1993 Z28 Starting Troubles!
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Joined: Mar 2020
Posts: 1
From: Oklahoma
1993 Z28 Starting Troubles!
I just recently bought a 1993 Z28 LT1. Drove it home over an hour away and ran like a champ. Drove it for 2 days before it started to drive funny. Didn’t seem like it was getting full power, and occasionally it would act like it wanted to die. Now it won’t start at all, rather just continuously turn over. Checked a spark plug and it’s not getting and spark to it. Checked the connector from the ignition coil to the Optispark and it’s not getting any spark. Replaced the Coil and ICM and still no spark. NEED HELP PLEASE AND THANKS IN ADVANCE!
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Joined: Nov 1998
Posts: 71,086
From: Hell was full so they sent me to NJ
Re: 1993 Z28 Starting Troubles!
Did you scan the ECM for codes:
http://shbox.com/1/dlc2.jpg
http://shbox.com/1/Dtcs.htm
With no spark, the cam position sensor in the Opti can be the problem. There are codes for loss of signal from the Opti. The “fatal” code (DTC 16) does not turn on the SES light. Here's a test procedure to verify the signals are reaching the ECM, and the ECM is using the data to fire the coil:
4th Gen LT1 F-body Tech Articles
As. a quick check, when the starter is cranking the engine, does the tach move up 200-300 RPM?
http://shbox.com/1/dlc2.jpg
http://shbox.com/1/Dtcs.htm
With no spark, the cam position sensor in the Opti can be the problem. There are codes for loss of signal from the Opti. The “fatal” code (DTC 16) does not turn on the SES light. Here's a test procedure to verify the signals are reaching the ECM, and the ECM is using the data to fire the coil:
4th Gen LT1 F-body Tech Articles
As. a quick check, when the starter is cranking the engine, does the tach move up 200-300 RPM?