installed new prom now my timing advances 8 degrees when i hook up the tan wire?
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installed new prom now my timing advances 8 degrees when i hook up the tan wire?
i just installed a hypertech street perfomer prom chip and went to set my timing. i set it to 5 degrees like im supposed to but whenever i connect the tan and black wire it automatically jumps up to 12 degrees. anyone have any idea why. im wondering if my cts has anything to do with it?
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
Because the timing is now under ECM control.
Not DIY_PROM, moving...
RBob.
Not DIY_PROM, moving...
RBob.
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From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
garbage in garbage out
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Car: 90 IROC
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Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
I don't think that's abnormal. It's why you disconnect the wire when you set the timing. When the wire is connected, the ECM controls the timing and it would vary depending upon many factors. The only way to reliably set it is to disconnect the ECM and set a base timing that it will never go below. When you plug it back in, the timing advances to keep the engine cooler and produce better manifold vacuum (amongst other things)
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From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
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Axle/Gears: 3:42
Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
i just installed a hypertech street perfomer prom chip and went to set my timing. i set it to 5 degrees like im supposed to but whenever i connect the tan and black wire it automatically jumps up to 12 degrees. anyone have any idea why. im wondering if my cts has anything to do with it?
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iTrader: (2)
Joined: May 2009
Posts: 3,371
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From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
Make sure you disconnected the est wire. It is dark brown w/black stripe over by the strut tower on passenger side.
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From: Tampa, FL
Car: 1987 Firebird Formula 350
Engine: 5.7 Vin 8 L98
Transmission: R-700 Auto
Axle/Gears: factory
Re: installed new prom now my timing advances 8 degrees when i hook up the tan wire?
I have a 1987 Formula 350 and it took awhile for me to actually find the EST wire. It was hidden from view behind the large plastic wiring harness cover. Attached is a picture of the wire and location on the passenger side firewall.
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