Looking for some insight into What I am seeing.

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hexibot43
TwoWaves
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Posts: 123
Joined: Tue May 10, 2011 5:27 pm
Location: Redwood City, Californa, USA

Looking for some insight into What I am seeing.

Post by hexibot43 »

Hello All,
We had a 2000 Buick Park Avenue, 3.8l v6 Automatic, in yesterday that was giving me some problems. I was getting a code p0303, and when I went to look at misfire history Cylinder #3 had a count over 20,000. I took a test drive, and confirmed that yes the misfire was showing up mostly on Cylinder 3 of the Misfire data. Customer had already had a go at the problem himself. Had replaced coil, wires, plugs. In fact 2 weeks ago he asked us to install a Crank Sensor for him. Finally, He decided to let us make an attempt at diagnosing it for him.
It has a Strange Affectation in the spark pattern. I've never seen something like this occur. What would you guys do to continue diagnosis of this? I keep thinking to myself that this is not real, and I'm perhaps wasting my time. What do you think?
StrangeReadingChannelB.jpg

Right after I had taken my first look at it with the Pico, I went on a test drive. I went to hit the throttle and the vehicle fell on its face. It felt like lack of fuel. So when I got back to the shop I gave the Firstlook device a go. I've included a loaded ( Power Braking) waveform using a the Firstlook Device.
Buick_Park Avenue_2000_Petrol_20141105-0001.jpg
I'm thinking MAF or Problem in the Ignition module. I was not able to go any further. We had informed the owner of the car our thoughts and what he might be looking at money wise. He opted to stop and take the car.

Has anybody seen a pattern like the one I have of ignition?
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What is this in on Channel B.psdata
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Autonerdz
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Re: Looking for some insight into What I am seeing.

Post by Autonerdz »

I keep thinking to myself that this is not real
That would be correct.

http://www.picoauto.com/support/topic9935.html

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hexibot43
TwoWaves
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Posts: 123
Joined: Tue May 10, 2011 5:27 pm
Location: Redwood City, Californa, USA

Re: Looking for some insight into What I am seeing.

Post by hexibot43 »

Thank you AutoNerdz.

I hadn't run across this before today. My old Sun machine never seemed to exhibit anything like this. This is an old Analog Scope. I still have it and use it when working with single coil ignitions. It is like an old friend. I would never give it up. I don't have a DIS adapter for it though and so wasn't using it on this car. I rarely go to the PICO when looking at ignition since I have two scopes just for that. But I had aready had the PICO out and ready to go.

Just as the other gentleman in the article said. I bit disappointing that the artifact is created by the test equipment, but we don't live in a perfect world. I'll just have to deal with it. :?

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