Natural gas

Assuming a late model EFI motor. How would the system respond to enrichment of the intake air with natural gas? LNG, CNG.

What % would be OK?

You can convert a car to run on natural gas, but I don’t think adding it to the intake air is the way to go.

Agree - not something you want to add in to a regular engine, have to convert.

LNG is LIQUIFIED NATURAL GAS! It comes from overseas in large tankers that are built like giant thermos bottles. When they land in the US the LNG is GASIFIED by a shore-based facility and put into the pipeline distribution system.

The gas that heats your house or powers your car (as CNG, COMPRESSED NATURAL GASS) may have started out as LNG, or normal US produced gas from a local well. You cannot put LNG into an engine; the heat required to vaporize it will create a giant iceball under your hood.

You may be confused with LPG or LIQUIFIED PETROLEUM GAS, usually propane or butane. This is the stuff that goes into your barbecue.

In any case, if you want your car to run on either propane or natural gas, thast acn be done. But you can’t mix it with gasoline in the engine, as stated by others.

To answer your question, injecting extra fuel (of any sort) into the air intake will very much confuse the ECM (the computer that controls the engine) and I would imagine would quickly make the CEL come on.

MAYBE, on SOME cars, at a steady state cruising speed, a small amount could be injected and the computer would compensate by reducing the amount of gasoline being injected…But its a very narrow window that the computer can compensate for. Accurately injecting the extra gas so as not to exceed the computers ability to compensate would be very difficult…Trying to save money? Not very likely unless you can get the other fuel for free…