ls6 wont start - sensors?
#1
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so, i've got the ls6 from a 2002 zo6 in a 99 tahoe. the engine fires and runs for a few seconds then stops. i belive its a safety mechanism. possible some senor that it is looking for. so the question is what senors are a must to have hooked up in order for this to run? or is there something else im missing?
thanks
thanks
#4
TECH Junkie
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Did it run, previously?
If these are the first attempts to start it, after the swap, then I agree with the person above^.
If the 2002 VATS works similar to a 98/99, then I'll guess that the BCM was not carried forward to your Tahoe.
The BCM puts out a 30 or 50 cycle signal, which is detected by the ECM. Once this happens, the ECM allows fuel pulses to the injectors.
If this is the trouble, you can have the VATS function deleted from the ECM.
If these are the first attempts to start it, after the swap, then I agree with the person above^.
If the 2002 VATS works similar to a 98/99, then I'll guess that the BCM was not carried forward to your Tahoe.
The BCM puts out a 30 or 50 cycle signal, which is detected by the ECM. Once this happens, the ECM allows fuel pulses to the injectors.
If this is the trouble, you can have the VATS function deleted from the ECM.
#5
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Does sound like the VATS. However, regarding sensors, do you have the MAF hooked up?
Jon
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Jon
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#6
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The junkyard I bought it from showed that it was running in the car before they pulled it and sent it to me. The 99 tahoe was the last year of that model, so the security might be old tech. It does have the resistor key but I can tune the ecu if I reprogram it anyway, just want to make sure that it is the prob.
As for sensors. I have the maf and O2 and the fuel pressure sensor hooked up.
As for sensors. I have the maf and O2 and the fuel pressure sensor hooked up.
#7
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I'd agree, sounds like VATS to me!
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#8
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ok, I got OBDII working and here are the codes:
P0452 - Evap Pressure Sensor / Low Input
P0453 - Evap Pressure Sensor / High
P1125 - Acc Pedal Pos System
P1516 - Command Vs Actual TP Perf (TAC Mod)
P1518 - PCM To TAC Mod Serial Data Circuit
P1639 - 5 volt Ref 2 circuit
The pedal is attached and working the throttle body so I'm not sure why that's there. I'm thinking I got the Fuel Pressure Switch connected wrong. But these codes aren't showing the VATS code that I have seen others saying is there when scanned?
P0452 - Evap Pressure Sensor / Low Input
P0453 - Evap Pressure Sensor / High
P1125 - Acc Pedal Pos System
P1516 - Command Vs Actual TP Perf (TAC Mod)
P1518 - PCM To TAC Mod Serial Data Circuit
P1639 - 5 volt Ref 2 circuit
The pedal is attached and working the throttle body so I'm not sure why that's there. I'm thinking I got the Fuel Pressure Switch connected wrong. But these codes aren't showing the VATS code that I have seen others saying is there when scanned?
#9
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Alright, I had the FTP sensor on the wrong wire. But now that I fixed that and reset the error codes, I'm left with only these two:
P1639 - 5 volt Ref 2 circuit
but this one doesn't make sense because it was in there twice and know it's only in there once:
P0452 - Evap Pressure Sensor / Low Input
So, I guess the 5 volt ref 2 circuit is the problem. I'm not sure where the wire goes. I can't find a 5 volt to connect it to???
P1639 - 5 volt Ref 2 circuit
but this one doesn't make sense because it was in there twice and know it's only in there once:
P0452 - Evap Pressure Sensor / Low Input
So, I guess the 5 volt ref 2 circuit is the problem. I'm not sure where the wire goes. I can't find a 5 volt to connect it to???