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Old Sep 20, 2006 | 06:54 PM
  #1  
IVRedZ28LS1's Avatar
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I have a 98 Z28 it has cam and heads on it. I installed a Harlan shift lite on it and set it up for 6500 RPM for it to come on. My Rev Limiter is set at 6800 RPM and my car is fully tuned. On the street or the Track my shift lite never comes on. I hit the rev limiter like about 4-5 times then the lite comes on. I have The SHIFT LITE set right now for 6200RPM. AND IT SEEMS TO WORK okay. BUT I was told that the tach is slow to respond and it can be off at times. That the reason I installed the Shift lite so that it can tell me when to shift tothe next gear. I wired up the Shift light to the white wire (TaCH SIGNAL) close to the PCM. What could be causing this? HAS ANYONE RUN INTO THIS PROBLEM BEFORE? IS THERE ANYWHERE ELSE I CAN WIRE UP MY SHIFT LIGHT SO THAT IT CAN BE ACCURATE FOR IT TO WORK CORRECTLY? THANKS GUYS.
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Old Sep 20, 2006 | 07:06 PM
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The tach signal from the PCM is not slow. The part that is slow is the mechanical tach needle on the dash, not the signal that feeds it. The signal on the white wire is accurate, keep using it.
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Old Sep 21, 2006 | 05:32 PM
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Okay I have my shift light wired at the Pcm (white Wire). My harlan shift light is is set up right now at 6200rpm where the light comes on. But my Revlimiter is set at 6800RPM. I talked to my tuner which uses HP TUNING SOFTWARE. IT IS SET UP AT 6800RPM. But for some reason my shift light set up right now and comes on at 6200rpm in every gear and park idling. IT WILL NOT COME IF I SET MY SHIFT LIGHT AT 6500rpm driving my car or idling. I will hit the RevLIMITER a couple of times before the light comes or never comes on.WHAT CAN IT BE? CAN SOMONE HELP ME PLEASE? THANKS FOR THE HELP Brad8266.
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Old Sep 22, 2006 | 05:12 PM
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Can someone help please? Has anyone ran into this problem before? What did you do to fix this? Thanks for your advice guys.
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Old Sep 22, 2006 | 05:23 PM
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Have you tried setting your shift light to a lower RMP such as 3200 and running a scan with HPT to see what RPM it is actually coming on at?
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Old Sep 24, 2006 | 01:42 PM
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I have not tried this at all. Thanks I will try it out and see at what RPM shift lite is coming on when set to 3200rpm. Thanks. I will let you now what happens.
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