Intermittent DNS
 

So I now have the intermittent DNS (dreaded no start) on my 91 Z. I want to try to bypass the clutch safety switch to see if that helps. Can I just unplug it and jumper across the plug or is there more to it?

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Re: Intermittent DNS
 

Is it DNS when hot only? If so.. starter contacts


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Re: Intermittent DNS
 

Verify that both battery terminals are clean and tight. Disconnect any after market systems attached to the battery terminals.

Put the ignition key to ON, Engine not started. Note the battery voltage on the instrument panel. Turn the key to start, while watching the battery voltage meter. If the needle does not deflect, then investigate the starting circuit, ie clutch switch, VATS, TDS.

If the volt meter does deflect, it means that the starter solenoid is energizing but the solenoid contacts are not passing current to the starter motor. Rebuild the starter solenoid or replace the starter.

NOTE, keep this procedure handy because it has to be done when the car won't crank. For an intermittent problem like you stated, you will have to wait until the next failure.

Good luck,

Jim

Re: Intermittent DNS
 

Yes so far its only when hot and not every time. Thanks for the advice. Hoping I don't have to pull the plenum again.

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Re: Intermittent DNS
 

EXACTLY the same symptoms I had when the starter solenoid contacts were dirty.

Re: Intermittent DNS
 

OK, so it happened again. I watched the volt meter and the needle didn't move when I turned the key to start. I was able to get a push start. What's the next step?

Re: Intermittent DNS
 

TDS is the theft deterrent system, the resistance chip in the ignition key that is checked to allow the computer to allow the starter circuit to energize.


The next step is to rebuild the starter solenoid or replace the starter.


Jim

Re: Intermittent DNS
 

OK now I'm confused LOL. In your first post you said if the needle did t move it wasn't the starter but to into the clutch safety switch or VATS? Sorry but I'm a dummy when it comes to diagnosing electrical issues.

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Re: Intermittent DNS
 

If it is Hot start only, it is the contacts of the solenoid. I chnaged the wiring a bit to minimize the solenoid electrical path, I still ended up pulling the starter and replacing the contacts.. The Challenge is diagnosing while hot..

But because it is only when hot, the contacts make more sense than the clutch switch

Re: Intermittent DNS
 

OK thanks

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