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If it Walks Like a Duck, Talks Like a Duck,
Posted to Technical Discussion Forum on 6/11/2013 10 Replies

it must be a chicken!

Had a Intrepid towed in for a no-start. One of my techs had a look at it. He said that it sounded like it was out of time and thought he'd try this technique that he read about. The technique is scoping cam and crank and see if they are in sync.

Here is the capture he showed me of the crank and cam during cranking.

Looking at known good captures, this capture is in sync. Cranking the engine, it will kick back and backfire out of the intake periodically. Definately sounds like its out of time although the cam/crank says otherwise.

I thought it would be prudent to take a capture of in-cylinder while we're cranking. Here is the capture of cam/crank with #1 in-cylinder. Little different result eh?

It looks like it jumped time, but jumped to a spot that the crank and cam pulses lined back up! I thought I'd share this as it was pretty neat.

For those that use Pico, here is the scope capture in psd format.


Harvey from British Columbia

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car Vehicle Data

1997 Dodge Intrepid 3.5L

Engine3.5 L
Trans4-speed Automatic (Electronic)