Opel Astra G 1.4 Misfire Problem

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antreas26
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Posts: 9
Joined: Wed Nov 06, 2013 11:10 pm

Opel Astra G 1.4 Misfire Problem

Post by antreas26 »

Hi Guys.Opel Astra G 2003,1.4cc with Z14XE engine.Custumers complaint,the car looses power on acceleration,especially when hot and check engine light is on and some times its flashing.He left the car for further investigation.I put the scanner and a P0300 and P0304 codes were stored.I know from experiance that these coil packs on Opel fail mostly but now that i have the pico,i wanted to verify the problem.On channel A (blue)i put the No3 cylinder for reference,Primary ignition voltage and on channel B (red) primary ignition current.
Bad Coil Pack.psdata
(2.44 MiB) Downloaded 1019 times
You can see that the current of the cylinder after the blue trace,hits 20A and that cylinder is No 4.I also did something else.I put between the coil pack and the plugs the 4 cop extension leads.Between 3 and 4 cop leads i put 2 Coil on spark plug tester and adjust the gap at 20kv.Start the car and No3 cylinder was having good spark and No4 no spark.I hade to reduce the gap on No4 at about 8-10kv so i could have spark.When i revved the engine on No4 the spark disappeard.I find also this method to test the strength of the coil good also.
So i changed the coil pack with a new one and everything went fine.
New Coil pack.psdata
(2.22 MiB) Downloaded 891 times

Steve Smith
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Joined: Sun Aug 25, 2013 7:22 am

Re: Opel Astra G 1.4 Misfire Problem

Post by Steve Smith »

Hello Antreas from Steve at Pico. Thank you so much for posting this information and your other posts. Sharing information like this demonstrates the value of the scope, and along with the waveforms included, enables users to build their own personal libraries based on "real life" case studies. All the very best.....Steve

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Robski
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Re: Opel Astra G 1.4 Misfire Problem

Post by Robski »

the first hosted capture = insufficient sample
The second = close but not quite enough

antreas26
Newbie
Posts: 9
Joined: Wed Nov 06, 2013 11:10 pm

Re: Opel Astra G 1.4 Misfire Problem

Post by antreas26 »

Thanks Steve and Robski for the comments.I'm new with Pico and trying to learn most of this great tool.But can you tell my how to save a zoomed image on pico software.Because when i increase the sample rate and the timebase,so i can capture with details the poblem when it occurs zooming in,i get a big file that i can't post.To get a small file you have to decrease the sample rate,but without good details.Thanks again.

Steve Smith
Pico Staff Member
Pico Staff Member
Posts: 1581
Joined: Sun Aug 25, 2013 7:22 am

Re: Opel Astra G 1.4 Misfire Problem

Post by Steve Smith »

2014-03-25_10-24-23.jpg
Good morning Antreas and thank you for raising this interesting point. You are right that saving files with a large number of samples over slow time frames results in large file sizes and this can be a nuisance when trying to share such files.
One choice is to use the “Current Waveform Only” option when using the “Save As” feature so saving only the relevant waveform rather than the full buffer
Another choice would be to send just the screen shot (with zoom activated) to share just the relevant features of the waveform, or to use the EDIT tab in PicoScope and select “ Copy Image” or “Copy Entire Window as Image” where you can then post them into a “word doc” for example and share them here as images.
You could also contact Pico at support@picotech.com whereby we can set up a link for you to post your waveform into “Picostore”. We can then review and share the waveform from here at Pico, or you could do exactly the same with providers such as “Drop box” and post the link on here for others to download/view.
I hope this helps…….Take care……Steve

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