Gas Guzzling

[Brian_D]

Weird thing happening, My 04 runs great just passed emissions, there is a service light on, showing 02 code, replaced it, code still on. until a couple of days ago was getting decent gas mileage, changed the gas cap and air filter and battery, now its eating gas like its free.. I can literally watch the gauge move when driving to work which is about 15 miles from my house..

a little more back history, the plugs, wires, cap are all about 2 years old. the injectors have never been replaced or cleaned.

I just figured if it was those it would show signs by running bad.

Since it is still running good its kind of confusing as to what can be causing this..

Any thoughts?

Thanks all,

 

[Zane M]

You need to figure out why you still have an 02 code. Did you replace the appropriate 02? If so, start checking the wiring. Depending on what reading the ECU is getting from the 02(or lack of reading), the ECU may be prompting an overly rich mixture.

Another possibility is if this is a Vortec motor, the spider injectors may be leaking-a very common problem.

 

[zombiyjay76]

Have you checked fuel pressure?

 

[Brian_D]

You need to figure out why you still have an 02 code. Did you replace the appropriate 02? If so, start checking the wiring. Depending on what reading the ECU is getting from the 02(or lack of reading), the ECU may be prompting an overly rich mixture.

Another possibility is if this is a Vortec motor, the spider injectors may be leaking-a very common problem.

It is a vortec, i was thinking i might replace the spider injectors if it seems like they need it.

Have you checked fuel pressure?

I have not, although the fuel pump was replaced under 2 years ago.

 

[zombiyjay76]

Check pressure before replacing spider, so you don't waste time and money.