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Welding / Disconnect Brain?

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Old Sep 17, 2008 | 06:16 PM
  #16  
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Paul Dortkamp
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Thanks for the advice Craig, with the LHS coil disconnected it stays rough, RHS disconnected the engine does not fire. So it looks like a coil or wiring issue on the LHS. A better prognosis than fried brains.
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Old Sep 17, 2008 | 08:57 PM
  #17  
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Could just as easily be injectors on that bank - check the status of the Ignition Protection Relay - next to the brains (any LED's on while running?) Any wiring issues on that bank?

Check for spark next on that bank - will tell you which it is.

no spark -> no injector (EZK is the master over LH)

No injector you probably still do have spark...

Alan
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Old Sep 18, 2008 | 02:56 AM
  #18  
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Hi Alan, thanks for the assistance. i have checked the Ignition Protection Relay next to the brains no LED's were on on while running. I can not see any wiring issues but not really sure what to look or listen for.

I checked for spark at the LHS coil with another lead held near an earth, I did not see any spark from the coil. Does that point to the EZK unit? Should I try and swap the coils? How do I check for no injector?
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Old Sep 18, 2008 | 03:06 AM
  #19  
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Originally Posted by Paul Dortkamp
Hi Alan, thanks for the assistance. i have checked the Ignition Protection Relay next to the brains no LED's were on on while running. I can not see any wiring issues but not really sure what to look or listen for.

I checked for spark at the LHS coil with another lead held near an earth, I did not see any spark from the coil. Does that point to the EZK unit? Should I try and swap the coils? How do I check for no injector?
Check for spark with a spark plug grounded to the chassis with a booster cable. DO NOT HOLD IT! - the 928 ignition circuit has enough power to get you a Darwin Award - postumously!

To check injectors get a Noid light Or an injector listening probe tool. If you pull a spark plug after you cranked smell it for gas fumes....

Alan
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Old Sep 18, 2008 | 04:09 AM
  #20  
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Hi Alan, thanks for the help. I found the gremlin, it was the connection to one of the "ignition switch units" up the front, near the light bar. The LHS plug was loose in the socket. I pushed it home, "click" and all is well. Thanks for helping to narrow down the search area.
After a tip from one of the local specialists, I was going to swap the connections to see if one of the units had failed, but did not even get that far. I can now go and fetch the track car for a practice day on Friday.
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Old Sep 18, 2008 | 09:57 AM
  #21  
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Yes those ignition final drive stages were the next focus area - then coils themselves & distributor...

Alan
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Old Sep 18, 2008 | 10:49 AM
  #22  
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That was going to be myh prognosis, the ignition units up front ... I had the exact same symptoms on one of mine, that was the issue.
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