dwash202
LVC Member
aww man i got '97 with a check engine code p4011 (Secondary air injection fault). Does anyone eles have or had that code? what does that mean on a Gen II?
check egine light on
- Thread starter dwash202
- Start date
thaywood
Dedicated LVC Member
I have a Gen I 1996 Mark VIII with the same problem. My code is "Auxilliary Air Injection Reverse Flow Detected". From what I have been told, this could mean several things. It could mean the electric smog pump located behind the front bumper cover on the driver's side is malfunctioning. Or one of the smog pump and/or emission control solonoids or relays is bad or malfunctioning. The only way I know to know for sure is to get a dealership to do a pinpoint OBD II check on the computer. If that doesn't work, you just have to replace stuff untill the light goes out. I have a new smog pump for mine, but I haven't had time to install it yet. Maybe that will work.
Jibit
Dearly Departed Friend
isn't that when the pump blows fresh air into the 02 upon start up? You sure the 02 isn't bad? How many miles are on the car and have you ever replaced the 02's?
Dern Humpus
Dedicated LVC Member
Something to do with the air pump and injecting air into the catalytic converter would by my guess.
dwash202
LVC Member
the car is going on 160k this month so how much money am i looking at to get that light off.
Frogman
Dedicated LVC Member
- Joined
- Jul 11, 2005
- Messages
- 6,987
- Reaction score
- 1
Again, DEPENDS on the problem. As these guys said, it could be the fresh air pump, it could be a bad O2 sensor (though, I think it would throw its's own code)
Alternately, just get an Xcal 2 and turn all that emission crap off.
Alternately, just get an Xcal 2 and turn all that emission crap off.
thaywood
Dedicated LVC Member
Usually, if it is an oxygen sensor problem, the OBD II diagnostic will tell you it is an O2 sensor fault. The OBD II diagnostic is usually very accurate, if you know how to interperet the codes and/or explanations of the codes. My "air injection reverse flow" problem has me stumped, though. The smog pump doesn't inject any air into the catalytic converters that I can see as there are no extra tubes or pipes going into any of the three cats. The emissions control system is basically a bunch of hoses and gadgets located in front of the engine toward the bottom between the crank pulley and the radiator. I can't really see that it does anything really usefull. It's just something else to go bad and cost you a big fat pile of money to fix.
Roadboss
Dedicated LVC Member
Also check your gas cap. Alot of these codes show up when peeps don't tighten up their gas cap after fueling. Some times they leave it loose or the cap seal could be shot. Either way it's no big deal as the purpose is to aid emmisions at startup by injecting air into the exhaust system. Clear the codes and recheck the cap. My Gen l 96er has the pump removed totally.
thaywood
Dedicated LVC Member
So you can remove the smog pump completely without any codes showing up? That's cool. I think I get rid of mine this weekend. Thanks!
chicken
SHEOOOOOOOOT
no no no, you can only remove it if you have a flash tuner where you can turn off all the emissions crap, and look at roadbosses setup its far from stock
if you just pull it off you will get a CEL
thaywood
Dedicated LVC Member
Where do I get a flash tuner and how much does it cost?
Roadboss
Dedicated LVC Member
You will also need to plug the holes in the exhaust manifold or block the lines off. There are several vendors on this site that can burn a chip for you or supply you with a tuner packadge.
Jibit
Dearly Departed Friend
or could just get the kooks headers for a Gen I because they don't exist.