Just installed my FAST and LS2 TB, and had a couple of issues. I used new injectors, and they're the same length, but a little fatter where they plug in to the manifold (Racetronic) and where you clip the retainer is slightly different. One of them leaks aroung the top O-ring where it goes into the fuel rail cup. There's two slots available for the retainer clips to lock them in, with a plastic (blue) removable ring around the lower one. I tried them in the first slot, and they appeared to not seat in the manifold, so I removed the blue plastic clip, and they seem to fit OK, but one leaks. I think I can tinker around and fix this problem, but the next one worries me.....
When I got it all together, and started the motor, it raced up as if it were floored. Obviously, with a brand new H/C setup, I shut it down immediately. Tried a couple of more times with the same result. When I installed the LS2 TB, it wouldn't fit like the stocker, so I remember reading somewhere that you just invert the thing. I got an adapter harness, and it's added length made this possible. I don't know how to stop the engine from racing, or what could be the cause. Anybody with experience or advice is welcomed. Thanks.
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'02 B/B LGM Lts, Corsa. TEA/Trickflow215s/Crane cam, Powerbond pulley. FAST 90/LS2TB. Meziere EWP. Harland Sharp roller rockers, and Vararam. Oh yeah, C6Z shifter. I need an intervention.
Sounds like somehow some of the wires are crossed. There are two throttle position sensors, one sees low voltage as throttle input, the other sees low voltage as lack of throttle. I am assuming if they are crossed, the throttle body will think the pedal is floored. This is from the service manual:
"The TP sensors are used to determine the throttle plate angle. The TP sensors provide the engine control module (ECM) with a signal voltage proportional to throttle plate movement. The TP sensor 1 signal voltage at closed throttle is above 4 volts and decreases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is below 1 volt and increases as the throttle plate is opened. "
I have been comparing the pinouts from the LS2 to the LS6
On the LS2:
Pin Wire Color Circuit No. Function
A BN 582 TAC Motor Control - 2
B YE 581 TAC Motor Control - 1
C TN/WH 1704 Low Reference
D D-GN 485 TP Sensor 1 Signal
E L-BU/BK 1688 5-Volt Reference 2
F PU 486 TP Sensor 2 Signal
LS6
Throttle Actuator Control
A YEL 581 TAC Motor control - 1
B BRN 582 TAC Motor control - 2
Throttle Position Sensor
A DK GRN 485 5 Volt Reference
B PPL 486 Low Reference
C DK BLU 417 TP Sensor 1 Signal
D YEL/BLK 487 5 Volt Reference
E WHT 484 Low Reference
F PNK 427 TP Sensor 2 Signal
Can someone explain to me why my power steering pump is in the way of the LS2 throttle body? Putting on the FAST 90 right now...
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2003 Z06 - 1.473 sixty foot , 383 Stroker NA, AFR 225's, Fast, Vararam, LG Longs, 390 Gear, thru stock mufflers. Pete Incaudo Street Cam, Full interior, stock suspension. All out of the box parts, no porting or tricks. 10.66 @ 129mph
I got it apart, and it's not running yet, but I found a dumbass thing I forgot. When I unplugged the fuel line, prior to removing the rail, I had a plastic cap to keep the gas from leaking all over the place, Well..... yup, I forgot to remove the thing. Consequently, the fuel rail intake was plugged. OK, this explains gas shooting all over the place, but why in the world would the car even run with no gas, at WOT, no less?
Also, Headhunter, thanks, but I got a complete wiring harness adapter, and there's only one way to plug it in.
I got everything back together and found the plug in one piece, decided to change back to the stock injectors, because the Racetronics weren't seating that well into the manifold recesses. Now it won't start. Checked fuses and didn't see anything obvious, and of course, all plugs. Could I have F-ed up a sensor, or maybe jammed a switch/relay/ valve? For instance, what does this valve? do?
Got it back to running, only w/o the FAST/LS2 combo. The starting issue was due to tripping the anti-theft interlock, and as soon as that was cleared, it started right up. Still revs as if it's getting partial throttle, even with the old injectors instead of the Racetronics. Oh well. Back to the LS6 manifold for now.
I feel your pain bro. I'm having some issues with my install also. I think the Fast 90 is the culprit. Good Luck.
Are you using the FAST TB? I've heard these can stick. Mine is a stock (new) LS2 with an adapter harness that's plug-n-play (supposedly) with the LS6 harness. I've checked the throttle blade position and it is fully closed, yet the thing revs up, although less than at first.
Are you using the FAST TB? I've heard these can stick. Mine is a stock (new) LS2 with an adapter harness that's plug-n-play (supposedly) with the LS6 harness. I've checked the throttle blade position and it is fully closed, yet the thing revs up, although less than at first.
No, I have a Nick Williams TB. My car actually idles pretty well it's just that I believe I have a vacuum leak somehwere. My long term fuel trims are pegged at +25 and my short term fuel trims are in the +40's. Also, when I go wot my 02's show very lean and behave erraticly. My ve table can't be that far off and increasing it has no effect. Has your car been tuned at all? The Fast 90/90 set-up adds a whole new dimension to tuning so I've been told. Your RAF tables will need to be changed as well as your adaptive idle measurements. I hope you get your problems figured out, I'm looking for a smoke machine (thanks speedratchet ) bright and early tomorrow. Hopefully I can find the leak!
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) bright and early tomorrow. Hopefully I can find the leak!
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