Warning Light

I have a 96 Ram 1500 with 318. It has 46,000 and check engine light just came on. I was about to do a general tune-up on it because my mileage has dropped from about 400 miles per tank to 370ish. Would anyone else do the tune-up to see if this corrects the problem before taking it into the shop?

No I wouldn't unless you are due for it.There is a problem somewhere,and you'll need the dealer to hook up the DRB-3 scan tool to read the code(s).I'm not going to guess on what it could be,there's a lot of codes.

Thanks, Christopher. Ended up being a bad O2 sensor.

many times o2 sensors are replaced due to a ritch or lean code, these codes are usually set whein the ECM (computer) detects a lean condition and commands to go ritch but does not, or vice-verca

All I am saying is dont be supprised if the
SES (Service Engine Soon) light comes back on in a week or two if that is the reason the 02 was replaced, you may have another problem