What Exactly is Limp Mode?, Can anyone explain this? Options

[Lil-Joe101]

Temp gauge is fine, not rising or standing, it reads normal temp. Looked up Signs of a bad o2 sensor and got this:

Sudden decrease in fuel mileage. A defective O2 sensor will likely cause your air-fuel mixture to be too rich and directly affect your fuel economy.

Flashing check engine light or malfunction indicator lamp in the vehicle?s dash board. Of course this can happen for other reasons as well (and a defective oxygen sensor is one of them!) (Im having this issue, not flashing, but is on)

Failure to pass smog. According to the EPA (Environmental Protection Agency) and CARP (California Air Resource Board) 50 to 60% of all smog test / emission test related failures are attributed to defective oxygen sensors, causing either low or high CO emissions.

Overall poor vehicle performance; rough idling, stalling, hesitation on acceleration, etc. (Im having this issue)

Also looked up signs of a bad engine coolant temperature sensor signal and got this as well:

Potential symptoms include:
•MIL (Malfunction Indicator Lamp) illumination
•Poor fuel economy
•Poor drivability
•Engine may run rough or blow black smoke out the tailpipe
•May not idle
•May start and then die

(Im having all these symptoms)

Also I noticed my speedometer doesnt work and neither does the background light to it. Tach and tach background light, fuel level, engine temp and background lights all work fine.

This post has been edited by Lil-Joe101: Mar 23, 2014 - 11:05 AM