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Kunundrum
12-08-2007, 07:55 AM
hey guys

I think my turbo is shot...

thursday night I realized that the car was slower than normal so when I got home from work I tossed in my boost gauge very quickly. and found ZERO boost pressure... [confused] so I figured the DV was bad as it is a common culprit in chipped cars and mine was still the stocker.

droped it off to have that put in and have a pressure test, the DV was diagnosed as being bad, In goes a 710n. now I have boost... all of 4psi though... WTF ? checked the wastegate it's appears to be fine.

Shop is saying it either Cat, Turbo or MAF... great...[=(]

so today I cleaned the MAF, with MAF cleaner, and gave the car a Seafoam treatment.

the seafoam cleared some of the carbon out of the car but still no boost over 4psi.

I'm thinking the Turbo is gone, any other things I should check ?

On a second note does a B6 K03 Fit a B5 ?[az]

ILoveT
12-08-2007, 10:12 AM
Nothing is wrong with your turbo unless you hear screaming kittens. Pressure test the system to check for leaks. If its not that check to see if your N75 is bad. When that isn't working properly you can only see around 4 pounds. If you can get your hands on a smoke machine that would help narrow down your search radius inside the engine bay. And its really fun to use.

Kunundrum
12-08-2007, 10:56 AM
the shop I took it to did a pressure test and it passed with flying colours (once the 710N was installed)

N75 valve you say... hmmm... Any diff between N75F or N75C ?

ILoveT
12-08-2007, 11:34 AM
Both are the stock valve.

Kunundrum
12-09-2007, 12:15 PM
probably should get a N75J ? ...since I'm chipped ?

Poopie
12-09-2007, 12:23 PM
Sounds like a maf problem throwing you into limp mode. Did you scan the car for codes

ILoveT
12-09-2007, 12:31 PM
Don't replace parts unless you have to. No use spending money until you KNOW what the problem is. At least thats what I do because I'm poor.

anonymous6915
12-09-2007, 01:12 PM
i have the same problem...i was throwing a p0171 and thought it was the maf so i cleaned it n it came back...i got another one from a user on the forums but still not ok now im hearing that it could also be the o2 sensor so u might have some luck trying those...im still looking to find some for a good price...i dunno but that might help...

ILoveT
12-09-2007, 01:17 PM
I thought Mike told you the O2 sensor wouldn't cause boost issues?

anonymous6915
12-09-2007, 01:44 PM
yea i read that too but i also read in another thread taht a p0171 could b caused by either a bad maf, boost leak or a faulty o2 sensor...and since he doesnt have a boost leak and it probably isnt the maf i was just suggesting the o2 sensor...kunundrum...you should pull your codes to see what you got...

Poopie
12-09-2007, 01:47 PM
unplug the maf and see how your car runs. On a 01 it will base your timing and fuel maps off the MAP sensor.

Wakeboardosurf
12-11-2007, 07:47 AM
Im spreading the holy news about cats

If you have a stock cat, and the turbo only pushes about 4 pounds, and sounds a little different(exhaust wise) its MIGHT actually be your cat. id get a testpipe for sure too i was you. But anyways the reason its the cat is becauseeeee

The material in your cat is a honeycomb, if it gets broken loose it WILL cause a major exhaust flow restriction usually only keeping the boost at around 5 pounds, mine fluctuated a little because i took off my cat again and it went from 7-8 pounds to 5 pounds.(this was before i knew the cat was my problem!!!) and when i say take off i mean just onbolt it from the turbo.

My car sounds like more motor than anything.

Luckily ive got a testpipe in my garage, now to install........

anyway ive heard if you take out idk which one but one of your 02 sensors and go wot and it boosts more, then i think we have an answer

Kunundrum
12-11-2007, 08:32 AM
we have been running codes all the time, there are no MAF codes, The N75 Was bad, but it still have not solved my boost issue. I Ordered a new cat and should be here tomorrow or the day after. we unplugged the vacume line leading to the waste gate and went for a drive, this should cause the turbo to boost uncontrollably... not the case.

I'm in the process to get a new N75 valve as the one they installed was a spare one lying around the shop.


so I am hoping the cat fixes this damn issue...

So far
- Bad DV
- Bad N75
- Bad Cat (?)
------------------
Still no Boost....

Wakeboardosurf
12-11-2007, 09:16 AM
yes it is the cat def! Take it off, and good luck with that btw hahaha. if you can figure out a way to magically get it out let me know) BUT YESSSSS CAT CAT CAT

i wouldnt order a new cat dude, go here http://cgi.ebay.com/Testpipe-Test-Pipe-Downpipe-Catless-Audi-B5-B6-A4-1-8T_W0QQitemZ330196884256QQihZ014QQcategoryZ33633QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem

Youl see like 500 rpm sooner turbo spool, ANDDD about 15 hp!

Youve got to get sparkplug antifoulers though, your AEB engine right?
AND i know il pass inspection without a cat :) i brought my laptop and cleared the codes right before hand. Only done it once, it worked though. But antifoulers help not throw a CEL so you should still be fine.

Wakeboardosurf
12-11-2007, 10:01 AM
TAKE OUT YOUR FRONT 02 SENSOR RIGHT THIS SECOND, like DONT THINK ABOUT IT. GET UP AND DO IT!!!! i just did and wow, up to 10 pounds. My cats bad for sure and im guesssing yours is to. its such a relief and its just such a simple test!!!!

GO TAKE OUT THAT SENSOR AND TAKE IT AROUND THE BLOCK!



its crazy how many people are having this problem right now, like i was this morning, right where your at now

Kunundrum
12-11-2007, 10:34 AM
Unfortunately I can't get a test pipe because of emissions laws up here (It's illegal to remove a cat) so I ordered a Direct Fit cat for $160.

I will try the O2 sensor trick when I get home (At work now)

anonymous6915
12-11-2007, 01:10 PM
wait i acctually am throwing a p0171 code...and i think its my o2...are you saying that it could be my cat? and if i go and take out my o2 sensor b4 the cat and clear the code...i will be fine?...or does this only pertain to pp who just dont see boost without a cel?...im already getting a hfc with a new exhaust next week so if this will solve my problem then i dont have anything to worry about...

Wakeboardosurf
12-11-2007, 02:13 PM
wait i acctually am throwing a p0171 code...and i think its my o2...are you saying that it could be my cat? and if i go and take out my o2 sensor b4 the cat and clear the code...i will be fine?...or does this only pertain to pp who just dont see boost without a cel?...im already getting a hfc with a new exhaust next week so if this will solve my problem then i dont have anything to worry about...

Oh im just saying the CAT is whats causing the low boost, the CEL idk without looking up that code, But the CEL (since u ran the car with the wastegate slosed) has nothing to do with the boost.

As soon as the HFC comes in youl be fine!!

Poopie
12-11-2007, 03:02 PM
the car would more then likely throw a CEL for the o2 sensor if it was a clogged cat. The easy way to diagnose it is do some WOT runs and if the cat is glowing red hot then you know its bad.

I still think its the MAF. Did you drive your car with it unplugged? You should run a log of your car too.

SpyderSE2
12-12-2007, 01:36 AM
the car would more then likely throw a CEL for the o2 sensor if it was a clogged cat. The easy way to diagnose it is do some WOT runs and if the cat is glowing red hot then you know its bad.

I still think its the MAF. Did you drive your car with it unplugged? You should run a log of your car too.

My clogged cat never threw a code, made it that much harder to diagnose.

Wakeboardosurf
12-12-2007, 10:23 AM
my cats clogged and my dash clear, it didnt throw a cel for me.