ChaoticS4

I'm getting boost spikes on stg 1 software and k04's in my a6 2.7t.

Could the N75 be the issue with this? Would a manual boost controller work in fixing this problem?

It is a 1 bar chip that spikes to 1.5 bar in the middle of the power band in 3rd and 4th gear.

Mods on the car are as follows.
k04 turbos and associated piping.
apr bipipe
stg 1 software
no dp's no exhaust.
That's it in terms of engine mods.
The car is a 2002 with 8k miles on it.

Someone please help me!!

ChaoticS4

No one can help or has any suggestions?

seattle audi

Re: Have you posted this on the S4 forum? They're "mod freaks" over there.

2.7tDallas

true - not going to get answered here

GIACUser

If you are getting boost spikes while on throttle ... you should look at your wastegate. May be sticking, may be hitting something.
As you stated and I tend to agree, that if you are not getting spikes off throttle it is less likely to be the BPV's. I would however just replace them if you have not, just because.

1.5 bar spikes must be fun with KO4's.

The wastegate is generally the control mechanism for boost. It is supposed to act on instruction from the ECU. Assuming you have a chip designed for the flow characteristics of your KO4's I would suspect wastegate, not the program.

My .02

StoneMan

That doesn't even accurately convey the reality!

ChaoticS4

maybe I'm wrong. was hoping to get some answers to this issue.

Anyone else?

Oh.. hehe ... I know how we S4 owners can get... I've been on their forums for over 3 years.

This A6 is actually a friends that is having issues.

fl2.7T

Thus, K04s as replacements (w/stk ECU) isn't as plug&play as some have indicated?

GIACUser

They are an easy upgrade because they bolt right up to the existing manifold, it is quite common to need a new manifold or adaptors to put on different turbos. But bolting on bigger turbos and leaving everything else the same doesn't make sense to me. My assumption and anyone please correct me.... is that when they write the program it is written for a particular flow at particular psi. With KO4's you are able to flow more air at lower psi because its a bigger fan. New things are going on and values/assumptions that were once valid are no longer valid. Which is why I believe it would be beneficial to use a program written with the KO4s in mind. For obvious reasons it is important to maintain proper air/fuel ratio. With bigger turbos and more air you need more fuel. Lean conditions (too much air and not enough fuel) can quickly toast a motor. Having said that I think that KO4 upgrade with the OCT program to go with it is one hot setup. I have driven one and it works very well. It isn't exactly plug and play because you have to remove the motor to install them but the intake system, fuel system, intercoolers, engine cooling system, exhaust etc all have the enough capacity to benefit from the upgrade which bolt up to existing manifold so as turbo upgrades go it is a very very easy one.

fl2.7T

For example, even if I could get "more reliable" KO4s as replacements on a CA 7/70 emissions warranty basis, increased turbo lag/low end perf are not the "only" issues. One c/b creating probs (using the stk ECU) or even bigger issues in trying to match an aftermkt chip with a "garden-variety vs enhanced" K04.