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x-90 P0335 code
When i hooked to small wires that were back probed to the computer i noticed interference on the wave form. Like a pulsation or bubble riding along.  This led me to believe you were right about the grounding issue of the sheathing to avoid interference.   So all these measurements sure taken before fixing G103 ground.

the next few post will show the bubble or interference move through the wave form. 

The option left is to insert my own ground wire with a filter capacitor in tow to make sure everything is clean. Then i can see if the same piggy back bubble is on the waveform again.  Once the signal is clean the only other option would be to replace the computer. I have included the signal from the Cam sensor or CMP sensor as well.  It shows a perfect square form with around 6 volts signal.  i wanted to include this for your own information as well.

that wave form post 62
what is the volts/ per graduation. 1v? (we see devisions Peak to peak)
that wiggle is the teeth on the crank cog. and will look like that.
it will rise fast and peak the voltage then when the tooth ends, the signal dies away at the rate of the stray capacitance in that wire run. then repeats.
the sensor is in effect a spike generator, pure magnetic.
unlike any hall sensor made.
the hall makes pure square waves. as you saw with CMP there.
the crank sensor makes fast pulses.

is the vertical knob at 1v./dev and is that 10x probe.
with the knob VERT not moved
use 1.5v, AA or AAA battery and measure (dial set to DC verT) and see if it moves 1.5 divisions. if yes that those are 1devisions, if it goes off the scale, then 0.1v/divisions.
Id have to see then knob setting VERT
and all words on the probe, or some have x1/x10 lever on the probe.
is the brightness that bright or just camera messing up as all do.?
yes with the CMP i had it at 1v/div and the brightness was that bright. i had adjusted the focus prior to the reading but never did while getting the wave form.

so setting with CKP was 1v/div on 10x probe

when i show the CMP its 2v/div on 10x probe
I have included a youtube video of the wave forms so you can see them visually and not a still or them.

(05-28-2019, 04:21 AM)CSUSBgeochem1 Wrote: I have included a youtube video of the wave forms so you can see them visually and not a still or them.


real nice video.
all that is good,  you have 4v Peak to peak. CKP signals, that plenty
so must be going low driving, 1 in 20 pulse drop out , will set 335 error.
i call bad wiring, 
i  would run new cable, 2conductor shielded.
for CKP, for sure cheaper than spare ECU, would be.

i can see that scope has ground 0v in center of screen and you get 2 volts above zero then -2v below, and the ECU has zero crossing detector for CKP input.
so that is a good signal for idle .

if CMP drops out driving the car bucks hard or dies for length of loss of CMP.  all spark ends at the lost of CMP, no matter how fast the loss. (will be felt as misfire or bucking)

my guess when car is moving the CKP drops out due to wire failing.  (one thing to know is that the signal my pass through (IDK) huge injector plug-in in the harness just below
the intake manifold,  if yes, then reseat it.

this connector is well hidden above Alternator and below intake manifold.

if CMP is good, then the engine will run fine.  just like 1992 to 1995 did with NO CKP there those years.
what will fail is , no misfire detection. mostly.

nice work you did !!!!!!!!

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