Zafira A z18xe misfire

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faraday
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Zafira A z18xe misfire

Post by faraday »

Car Data:
Opel Zafira A 2002y engine code Z18XE.

Car runs perfect at IDLE and drives smooth with rev up to 3000rpm, above 3000rpm after few seconds checkengine lit and fault code missfire on cylinder 1 and 4.

4 garages could not fix issue. Fitted new plugs, dis , even brand new ECU.

Diagnostic does not show any problem (except DTCs), all parameters in measuring blocks seemed ok.

First osciloscope measurement reviled problem. CKP waveform not ok.
Attachments
x18xe_CKP.jpg
koronka.jpg

liviu2004
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Re: Zafira A z18xe misfire

Post by liviu2004 »

Well done, how was the damage done? Dis must be genuine, aftermarket miss ballast resistor, will throw ecu p1600 + p1606.

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VASTech
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Re: Zafira A z18xe misfire

Post by VASTech »

Good job! Must be great satisfaction when you get done one like this! Well done!

faraday
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Re: Zafira A z18xe misfire

Post by faraday »

liviu2004 wrote:
Sun Dec 20, 2020 4:33 am
Well done, how was the damage done? Dis must be genuine, aftermarket miss ballast resistor, will throw ecu p1600 + p1606.
Unfortunately I don't know full history of this car. Customer said the cylinder head had been refurbished.
Picture from reluctor ring was made by mechanic after disassembly.

faraday
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Re: Zafira A z18xe misfire

Post by faraday »

Made some additional measurement and I think it is obvious why ECU interpret this as misfire on higher RPM. Look at signal amplitude at low and high rev and how clear it looks with math channel (RED).
Attachments
4000rpm.jpg
1000rpm.jpg

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Frank0705
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Re: Zafira A z18xe misfire

Post by Frank0705 »

Nice Diagnose! Including a math channel gives a clear image why the ECU is seeing a misfire. What made you start with a measurement of the CKP? Was it a DTC or something else that made you check this signal first?

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Fat Freddy
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Re: Zafira A z18xe misfire

Post by Fat Freddy »

Is this repaired?

Went down this road about nine years ago with same engine. https://www.autonerdz.com/cgi/yabb2/YaB ... 33103032/0
I repaired the damage but still had a problem that only disappeared with another (the 3rd) ecu, since then I've been unsure how many faults I was dealing with. One of those jobs that wouldn't go away.

So interested if once you rectified the problem and it was straight out the door.

Thanks

faraday
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Re: Zafira A z18xe misfire

Post by faraday »

Fat Freddy wrote:
Fri Jan 01, 2021 9:46 am
Is this repaired?

Went down this road about nine years ago with same engine. https://www.autonerdz.com/cgi/yabb2/YaB ... 33103032/0
I repaired the damage but still had a problem that only disappeared with another (the 3rd) ecu, since then I've been unsure how many faults I was dealing with. One of those jobs that wouldn't go away.

So interested if once you rectified the problem and it was straight out the door.

Thanks
Yes, it was straight out the door.

faraday
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Re: Zafira A z18xe misfire

Post by faraday »

Frank0705 wrote:
Fri Dec 25, 2020 5:45 pm
Nice Diagnose! Including a math channel gives a clear image why the ECU is seeing a misfire. What made you start with a measurement of the CKP? Was it a DTC or something else that made you check this signal first?
The only dtc's was from misfire. During diagnosis I did not spot any problem I mean engine operate smooth on idle and higher rpm, when DTC was set engine still operated ok and after ~10s starts to stall (engine cuts injectors). The other garage changed DIS, sparkplugs, ECU so I assumed it has to be related with sensor.

jueja
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Re: Zafira A z18xe misfire

Post by jueja »

I once encountered the same issue on the same engine. The engine had been swapped and in this process the carter was taken off, letting it slightly rest on the crankshaft sprocket bending a tooth. The deviation in the signal was obvious well below 3000 rpm, nevertheless only then the pcm would code and shut off the 2 coils.

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