Excessive gas consumption 94 Tbird 4.6litre V8

Recently acquired a 94 Tbird 4.6L V8. Changed one fuel injector and fuel regulator. White smoke is present with smell of gas and terrible gas use. Have used 2 bottles of injector cleaner. Also idles rough at low rpm’s. Inexperienced mechanic at best. RSVP Lee

Why did you change ONE fuel injector and fuel regulator? Have you checked your coolant level? What is your specific “gas use?”

You might want to check the coolant temp sensor for the computer. If this has failed where it’s telling the computer the coolant temp is at -20? and it’s not, it’ll dump gas faster into the engine faster than it can burn it and you get gas vapors out the pipe.


A mechanic checked out the engine and the result was #6 cyl bad on fuel injector. I changed the fuel regulator from advice from another mechanic. Coolant level is ok. Gas use is about 4 mi to the gal. Thanks for the help, Lee

Exactly how do I check the coolant temp sensor? Thanks, Lee

Autozone has a repair guide and component locations for the 94 T-Bird. You will probably have to register and enter your vehicle make, model, year, and engine.


Ed B.

I did register with Autozone, but seems too elementary to address the excessive gas consumption. I’m stumped, what would cause the engine to use gas to the rate of 4 miles to the gallon? Thanks, Lee

How many miles on this car?? Is the CEL on? Does the CEL even work?

Rough idle, bad fuel mileage, strong gas smell, and white smoke could all point to an intake manifold gasket leak where coolant is entering the combustion chamber, or chambers all depending.
And it doesn’t take much coolant to do this either.

It would be interesting to hear how the No. 6 cylinder fuel injector was diagnosed. If the car were mine I’d have to connect a vacuum gauge to it as a first step to make sure everything mechanically is on the up and up.

It sounds as if an injector is being held open (firing constantly) This condition may cause the engine to hydrolock and bend rods and valves!!! Using a noid light or DVOM test all injectors for a pulse command from the computer. If the reading shows a constant ground, it is most likely a wire in the harness grounding on the engine. 4MPG and still running is impressive, and most likely not a bad CTS unless it is very cold where you live.

I’m, in Anchorage Alaska, kinda cold here. What kind of pulse command in terms of voltage should I look for? What is a CEL? The #6 cyl was compression checked when diagnosed. ?Thanks, Lee