One last attempt....need (diagnostic gods here)

[audipcanugo]

I have codes P0507, and P0171. I have replaced the air filter, removed and cleand the MAF. ( ALso I have tried running with the MAF unplugged and idle stays the same....horrible.) I cannot find a single torn hose and I have looked everywhere. The only air noise is coming from the pancake valve....which it is the small hole on it that releases air. Anyways I cleaned that as well. Also, every ten or fifteen seconds usually at my incredibly awesome dying idle...I get this humming sound from the front passenger side of the car (FRONT not REAR). I am at a loss here guys.

[martini]

I have codes P0507, and P0171. I have replaced the air filter, removed and cleand the MAF. ( ALso I have tried running with the MAF unplugged and idle stays the same....horrible.) I cannot find a single torn hose and I have looked everywhere. The only air noise is coming from the pancake valve....which it is the small hole on it that releases air. Anyways I cleaned that as well. Also, every ten or fifteen seconds usually at my incredibly awesome dying idle...I get this humming sound from the front passenger side of the car (FRONT not REAR). I am at a loss here guys.

have you inspected your spark plugs and tested for pressure at the fuel rail?

if you changed the air filter, unplugged the maf, and cant find any leaks - then it sounds like you have eliminated the air path (as long as your confident with your work thus far)... next are the fuel and spark paths..

[audipcanugo]

First off I don't have a VAG Com. What can I do without one...

[eg6siR]

the humming from the front of the car is Secondary air injection pump....

p0507- idle air control system rpm higher than expected

p0171- System Too Lean Bank 1



take off the belly pan and in the front passenger corner there should be a little air pump, that is your secondary air injection pump and from what i know if there is a leak in that system you will get the loud squeal and from what all data says it can cause those codes... the secondary air injection pump was something to look at on both of those codes in the diagnostic tree... lemee know if that helps..

[B6Lovin]

make a boost leak checker and make ABSOLUTELY SURE that there aren't any leaks in the hoses. martini had a bad one in a crank case breather hose that he never would have found otherwise. I also had one where there was a pinhole in a hose that ripped itself open under boost.

best 5 bucks i ever spent was to make one.

the reason i say to go back over the intake system one more time is because that sounds exactly like how my car acted when i blew an IC hose off. shitty idle - then stalling.

[eg6siR]

yea, do a boost leak check to but i'm willing to bet its the Secondary air injections system

[audipcanugo]

Ok well How can I do that test without a vag? Also what Exactly will I be looking for with the secondary pump?

[martini]

http://www.a4mods.com/index.php?page...boostleak.html

[dirtybrd]

I just had that 507 code come up on a GMC Canyon @ work. I cleaned the TB and all was well. Sounds to me like you have a dirty TB and or a bad MAF. Are you running a chipped ECU and if so which tuner?

[audipcanugo]

No I am not chipped....damn well should be but not. And the MAF I'm thinkin is ok...Dirty TB? Car is running very lean. That 507 code I got was sayin RPMS too high. But the damn thing is running very hesitant and the idle is low and sputtering. This has to be horrible for the motor but I told myself I'm not droppin 300 plus anymore on a diagnostic.

[AudiSeefu]

hey man, I am in okc and have vag if you need. let me know.

[audipcanugo]

Thanks I def. will..

[old guy]

You really need to run a pressure test. A P0507 coupled with a P0171 is a very strong indication of a vacuum leak somewhere. The extra air will give you a rough and fluctuating idle and also lean out the mixture causing that combination of codes. It only takes a small leak at idle to cause problems.

[dirtybrd]

Still here huh?

[old guy]

Still here huh?

Just checking in before I go to bed. (Old guys need a lot of sleep, plus 4:30am comes up awful quick!)

[eg6siR]

so you dont suspect the secondary air injection pump for that squeal from the front of car at all old guy?

[old guy]

so you dont suspect the secondary air injection pump for that squeal from the front of car at all old guy?

audipcanugo never mentioned anything about a squeal . he stated that there was a humming sound from the right front. Possible a torn DV? The secondary air pump is only activated for the first 90 seconds of a cold start. I was under the impression that his problem was all the time, not just at start up. Plus the secondary air pump is not part of the intake system. It pumps air into the port on the back of the head to get more air into the CAT during a cold start.

[eg6siR]

yea, you are right, must have misread it, my mind is in a million places right now, and i am working on an a6 with secondary air injection problem right now at work, must have got things a little fouled up in my head... now that i re-read his first post, i completely agree it could be a vacuum leak... wasnt trying to say you were wrong... you seem to be the goto guy around here on AZ... i have read a gazillion of your posts old guy...

[audipcanugo]

Ok I am getting the PVC parts this morning to run the boost leak test. Will that find any leak I may have?

[B6Lovin]

yeah, just follow the writeup on a4mods and you'll be fine -- i recommend using a really good PVC glue though and not JB weld. JB takes WAY too long to dry. (PVC glue takes about 10 seconds to get a good seal)

[audipcanugo]

Oh jesus....I'm screwed. The big hose that goes into the block and into the PCV valve. It had a slit in it so I have been trying to get it off. Now the whole top part that goes right into the PCV has torn almost off. What the hell am I gonna do?

[audipcanugo]

I have no idea how to even get the hose off. It runs under the engine.