OBD 2 Codes... Little Help Please

[BoLoMaN]

Well, the dread "Check Engine" light has come on in my 96' Town Car. I ran a quick scan with my friends OBD2 Scanner. So far these are the codes that have come up:

171 - Heated oxygen sensor indicates lean condition, left side

174 - Heated oxygen sensor indicates lean condition, right side

308 - Misfire in corresponding cylinder (8). Check ignition and fuel system.

1131 - Lack of O2 sensor switch, lean (1/1)

1151 - Lack of O2 sensor switch, right bank sensor 1 (2/1) lean

Just so you know I've changed the plugs, wires, and front 02 sensors. The car is running sh*ty as hell. Sputtering, loss of power without warning, WOT is useless, 14 MPG, and a few other kinks I can't quite think of now.

Can anyone here shed some light into what those codes mean (obviously I know what the 308 is about - probably a little bit of carbon build up or a speck of dirt on the plug that's causing that - I know I can take care of that)? I know I have some bad cats so I'm planning on fixing that, but was also thinking of a whole new exhuast system as well. Anyone have any reccomendations?

Really want to get my girl back on the road, and I'd prefer doing most of the work myself seeing as my pockets are hurting from gas prices (poor college student with a Town Car as a daily - OUCH! Still love my Lincoln though)

Thanks in advance guys,

-Jimmy

 

[MichiganTeddyBear]

you say the cats are bad.... could they have melted down and are restricting the exhaust???

just a stab in dark.. I don't drive obd2 vehicles....

 

[immusicman]

codes

Hi, looks like to me you probably have a converter stopped up, or..a dreaded vacuum or intake gasket leak. Take starting fluid and once the engine is running..spray it all around the intake and vacuum ports and hoses..soak them while the engine is running. IF the engine idles up and smoothes out while doing this, then you have found your vacuum leak. the lean conditions are almost always caused by vacuum or intake gasket leaks. However, a stopped up converter could potentially do it also. Also, if you have changed your front o2 sensors, change the rest of them..It really is important to change the back ones too. Why? Because there reaction time is probably slightly slower than your new ones...can definitely set the codes..I would first check for vacuum leaks...if you find nothing..tend to that exhaust and if that fails, change the rear o2 sensors..now if you still have the problem..you need to check each injector individually. unplug them and check the resistance..you will have to get a book to check what the values of each injector should be unplugged. If they are ok, you need to unplug each injector one at a time and install a noid light...make sure each plug is pulsing the light when the engine is cranked. If all this turns out ok, you probably have a mechanical valve issue and it should be fairly easy to find by checking each spark plug for the evidence. hope this helps.

 

[BoLoMaN]

big thanks. will do everything mentioned.


yeah obd2 can be a pain in the neck... but it can be a tuning marvel as I've noticed with many Nissan and Honda boys.

 

[Kiss4aFrog]

Starting fluid? ? ?

You might want to rethink that idea. Starting fluid is a little too flammable to be shooting around the engine compartment near the exhaust manifolds and maybe a stray ignition spark. How about using carb cleaner. You get pretty much the same effect if you hit a leak plus is less likely to burn down your engine in the process. You can also put the extension tube on and then you narrow down the area you are testing rather than starting fluid which would just blast out over a large area.

I do agree that it does sound like an intake leak may be your culprit.

Just a thought.