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Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle - Fixed #

Posted by Adam Critchley on January 15, 2014, 11:02 am

Year of Manufacture *: 2009
Engine Size and Code *: Z16xep
( Optional ) Scanner Used: Tech2, Bosch kts

Recoverd in by Rac erratic revs
No fault codes present

It initial revs high at roughly 1900 rpm then settles to 1400rpm

Once revved idle is the erratic bouncing from 9-1300rpm

I've found that If aircon is switched on it idles nicely at 800 ish rpm

Initial thoughts where vac leak fuel trims show to be ok
Short - 0 and long 8.6 when its revving erratically

Map sensor seems ok intake 39kpa when idling ok with aircon jumps about from 40-52 when revving erratically

Coolant temp is reading ok
Throttle position. 4%

I've removed cleaned throttle body on the off chance
And still the same

Went round intake manifold with Brake cleaner to check revs don't change
Removed oil cap and still same

O2 obviously erratic too when engine is erratic
When aircon pressed an revs stabilise
Sensor 1 reads 742.2Mv and sensor 2 reads 232.4 mv for a short period

Then rear shoots up to 722.6 mv and stays reading that for a short period before going lean and reading 195.4mv

Could this be fuel related?
Anyone had anything similar?

Re: Zafira z16xep erratic revs

Posted by Chris Angus <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5111' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 12:52 pm, in reply to "Zafira z16xep erratic revs "

I had something similar a while ago, was after we had changed the lambda sensor during an exhaust job, turned out we was supplied the wrong one. I would never have thought it would cause this.
Has any work been done previous to this fault?

Re: Zafira z16xep erratic revs

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 3:17 pm, in reply to "Re: Zafira z16xep erratic revs "
Adam Critchley

Nothing carried out recently had a coil pack and plugs in May
Had a service last January and is booked in for service MOT next week

Re: Zafira z16xep erratic revs

Posted by andyhyoung <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 5:34 pm, in reply to "Zafira z16xep erratic revs "
Andrew Young

I looked at one of these just before christmas ,with exactly the same symptoms.Also carried out similar tests with no positive results.One thing I did notice is a light "clacking" noise in the cam cover area,so I wonder if it is a breather related problem.Unfortuntely the customer did not want to take it any further (surprise?)so no nearer a fix.

Re: Zafira z16xep erratic revs

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 8:47 pm, in reply to "Re: Zafira z16xep erratic revs "
Adam Critchley

I've not noticed any unusual noises

A bit of a loss where to go next with it if I'm honest.
Customer wanted an answer the safternoon but what do you tell them other than still investigating.

Re: Zafira z16xep erratic revs

Posted by Bryan Smith <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5330' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 10:11 pm, in reply to "Zafira z16xep erratic revs "
Bryan Smith

Hi Adam,
Have you thought about mechanical issues? I would have thought the only thing the aircon would do is put a load on the engine. It sounds like you don't have a smoke machine so might be worth trying to borrow one (one of my best investments!) just to double check for leaks. Have you done a vac test with the engine running and/or comp test? Is the STFT just a default value? I can't see that being correct if the engine is hunting but someone may correct me if I'm wrong. LTFT at 8.6% does seem high but probably not enough to set a DTC and possibly settles when under load? Have you got any way of monitoring injector current and/or pulse width?
Sometimes we can't just give customers that immediate answer and if they are reasonable they will understand. I always tell them that work in the diary gets priority.
Hopefully that's given you some ideas on the next step.
Bryan.

Re: Zafira z16xep erratic revs

Posted by Alan Lange <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3293' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 10:14 pm, in reply to "Re: Zafira z16xep erratic revs "
Alan Lange

Hello Adam, double check its not pulling air via the breather system. New rocker cover will be required if it is. (common failure). Alan.

Re: Zafira z16xep erratic revs

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 15, 2014, 10:56 pm, in reply to "Re: Zafira z16xep erratic revs "
Adam Critchley

I've not compression tested it only hunts after first rev and with it idling ok with aircon I thought just the side of breathing problems

But fuel trims made me think maybe not
The long term goes to 0 when aircon turned on

Unfortunatly don't have a smoke machine have manager that's not really interested in spending out but wants all the answers ! But that's another topic. I did try and make one a couple months ago but couldn't get enough smoke out.

The kts has a built in scope it's not very good but may reveal something.
Will try hooking my amp clamp on see

Yeah that's problem bookings always come first so on and off job constantly

The rocker cover sounds like a good idea will check again in the morning

Re: Zafira z16xep erratic revs

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 16, 2014, 10:18 am, in reply to "Zafira z16xep erratic revs "
Adam Critchley

Just managed to get vac guage Teed in

Engine steady idle but at 1500rpm
Showing 20inhg

Snap throttle goes to 0 and down to 25inhg before settling back to 20inhg

Once hunting starts the vac guage also bounces between 15-18 inhg

Snap throttle still sane as previous

Aircon turned on a steady idle at 800rpm
Vac gauge reads 18 inhg

Would this point to mechanical engine issues?
Valves or what ever ?

Re: Zafira z16xep erratic revs

Posted by Shane gray <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3442' width='330' height='300' border=0 style='border:none;'> on January 16, 2014, 7:51 pm, in reply to "Re: Zafira z16xep erratic revs "
Shane Gray

Had a meriva in today with simailer symptoms. It was revving erratically , this turned out to be EGR valve. I also had no fault code. I was lucky to have a valve in stock ready for another car so popped it on to try!
Hope this helps.
Shane

Re: Zafira z16xep erratic revs

Posted by Bryan Smith <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5330' width='330' height='300' border=0 style='border:none;'> on January 16, 2014, 8:54 pm, in reply to "Re: Zafira z16xep erratic revs "
Bryan Smith

Hi Adam,
The vac on snap throttle sounds about right but not sure about the bouncing when the engine is hunting. I would think that's just a symptom?
The 18" when idling and aircon switched on seems a bit low but I have seen engines that are running perfectly show similar readings. Their is plenty of info on the net on good and bad vac readings so might be worth a look. If your boss want's results he needs to make some investment. A smoke machine is not what could be called a major outlay and it would have confirmed or eliminated an air leak in minutes. See if you can borrow one so he can see what it will do (your Snap On dealer may know someone that could let you have one as a demo). Shane's suggestion also sounds viable.
Bryan.

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 19, 2014, 11:58 am, in reply to "Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Adam Critchley

Well doesn't look like I'll ever know about this one

I left that garage on Friday start my new job tomorrow
Spoken to one of the lads from old place today and he says the zafira is booked into dealer tomorrow

Re: Zafira z16xep erratic revs

Posted by paul goswell <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5240' width='330' height='300' border=0 style='border:none;'> on January 19, 2014, 12:05 pm, in reply to "Re: Zafira z16xep erratic revs "
Paul Goswell

the clacking noise in the inlet could be the baffle plate inside the inlet manifold the are little torx screws which come loose could cause idle problem

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by Bryan Smith <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5330' width='330' height='300' border=0 style='border:none;'> on January 19, 2014, 12:51 pm, in reply to "Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Bryan Smith

If your boss wouldn't even spend on something as basic as a smoke machine its probably a good move.
Good luck with the new job.
Bryan.

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 20, 2014, 7:09 am, in reply to "Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Adam Critchley

Thanks Bryan

There's no saying this one boss is going to be any better

But nothing ventured nothing gained hey?

It's closer to home so can save some cash on traveling costs if nothing else

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by andyhyoung <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on January 21, 2014, 8:45 am, in reply to "Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Andrew Young

I wonder if it would be possible to follow the progress of this car at the dealer.How many parts are they going to throw at this before they reach a fix?Curious to find an answer here.

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by Adam critchley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3657' width='330' height='300' border=0 style='border:none;'> on January 21, 2014, 11:09 pm, in reply to "Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Adam Critchley

I'll post up any info I get

Like you say don't know what they'll throw at it.

But ill keep asking the lads to update me on it

Fixed #

Posted by Adam Critchley on January 24, 2014, 7:10 pm, in reply to "Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"
Edited by board administrator January 28, 2014, 3:08 pm

Update on this guys

One of lads has told me vauxhall performed a software update and that sorted it

Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #

Posted by stefan coleman <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3676' width='330' height='300' border=0 style='border:none;'> on February 3, 2014, 4:14 pm, in reply to "Re: Vauxhall Zafira 1.6 Z16XEP 2006 - Erratic idle #"

I have had the same fault a few times...have the engine ecu reflashed with latest software this should do the trick. If you have vaux com, check data lists, if you see idle speed modified as YES it may not work. I had one like this and it needed an ecu.

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