Zafira cam timing, what have I done wrong?

[lisbon_road]

05 plate Zafira, selling for a friend who has emigrated (but my wife has taken a fancy to it).

 

Changed cambelt and bits, won't run right - doesn't idle smoothly, no power at all, and revs shoot up occasionally.

 

I believe that I have set the timing correctly - mark on crank, 3 o'clock and 9 o'clock on cams.  Can't see being a tooth out would do that and I am sure it isn't a tooth out.

 

No MIL.  Tried moving the cam sensor out as that has been disturbed but that didn't make any difference (apart from setting off the MIL).

 

So, what dumb arse thing have I done please?

[red5]

Engine? I'm guesssing you checked marks after fitting new belt before cranking it over?

[lisbon_road]

Yes - crank on the mark and cams on quarter to and quarter past.  Put the marks so they are close together on the cams, I have checked it on the manual and the internet.  It is a 1.8, no idea the code, but before they want all fancy with VVT and stuff.

[bub2006]

Z18xe or z18xer if its vvt. 2005 was the changeover i think when the zafira and the vectra was facelifted they got the vvt engine. Its timed up correct by the sounds of it so i would hazard a guess on a sensor throwing a hissy fit

[lisbon_road]

The only sensor I have disturbed is the cam sensor, and I tried disconnecting that and it didn't make any difference (though the MIL came on).

 

Perhaps I should read fault codes or disconnect the battery for a bit?

[twosmoke300]

What about the maf sensor on the air filter ?

[lisbon_road]

I have not touched the air flow meter (or whatever it is) in the pipe just down from the air filter.  I did replace the airfilter element and the old one was black.  Is there anything else?  No wires to the air box.

 

Still, an idea, could have a look and see if there is any chance I have disturbed it.

[red5]

Sounds like timing is out to me. cam sensor would run ok up to 3000rpm then stop.

 

Check the belt timing again - you used the mark on the crank pulley that points to '25 past' ?

[Lankytim]

I recon its a couple of teeth out somewhere.

[lisbon_road]

I checked the timing loads of times, and wound it round loads of times. I did wonder if I'd got it miles out simply by using the wrong marks or something but I have looked in loads of places and always get the same answer, including the 25 past.  Been suggested elsewhere that it could be an airleak with the pipe fitted to a solenoid on the back of the airbox.  I think that is a good call, real airleak symptoms.

[philsford]

Did you put your own marks on before you removed the old one or are you using factory marks? I did my old 03 plate 1.8 one by marking it up myself no problem at all apart from having to helicoil a bolt on one of the pulleys.

Sounds like the timings out to me.

[DaveAspley]

If it's a z18xe1, the cams WILL move unless locked with the appropriate tool. Springs off mark like a mofo. The tool was an essential thing to buy as a Vauxhall Technician (99-07) , are you midlands? I still have the cam lock tools and it takes me 25 mins tops to change (or in this case time up) a zafira belt. Also, check there isn't any vacuum hoses adrift.

[DaveAspley]

Or if not, a cam lock tool is a tenner....

[lisbon_road]

FIXED.  Was the pipe from behind the airbox to the throttle body, come adrift at the throttle end.  Looks like it would come off really easily. 

 

Always good, you fix it, and suddenly it works.  Then you forget all about it and move on to the next issue.

 

Thanks for the ideas.