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what is the time base set to ? horz, , I want to know the PRT, pulse repetition time. CKP.
due to the blooming of the trace (camera) I can not see if the blooming in a high frequency component there, as in NOISE.
if the blooming is real then set the input to AC mode and shorten the (higher freq) the horz. knob. dial faster sweep speed, see if there is some noise there.
also race the engine rpm so i can see the PRT go shorter.(time) and see if the 4v-p--p rises.
http://www.fixkick.com
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I have gotten on a lot of what you suggested ahead of time. I figured if i ran new cable it would clean up the signal and nothing is left but i think i figured out the problem either way. There is a mad shimmy at the crank im surprised i didnt see and i need to make sure the cog is still tight.
if so then the crank has some shimmy internally and the short block is compromised. I will submit all pictures and info in further posts.
The horizontal was set to 2ms/div to display the one FULL waveform zoomed in. That was the setting showing the wiggle on the signal in the previous video.
I ran new shielded wire from the CKP to the computer and its signal is even better than in the video posted. 18 gauge foil shielded WITH a ground wire.
At the CKP i left all the wire on the plug and added alumifoil tape to shield it. I extended the ground wire on the purchased cable and wrapped some wire around the rest of the wire after the alumifoil tape. Its hard to describe and i forgot to get pictures. but the final picture shows how thick the line is now to the sensor. Alumifoil tape doesnt bend very easy.
The signal was great at the computer after all this work but the code was still triggered. This is why im leaning on the crank vibration more than the computer. I need to figure out why there is a harmonic vibration going on.
I will post the video of me obtaining the signal after all the work as well as reving the motor to show the outcome on the oscilloscope.
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please feel free to use any info, video and pictures on your website. i release liability and copyright to you as you are the key source for this information.
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Well it looks like the harmonic balancer wasnt the issue. I purchased a new one from Low Range Offroad because they were reasonably priced. Seems like it reduced the vibration slightly but there still is a slight vibration, and i checked the motor on my sidekick and i dont see anything similar. Makes me wonder if the crank snout is bent in some way. But i doubt this little vibration is whats throwing the code.
The signal is getting to the computer through the newly ran wire and the signal is clean. The only thing left is the computer but im afraid to touch it. Its going to be hard to find a 2wd manual computer for this x-90. Ill check to see if any of the caps have swelled. but still have the code
