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References to systems which are not approved to be installed in the United States have been removed from this thread
http://cngchat.com/index.php?pid=9#furtheringillegal
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Has anyone done any adjustments on these systems for a 6 cyclinder 4.2l or close?
the problem I have is that the CNG works just fine at idle and low end just fine. It seems to bog down and go only to 3500RPM, not to talk about the fact that it is simply gutless. I can entualy get it to speed like 40MPH or 60MPH on the highway. After a fre minutes I get Loss of Power error on GM Envoy and it idles only, no more throutle available till I shutdown the vehicle and restart it on reg gas.
I can't seem to be able to start the vehicle when warmed up on CNG either. I can however change over once started on reg gas. The problem I have is that even the timing advance kicks (I hear the click on the relay for timing advance) when I touch the gas pedal, it seems like it is not advanced enough. I though with CNG the timing needs to be set to 12.
Any ideas?
Thanks,
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