Need help : Car not holding boost '' no boost gauge''

[K04-B6]

Hello all,

I've had this problem for the last 4 days and it's starting to drive me crazy. I have done the vacuum line simplification but I've done it in a way that I do not get any CEL. Everything went very well and I have changed all my lines and even my TIP. I have not gotten any CEL due to the fact that I have kept everything important connected. What I have done is reposition my diverter valve into the reverse position and and changed all old vacuum lines. Car ran amazingly for the last week with constant boost, in the last four days I have experienced my dv ''reticulating'' I don't how else to put this but it seems to bounce the air around instead of just releasing the air in one shot.. because this happens my car falls into limp mode. at first I thought maybe my vacuum lines were to big running on the dv and on the n75 thus causing a boost leak, I have replaced those back with the stock lines and problem persists.. I ran a 1 inch line from the dv to the tip.. is this too big? would this be the issue since its too much air?? List of mods are in my sig,

Any help is really appreciated !

[customa4]

A 1 inch line from the DV to the TIP? Why did you do that? That is extremely over-sized and very well could be causing a problem. Don't try to change sizes, keep the same sizes with the new lines. If it were up to me I'd tell you to put it back to the stock configuration but it's your car.

[jjvwg]

1" line from the DV to the tip is fine, thats what i run and its basically the same size as the stock line (probably 7/8" or so). I agree with customa4 though in regards to going back to stock with your vacuum system. no reason to change up the stock system, it works well!

[K04-B6]

The only thing that has changed from the stock system is the bunch of vacuum lines that were near the brake booster and intake manifold. Everything else is stock, N80 is fully hooked up and so is DV and N75. The only code that I do eventually get is P0171 which I have been getting on and off for the last year. This is why I changed the lines.

[customa4]

1" line from the DV to the tip is fine, thats what i run and its basically the same size as the stock line (probably 7/8" or so). I agree with customa4 though in regards to going back to stock with your vacuum system. no reason to change up the stock system, it works well!

Ahh you're right, some reason I was thinking of one of the smaller lines. 1" should be fine.

[jjvwg]

P0171 is a lean code so you probably have a vacuum leak pulling in unmetered air somewhere. I'd go back and check everything you changed. Do a boost leak test and worst case if you can't find anything take it to an Indy shop and have them smoke test it.

[Charles.waite]

Blah blah blah I have done the vacuum line simplification Blah blah blah

I found your problem...

[texasboy21]

I found your problem...

Bingo! Its crazy how 99% of folks who do the vac line simplification have issues after. Its also crazy that completely altering and/or deleting things under the hood causes the car to have issues... Who would have thought??

[K04-B6]

No it has nothing to do with the lines I took out. Like I said there's only about three lines that I took out from the drivers side. This is a boost leak, I put everything back in the car and problem persists... I spent half the day putting it all back together. Car improved a little but now from testing I found out that from under load, lets say 5th gear at 2000\2500 rpm. When I floor it, boost starts to build and then eventually just gets dumped and car goes into limp mode "As this happens there's a high pitched wooosshh sound at the same time''. I'm wondering if its a wastegate issue or my DV...

Smoke test would be the best thing I could try

[customa4]

Have you inspected the suction jet pump at the rear of the engine bay?

[K04-B6]

It's removed and I installed a IE block off plate. My SAI is deleted with Ohm resistor in place. I do not have cel for this simply because my tune must have it written out.

Have you inspected the suction jet pump at the rear of the engine bay?

[ozMatt]

No, he's not talking about the SAI - he's talking about this: https://www.ecstuning.com/Audi-B6_A4...ions/ES252639/

Have you still got it or did you remove it when you "simplified" the system? They are prone to split in half causing a massive vac leak.

Because we don't know how you have changed the system exactly, i would suggest going over every piece you changed, and for any that you haven't changed, check that they weren't broken whilst you were ripping the other stuff out.

**EDIT: you replaced the TIP? check that it is connected properly to the front of the turbo.

[Charles.waite]

facepalm.jpg.

Dude, I'm sorry to be the bearer or bad news, but that SJP, and those check valves and those vacuum lines you removed? Yea, those. You kinda need those.

And yea I was being flippant above, but also truthful. Audi engineers didn't just slap those hoses in there to fuck with enthusiasts. They actually serve a purpose...

[ADCS]

^Clearly the engine is way more reliable with all that crap removed....

[K04-B6]

Boost leak test clarified that 1: I'm an idiot and 2: something needed attention. For my "simplification" I should have clarified that I did't exactly remove everything, I simply re- routed it so that the engine bay appears more open... With that said I have found that I hadn't put a clamp down on one of my hoses coming off the DV... I feel stupid yes lol also when I put all the old stuff back I found a leak in the hose running from the block to the valve cover. I have temperalily fixed this issue and car runs good. Now to place an order for the right stuff.

Thanks for any advice.

I don't make changes to my car before knowing what i'm doing so I made my own version of the "simplification" and it works.