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Discussion Starter #1
This morning on the way into work I noticed the J&S was showing deto... the odd thing is my AFR was 12.5:1 and I was NOT in the throttle slowing down for a red light.. and I had been slowing down for several seconds.

Sitting at the light the J&S STILL was showing deto... so I babied it the last 1/2 mile to work.

I get into the parking lot, turn the car off, then turn the key on... the J&S gauge goes through its little light self check... and it stops 1 light short of finishing.

I have no idea why it wont go through its full self check... but I know I'm NOT getting deto with the engine off.

Anyone know why it wont finish the self test and it stops on the next to last light on the left???

BTW... the J&S is hrad wired into the wiring harness so I doubt it'll be a loose wire there.

Thanks to all that reply!!!

John
 

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well, you either are experiencing detonation (unlikely), you have a bad J&S unit, the wiring has developed an abnormal condition (short, high resistance), or your knock sensor is going bad. I don't know how you have it hardwired in (solder, quick splices, etc.) but you still may want to check to make sure the connection is good. aside from that, a knock sensor is $38 wholesale, so it seems to me the least expensive thing to try. you may indeed have a bad J&S unit, but I'm sure that's on the expensive side
 

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Discussion Starter #3
I "think" it was the cord that goes from the unit to the gauge, I jiggled it a couple of times and everything started working right.
 

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Hey 03OrangeSVT, Im planning on getting the J&S unit. How difficult is it to install and will this unit act as an added insurance to my current tune? Im also curriuos about the adjustment this unit will make when upping the boost a couple of pounds.
 

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Discussion Starter #5
Installing it really isnt hard at all, just a couple of wires and then your done. The hardest thing is getting the right wires... you tap into them right at the ECU.

I trust my J&S completly... I've even turned off the knock sensor in the ECU and I soley rely on the J&S.
 

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Thanks for the info, I have a couple of more questions if you dont mind.
Does this unit come with a deto guage? also, does the SVTF have a knock sensor? I wasnt aware of that. Thanks for your help and input.
 

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Discussion Starter #7
The unit does NOT come with the gauge BUT you can get one for a few bucks more, and yes the SVT has a factory knock sensor.
 
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