engine light comes on show lean feul mixture

[slerby1st]

1998 3.8 supercharger i have replaced front O2 sensor and engine light still comes on and shows lean fuel mixture. i have to have light reset every day and it still comes on showing the same code. can anyone help solve this problem before i go insane. Thanks

[azu]

Could be several things. Check all vacuum lines as usually this is an indication that air is entering the combustion chamber that is not metered.

P.S.

Make sure that your plug wire(s) are not touching the O2 wire!

[Bob Dillon]

Change the fuel filter.

[slerby1st]

Thanks for the advice i will see if this solves my problem.

Changed filter and will see if it helps... anyone know if engine light can be reset without diognostic tools...tried battery disconnect and it did not work.

[imidazol97]

I agree with the air leak. Check those vacuum lines for rot or cracks where you don't see it. . Try some carburetor spray around the hoses and the intake manifold around its edges while the motor's running and listen for a change in idle if it sucks in the combustible spray.

[azu]

Thanks for the advice i will see if this solves my problem.

Changed filter and will see if it helps... anyone know if engine light can be reset without diognostic tools...tried battery disconnect and it did not work.

I believe over time if no problems exist it will go out, but I could be wrong. You might want to invest in a scanner for OB II. It will last you a life time(Unless an OB III comes out). You could always go to an AutoZone and have them reset and see if it comes back.

[slerby1st]

light did not go out but i changed pcv and added fuel additive to gas and light went out for two days then when fuel gauge read half the light came back on. Still wondering what to do.

[willwren]

Fuel additive is a waste of money. The same detergents are already in your fuel.

Please check your fuel pressure by attaching a borrowed/rented/purchased fuel pressure gauge to the test fitting on the fuel rail. We need to know the pressure at:

1. Key on for two seconds, off, on for two seconds, off, on for two seconds (3 two-second primes). What's the pressure?
2. At idle.
3. At idle with the fuel pressure regulator vacuum hose disconnected and plugged (plug the rubber line).

How old is your O2 sensor, and what does your exhaust smell like?

[swampthing]

also i think that with some SES lights if it does not detect the problem in three cycles it will shut off

[slerby1st]

I checked over for vaccum leaks and came across two, one for pcv and one for throttlebody. I changed both and replaced pcv and cleaned throttlebody. When I pulled off the throttlebody it was clogged up with carbon soot. I also changed the spark plugs, so far the car runs better and the engine light is off. Crossing fingers that problem is solved for now.

[raymwr]

and what does your exhaust smell like?

We might not wanna go there.

lol

[willwren]

Ray, that's a very good way to determine if he's running overly rich, or has a gasket failure and is burning coolant. We try to keep the BS out of the Mechanical topics.

[slerby1st]

Exhaust does not smell, except for normal and does not seem to be white or blue in color.

[raymwr]

Ray, that's a very good way to determine if he's running overly rich, or has a gasket failure and is burning coolant. We try to keep the BS out of the Mechanical topics.

Sorry i guess i forgot what forum I was on.