hi, i just changed the Mass Airflow Sensor on my 01 Land Rover Discovery II. It was working just fine till i added some fuel treatment and fill it up with gas. now when i start it it turn off by it self if i don't press on the gas. when i press the gas for about five minutes, i can see a lot of smoke coming under the car. when i look under i can see the portion of the exhaust located between the first and the second sensor is red like it's on fire. its the one on the driver side. please can anybody help me out? any help will be greatly appreciated.

 

......
......
......

Seriously though it's never good to be reving the engine for 5 minutes without moving, ever.

 

do you think that might the cause?

 

Sounds like your getting I burnt gas on that side.

 

what is a burnt gas on the side?

 

Why the he-- would you rev for five mins?
Does it do this after driving around?
Your cat could be clogged up?
How many miles?

 

It has 110k miles on it and when i try to drive it around it barely goes up to 40 mph. i tried to rev it just figure what was causing the black smoke that was coming from the exhaust. it was already malfunctioning before i tried rev it.

 

Oh God. Sell that thing it's probably screwed.

Seriously, change sparks, plugs, and maybe coil pack. You probably need a new Y pipe with new cats.

 

i just changed the spark plugs and wires. i did and oil change. the car was functioning properly before i added the gas treatment.

 

The "glowing red" section between the O'2 "sensors" contains your driver's side catalytic converter. From what you are describing it sounds like the outlet side of the converter is plugged. It's glowing red!? DO NOT DRIVE IT OR START IT until you remove the Y-pipe and check on the state of the cat.

No clue how it could have gotten plugged from a M.A.F. change and a gas treatment additive.