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Gary
Gary, Australia Car Mechanic
Category: Australia Car
Satisfied Customers: 839
Experience:  Senior Technician
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I am looking Captiva specialist. The z20s diesel. My car has

Customer Question

I am looking for a Captiva specialist. The z20s diesel.
My car has an intermittant stumble/miss.It idels away nicely for about 15 seconds then brakes into this stumble. It will stumble for about a minute then idels nicely again. It started as a small miss but is now significant.I have run out of options.
The timing belt was replaced, the injectors have been replaced. The cpu has been replaced. The engine wiring harness has been replaced. The fuel filter and canister has been replaced. Both crank and cam sensors have been replaced. The airflow sensor has been replaced. Compression has been checked. The exhaust has been checked for back pressure and a regeneration has been forced to be sure. The air filter changed. The air conditioning has been checked
The car was fine for the first 3 years and now the holden dealers gold cert mechanics are shaking their heads.
Submitted: 1 year ago.
Category: Australia Car
Expert:  Gary replied 1 year ago.

Hi there,

I am a Gold Certified tech, so I'll see if I can help you further.

I'm sure by your description, they have done all the normal things, so I'll throw some more ideas at you.

Can they isolate the miss to one cylinder by disconnecting each injector in turn?

At that point, it will miss on one cylinder only, if it misses intermittently on 2 cylinders, then the one they disconnected is not the cause. They need to find where with one disconnected, it only misses on that cylinder.

When they did the ECM replacement, did they do ALL the programming and setup procedures?

Compression may be ok, did they perform a cylinder leakage test?

Have they inspected the camshaft and roller rocker arms for wear/damage?

Have they taken a fuel sample and checked for any water?

Have they checked the low pressure pump supply pressure?

Gary

Customer: replied 1 year ago.
Injector 4 was the furtherest out of speck and i believe has the miss as well, out of spec based on a return flow test. They replaced them but there is no difference,in fact in my opinion the problem is worse than when they were given the car.
I dont know about the cylinder leakage,i will call tomorrow.
We got a used ecm and i supplied yhe spare key, but with no different they put my ecm back in.
07 captivas are now on recall since Dec 2015 for a needle roller issue with the camshaft and they assured me the engine had the work done.
The fuel sample was good. They changed the fuel filter in the vehicle and managed to crack the canister in the process, They told me it was leaking when it came in!
Another $280.00
They have checked all the fuel pressures.
The miss isnt as bad at higher revs. Anything about 2000 and it evens out. Could it be the throttle electronics?
Expert:  Gary replied 1 year ago.

Hmm, it seems it is worse after replacing the injectors.

My bet is the injector seats (inside the cylinder head) were not cleaned well enough, and/or the injectors are torqued correctly.

And did they get the injector programming correct with the 20 digit programming code that is printed on the injector?

Have they also checked for any boost pressure leaks etc?

Once above 2000 rpm, how well does it perform?

Does it have the torque/power that it would normally have?

It would log a code and illuminate the engine light for throttle electronics.

There is a techline for a revised X101 harness bypass.

Gary

Customer: replied 1 year ago.
The engine light came on soon after leaving their workshop. There is another garage in town i may approach next week for a diagosis and see what they think. Im going to issue a complaint to fair trading for the dealers incompetence once i know the cause.
Expert:  Gary replied 1 year ago.

In a way, that's good news.

I can help you from the engine code set.

I'll wait for you when you get that.

Gary

Customer: replied 1 year ago.
Ok ill book the car in tomorrow and be back in touch.
Expert:  Gary replied 1 year ago.

Ok, all the best for tomorrow.

Don't pay too much for diagnosis, as long as they can give the code for now.

Gary

Expert:  Gary replied 1 year ago.

Hi again,

How did you go with Holden?

I hope my advice has been of assistance to you.

Regards

Gary

Customer: replied 1 year ago.
I am going to Supercheap in Tamworth tomorrow for a diagnostic, so I should have some codes tomorrow afternoon hopefully. The engine light has gone off now but they can read the code history anyway.
Expert:  Gary replied 1 year ago.

Here from you soon.

Can't wait for the code that would be stored as history.

Hope the dealer will have egg on their face, if you return the vehicle with more info, regarding their possible workmanship error etc.

Gary

Customer: replied 1 year ago.
P0544 exhaust temp sensor -voltage too high
P2452 particulate filter differential pressure sensor -voltage too high
P2031 exhaust gas temperature sensor (bank1,sensor 2)-voltage too high
P244B particulate filter Differential pressure sensor-differential pressure too high.
Thats all that were in the history. Some may have been triggered when i was changing sensors.
Expert:  Gary replied 1 year ago.

Ok.

A few things.

I would clear the codes, AND NOT touch anything until the engine light reoccurs.

Then we'll act on what codes are real rather than man-made.

The one thing that I have seen many times is when the engine is cold ALL temp sensors should read equal to ambient temp, ie: 25 degrees C.

I've seen a few Captivas where the rear temp sensor will read 112c when the rest read 25.

The ECM is faulty in these cases.

With a new harness I doubt it is a wiring problem.

The rear EGT sensor harness is prone to damage from driving over foreign objects.

Let me know how you go.

Very interested in helping you fix this.

Gary

Customer: replied 1 year ago.
I cant reset the engine fault at the moment. I will have to take it to someone tomorrow locally.
Expert:  Gary replied 1 year ago.

That's ok, just let me know when the light comes back on.

The new code then needs to be reread.

Hope it does reoccur fairly quickly, then you can get a another scan.

Hope Supercheap is looking after you for diagnostic scan tool time.

Gary

Customer: replied 1 year ago.
$14 a scan
$28 to reset
180klm round trip to supercheap which makes it not so convenient.
Expert:  Gary replied 1 year ago.

I would do it for free, generally knowing you would come back for other repairs.

Hope to hear from you soon.

Gary

Expert:  Gary replied 1 year ago.

Hi again,

Have you had any success with clearing the codes?

If it reoccurs near the place you have the reset done, what code comes back?

Gary

Customer: replied 1 year ago.
They want $100 to clear the code here in Gunnedah. They will not be getting my business. I am planning to go to Tamworth on Saturday and then on to Nundle for the day. If the code is tripped i can hopefully get it read on the return journey.
Expert:  Gary replied 1 year ago.

$100, that's a bit rough, for 2 minutes worth of work.

Hopefully the Tamworth mechanic will look after you.

Wishing you a safe and happy easter.

Gary

Customer: replied 1 year ago.
just supercheap again. I have contacted Holden Australia and they have issued a case number. They should call the Gunnedah branch and then contact me for my deposition of events.
Expert:  Gary replied 1 year ago.

That's all promising news.

Hopefully something good comes soon.

Gary

Customer: replied 1 year ago.
I suggested the rocker issue, I gave them my vin and they tried to tell me that me car wasn't a part of the recall. I then told them my numbers matched and they then changed their tune. In may be mechanical after all.All the best for Easter Break. Where are you located just for interest sake?
Expert:  Gary replied 1 year ago.

I'm in Brisbane, northern suburbs (Everton Park).

Have a safe trip.

Gary

Customer: replied 1 year ago.
My brother lives in Annerley and some cousins are on the Gold Coast. I get up there occaisionally. Talk to you next week when i know more.
Expert:  Gary replied 1 year ago.

Ok, all the best, ***** ***** trips over Easter.

Gary

Customer: replied 1 year ago.
Gary. I may have had a break through. Yesterday i pull the glovebox out of the car and gave the wiring a bit if a wriggle to see if I could get any type of change.
Nothing. I put it back together and shut the car off,leaving the key in the ignition.
I went to bed at about 9.00pm. My wife woke me at about 10. She told me the captiva keeps starting up and shutting down on its own! Its done it 3 times in the last 10 minutes!
Sure enough. I went to the car,it was sitting there running with automatic lights on (it was actually really creepy) and i opened the door and checked the ingition,it was in the off position. I twisted it just the slightest amount anticlock wise and the engine shut off!
I pulled the key.It hasnt done it again.I went back to bed AND here i am with insomnia very excited and sending you a message at 3.00 am in the morning. LOL.!
It has to have something to do with the issue. What are your thoughts,Havw you heard of it happening before? What do I need to get to fix it? Keys,ingnition switch,immobilizer,door locks,holden dealer? I have the 3 parts cars in Tamworth and we are going past there later today.
I wont bother with the engine light reset just yet. Cheers,Tim
Expert:  Gary replied 1 year ago.

Hi Tim,

There is a recall for the ignition switch for that scenario.

Holden warranty should cover it.

Tell them how you told me.

Holden says it only happens in a manual transmission, which I think is BS.

Manuals will drive off if left in gear.

It won't solve your original fault, but needs to be done anyhow.

Let me know how you go.

Gary

Customer: replied 1 year ago.
Ok. I will get the faults reset in tamworth today.
Expert:  Gary replied 1 year ago.

Ok, that's good Tim.

Gary

Expert:  Gary replied 12 months ago.

Hi Tim,

How did you go with Holden?

Any further info?

Gary

Customer: replied 12 months ago.
They say my car is not covered by the recall on the ignition tumbler. I have told them to think about the safety implications if they deny the warrenty. I should get the desired result.
Regarding original problem.
The roller rockers where not inspected for degradation of the needle roller bearings and apparently no compression test or leak down has been done. They avoid it because the access is through the glow pug ports and is a hazard in itself. The plugs threads react with the alloy head and grow together,the plugs snap when being undone, the head then has to be removed and whole thing becomes a very expensive and messy affair.
It may be my only option apart from selling the car as is... i can do the work. I notice they have leak down testers on ebay anywhere from $40 through to $300.
Expert:  Gary replied 12 months ago.

Hi Tim,

I have read our conversation again, I see where you said the engine ran better before they replaced the injectors.

This says to me they were on the right path, but have not done the job correctly or one new injector has a intermittent issue.

Either way it should still be a parts warranty/workmanship issue.

What did they do this time regarding the engine codes?

This is not a job for you at home, they are many special tools for timing belt etc.

Gary

Customer: replied 12 months ago.
I was quoted $2500 to have holden do the timing belt. I bought all the tools, parts including seals and water pump and did the job myself for under $500.The car ran perfectly for 6 months and had good ccononmy. Holden did a check of the timing and adjusted one tooth on the fuel pump. The car runns no better and the fuel ecconomy is crap at 11.8/100ks.
A friend has offered a compression tester which i will pick up today I will test over the weekend. The engine computer hasnt tripped again since reset on Saturday. My wife is using the car daily.They talk about glow pluggs in each cylinder bat I cant recall seeing any. I will have another look on the weekend. I can remove the injectors and pipework and put them back so long as I keep everything matched. What are your thoughts?
Expert:  Gary replied 12 months ago.

Hi again,

That's interesting what you say about the High Pressure fuel pump.

The pump runs at 2/3 engine speed and although it has a timing mark, learning through Holden, it is common knowledge that the fuel pump timing is not critical. The camshaft is normally locked at the vacuum pump end, the crankshaft is locked with a pin through the side of the block.

The camshaft pulley bolt is torqued at the end of the procedure after the timing belt tension is set.

There is a glowplug per cylinder at the back of the cylinder head about where a sparkplug would go.

The unfortunate part of the glowplug removal is the turbocharger needs to be removed to allow glowplug removal for cylinders 3 & 4.

I would not remove injectors for compression test. It allows the high pressure fuel pump to pump uncontrolled high pressure fuel while cranking.

Odd that your warning light has not returned for 5 days worth of driving.

This link may work or might not:

https://gsi.ext.gm.com/gsi/showDoc.do?laborOpCode=&docSyskey=1830750&cellId=161747&pubObjSyskey=3763152&from=sm&pubCellSyskey=1217867

The link I have posted is for Holden Technical staff etc only.

Gary

Customer: replied 11 months ago.
Your link didnt work unfortunately. I have a workshop manual. It says to disconnect crank sensor and pull the fuel pump relay. Then test through each of the injector ports.
Try to direct the fuel into a container from the open pipe,when cranking. Sounds easier than pulling the turbo off, that looks to be in a very tight and restricted access or work space.
Customer: replied 11 months ago.
Unfortunately there is no adapter in the kit long enough to do it through the injector. So it looks like the turbo has to come off. Mission!
Customer: replied 11 months ago.
Just a thought when mensioned the vacuum pump. If that started to fail would it cause a stumble?
Expert:  Gary replied 11 months ago.

Hi Tim,

The vacuum pump is for the brake booster and some engine vacuum solenoids only.

It would not alter the engine before you noticed you had a bad brake pedal.

Or in other words, it would not cause an intermittent cylinder misfire.

I still think that your dealer has disturbed the fault when they changed the injectors.

You have said it is worse after they did that.

I'll look into injector compression adaptor now that you have mentioned that.

I'll come back to you this morning.

Gary

Expert:  Gary replied 11 months ago.

Hi Tim,

Some more info attached.

The adaptor you need is a bit harder than I thought, but hopefully some guidance from a shop owner will tell which one you need.

Myself, I would be doing an injector balance test first.

Has your Holden dealer given up on you?

Gary

Customer: replied 11 months ago.
Just finished making an adapter out of one of the old injectors. Pulled the guts out, cut the nozzel off, blanked off the return port, and silver soldered a fitting to the in port fitting to match up to the comp tester. Holden here will help me for a price of course, I just cant keep throwing money at a problem they may or may not solve.
They have spent 35 hours on it, charged me for 17 @ 121.00/hour, plus new parts for a missdiagosis which has cost me an additional 2000. Ive lost faith in them. They dont have the expertise. There lead mechanic cracked my fuel filter cansister and then charged me for it!
Customer: replied 11 months ago.
What does disconnecting the crank sensor achieve?
Expert:  Gary replied 11 months ago.

I would say the procedure says to remove one injector at a time to perform the compression test.

I still don't know why anybody would do one at a time.

So disconnecting the crank sensor is simply an additional way of preventing the engine starting.

I've seen many filter housings cracked by technicians, generally apprentices.

That's because they don't take the whole assembly out of the vehicle and mount it in a vice with the filter housing special holding tool.

Your modified injector should work as long as the tool seats and seals well in the head.

I would take note of the injector bolt torque, and the fit and cleanliness of the nozzle seat area, (injector and head).

Customer: replied 11 months ago.
I can see it starting if i unplug all the injectors as it indicates. Its a mission to get at the crank sensor plug. I could do the cam sensor easily enough if that would achieve the same result. I have a 1/2" drive torque wrench for sockets. But i am at a loss with the pipework. But understand the larger pipe nut actuallyl has a lesser torque, 20 verses 28nm on the small nut.
I will get it all going on tomorrow.
Expert:  Gary replied 11 months ago.

Cam sensor disconnected alone will not do it.

The pipe work has a torque spec, but I've done a few and never had an issue once you get the feel for how tight they need to be.

Here's a pic of the crank sensor, can you see the sensor has it's own short lead and connector, unlike the cam sensor?

Customer: replied 11 months ago.
I know all about it. I replaced it a couple of weeks ago. I had to do it by feel access through the LHS wheel arch. It was indeed a challange without a hoist!
Customer: replied 11 months ago.
I have tried something different. Before i started the car for the warm up for the compression test i unplugged the coolant temp sensor. The fans came on immediately. While the engine stayed cold the stumble was not present, as it warmed slightly there was the occaisional miss. I pulled the fan relay out, as the engine warmed the stumble started. I plugged the relay and temp sensor back in. The stumble stayed.
There is rocker noise. Clicking sometimes when the stumble comes in there is a deep air throat noise like gases are coming back up the intake. Only sometimes, and sometimes it occurrs when another eletrical service kicks in,like the fans or the a/c. Is this making any sense to you?
Customer: replied 11 months ago.
Heres another thing. The stumble is less when cold and also when idleing after fully warmed up.
Ill go ahead with the compression test now.
Customer: replied 11 months ago.
I recon the roller bearing is failing in an exhaust valve rocker.
Expert:  Gary replied 11 months ago.

Hi Tim,

I don't think you'll see a difference in compression readings with a exhaust rocker starting to fail, but we'll see.

The is a TAC (Technical Assistance Centre) techline about noises that sound like intermittent rockers, but is reprogram the injectors. It resets the fuel trimming values in the ECM to take the diesel knock away.

I've done this after replacing injectors, two programming routines to take the noise away. Different vehicle afterwards.

If it still has roller bearing rockers that haven't been replaced yet, there's a hogh chance of failure. The new bushed rockers don't have the problem.

Cam lobes fail as well, but the noise is more pronounced.

Gary

Customer: replied 11 months ago.
Completed compression test. All cylinders behave the same and are within 10psi to each other. I guess the next thing is to take off the rocker cover...
Customer: replied 11 months ago.
Gary, im pretty sure i have found it,there is scroring on the exhaust valve cam lobe of number 3,when I pulled number 3 injector there was soot build up on the injector nozzle as well. At the time i thought they may not have changed it...the roller is well scored as well and may have some flat spots hense intermittant. Very hard to see.Recall warrenty? Let me know your thoughts.
Expert:  Gary replied 11 months ago.

Hi Tim,

Does the NO 3 exhaust cam lobe look any different to the other cam lobes?

Can you take a photo for me?

The valves may not seat well when closed if the wheel is skidding (starting to flatspot), the lash adjuster takes up the clearance then the wheel rolls on the next cycle and the valves stay unseated.

Instead of zero lash, we have exhaust valves 2 thou of their seats. Commonly referred to as "riding valves".

Same phenomenon as solid lash set too tight.

All injectors get sooty, to different extents and nothing to go by really.

Diesels these days have 5 injections per 4 stroke cycle not 1 of years ago.

2 pre, 1 pre-main, 1 main, 1 post-main or something like that.

The programmers have a lot to get right.

Gary

Customer: replied 11 months ago.
I have closed the shed for the night but will have a closer look at the cam tomorrow. I will say this, the roller and cam lobe have a scored surface not shiny like the other seven.
Expert:  Gary replied 11 months ago.

You're onto it now Tim.

It is a job to replace a camshaft and rocker arms.

Looking forward to photos.

I would take some pics for your records against Holden if you need to.

Gary

Customer: replied 11 months ago.
I cant get the photo to send. I can add the file and load it but nothing happens when i hit send.Does it need compression.
Expert:  Gary replied 11 months ago.

I'd say the file is too big.

Are you going to price up a cam and rockers etc?

Gary

Customer: replied 11 months ago.
Holden will be in a hold world of hurt if it turn out I have needle rollers installed as opposed to the bushes you mensioned.Have you an email I can send the photos (2)
Expert:  Gary replied 11 months ago.

Yes Tim,

Send your pics to:

***@******.***

It sounds by your description that a roller has started to skid then a flat spot develops, then the roller and cam lobe wear at rapid rate.

Gary

Expert:  Gary replied 11 months ago.

Hi Tim,

I've seen your pics.

Now that you have seen an obvious issue, I would check your history with Holden, and we'll then see what is the next step.

Parts alone for the top is about $1500 from memory.

Gary

Customer: replied 11 months ago.
Gary, Holden finally got back to me. They said that the rocker work was done for a previous owner. But they are not sure what parts were changed. Because of that they said they are going to do the repair under warrenty anyway just to be sure. What a crock! Are you still with Holden in Brisbane?
Expert:  Gary replied 11 months ago.

Hi Tim,

I'm not working F/T for Holden at the moment.

I'm looking at another foreman role for Holden within Brisbane.

That's good they are coming to the party for the cam and rockers, hopefully it runs smooth after they do the job.

They may have replaced parts before the revised rockers cam out, bushed wheels versus needle rollers.

Gary