Possible Exaust Leak / Running Rich

[INHUMANITY]

I had the airbags on the rear of my Yukon replaced last month. The guy took it for a spin and said he noticed an exhaust leek coming from under the hood.

I never thought much of it as I figured it was just the aftermarket exhaust doing its thing.

During the past few days, I have noticed that I can hear the "exhaust" coming from the front bottom of the truck. It is hard to explain, but if I am driving next to a car or a wall, I can hear the exhaust right by the driver’s seat.

If it helps to know, when idling the exhaust smells like it is running rich. I have an AIR/FUEL gauge that almost never is STOICH. It likes to hang in lean almost all the time.

When I initially purchased it when going WOT it would back fire and I would get gray smoke from the pipes. I had the plugs, cables, rotor/cap replaced a few months ago which seemed to have fixed the problem.

Yesterday I went WOT for fun as I had not done it for a while and the backfire and gray exhaust is back.

 

[mygreen98]

no check engine light? very lean or very rich will turn on the light. do you access to a scanner ?

 

[INHUMANITY]

You know I think my Yukon doesn't have a factory check engine light.

There appears to be an orange light that the previous owner mounted in the gauge area that seems to fire up and off when I start the truck.

Very similar behavior to a SES light. But alas, it doesn't light up.

I may just purchase an OBD-II kit. You get a ODB-II to USB adaptor that works in conjunction with free software that gives you all the skiny on your car.

This is the guys' site: http://obddiagnostics.com/

Anybody else have any ideas?

 

[mygreen98]

it has to have one from the factory. whether or not it was removed is a different story. it should be in the top left corner of the instrument cluster. with key on engine off, the light should illuminate, if noe its either burnt out, or removed. checking for codes is a necessity to get to the bottom of your problem.

 

[96ProCompTahoe]

i'd put my money on it burned out or it was removed. did you buy it with the blower already on it? it may have kept it on for whatever reason, just a thought.

 

[mygreen98]

probably right, blower was kicking on ses light , so someone pulled it.