitll recommend genuine sensors :)

[mahler]

In post number one the author says
If you don't see an X20XEV as in this picture then don't follow the guide!I need to change the cam sensor on my 1998 1.8 Vectra Ecotec X18XE so does that mean the excellent guide can not be used for my job, and if that is so what differences are there in the procedure between the two engine types.

Thanks and regards mahler.

[JSeaman]

Sorry Mahler, I'm afraid I really don't know the range well enough to tell you. They may be identical, they may be very different! I know that doesn't help you much but I'd suggest you have a look in case they are the same

[mahler]

Sorry Mahler, I'm afraid I really don't know the range well enough to tell you. They may be identical, they may be very different! I know that doesn't help you much but I'd suggest you have a look in case they are the same

Thank you for your reply JSeaman, and it's amazing to think that with 18923 thread views they are all only interested in the X20XEV engine, but as you say I'l open the bonnet and have a look if all the written details compare correctly.

Best regards mahler.

[JSeaman]

I gues the X20XEV is pretty popular :) For what it's worth, the CPS is going to be fairly similar on all cars - usually located in the same sort of place with the same sort of sensor and wiring so with a bit of luck you'll manage with the guide and a bit of innovation! Best of luck with it

[barrycam]

HI,
last year I followed your guide for the the cam position sensor. and did thank you for your help.
this years problem is a broken front spring on my son in laws 1999 vectra hatch 2.0 ltr.
do you know of a similar guide to yours for fitting a new front spring
regards
barry pearson
barrycam