My k03 is dead

**CbassB5** · 11-14-2008 06:42 PM

well i have a 2002 a4 1.8T and I had the diode mod pushing out 19psi for a few months. Then I started to hear a whining noise and I just assumed it was a boost leak because it dropped to 15psi. Then today it just showed me 0psi and figured I must have a huge boost leak (but in the back of my mind I already knew the turbo was toast

) and continued driving until I saw my blue smoke screen coming out of my car and realized it's game over.

So my question is can I salvage the turbo and buy a rebuild kit or am I going to have to find a rebuilt or used k03/k04. I don't have money to spend so I want the cheapest solution and I need my car to get to school so I'm stuck.

**jackyaudi** · 11-14-2008 06:49 PM

Cheapest solution? Look for a used Turbo in the Classifieds in your area.

Even cheaper? Call up the scrap yards in your area for a B6A4 used K03 Turbo and take it out the salvaged car and put it on yours.

Take a look on ebay too, u never know.

**absolutegtr** · 11-14-2008 06:51 PM

Sent you a PM

**CbassB5** · 11-14-2008 06:55 PM

Thanks for the quick reply and suggestions, I guess I'm going to look around

**B5A4Kevin** · 11-14-2008 08:03 PM

i had my k03s rebuilt for 250, but you can find a used one cheaper and also not worry about down time. only downside is you dont know how long the seals or thrust bearing will last in the used one.

**04_A4_1.8T** · 11-14-2008 08:15 PM

newb question whats the diode mod?

**durfA4** · 11-14-2008 09:20 PM

just a word of warning from my previous experience, the diode mod works to let you run what ever boost you want, good for the most part, but it has a couple drawbacks

first of all the diode mod is a simple work around to prevent the map sensor from reading over 17 psi (going from memory) by placing a $5 diode in the wiring that limits the voltage that sensor sees.

Boost- The k03 can only provide so much boost at xRPM so if ran off a manual boost controller you can push the turbo to overspin and reduce the life span of the bearings, you learned this lesson. the reason the chip companys can get more boost is that they adjust the n75 valve constantly to keep the boost pressure optimal based on the map sensor, which is now negated by the diode. this is just hurting the lifespan of the turbo and not providing optimal performance but is a cheap way to make a few hp.

the really bad part of the diode mod is if you have an issue with your MAF then your engine is running off the 02 sensor only. which is fine for open loop driving, but full throttle will use those setting and can cause a unsafely lean condition even with a k03. maybe not a blown engine but melting of the Cat-converter or pistons rings, valve seats etc...

so if you have a large turbo that you can keep in its efficiency range and want to maintain the diode mod it can work, but on the smaller turbos the money you spend to replace the turbo is more than the cost of the chip.
fiscal lessons learned are often the toughest.

now if you were planning on a upgrade and needed to convince the wife/girlfriend that you "needed to spend X amount on a turbo upgrade then you are not alone my friend.

**QuattroRocket** · 11-14-2008 09:55 PM

I have a perfectly good K03 if you need. 30,000 miles on it before I went BT.

**yung turbo** · 11-15-2008 12:53 AM

Originally Posted by durfA4

just a word of warning from my previous experience, the diode mod works to let you run what ever boost you want, good for the most part, but it has a couple drawbacks

first of all the diode mod is a simple work around to prevent the map sensor from reading over 17 psi (going from memory) by placing a $5 diode in the wiring that limits the voltage that sensor sees.

Boost- The k03 can only provide so much boost at xRPM so if ran off a manual boost controller you can push the turbo to overspin and reduce the life span of the bearings, you learned this lesson. the reason the chip companys can get more boost is that they adjust the n75 valve constantly to keep the boost pressure optimal based on the map sensor, which is now negated by the diode. this is just hurting the lifespan of the turbo and not providing optimal performance but is a cheap way to make a few hp.

the really bad part of the diode mod is if you have an issue with your MAF then your engine is running off the 02 sensor only. which is fine for open loop driving, but full throttle will use those setting and can cause a unsafely lean condition even with a k03. maybe not a blown engine but melting of the Cat-converter or pistons rings, valve seats etc...

so if you have a large turbo that you can keep in its efficiency range and want to maintain the diode mod it can work, but on the smaller turbos the money you spend to replace the turbo is more than the cost of the chip.
fiscal lessons learned are often the toughest.

now if you were planning on a upgrade and needed to convince the wife/girlfriend that you "needed to spend X amount on a turbo upgrade then you are not alone my friend.

so this has me thinking; would it be possible to use the diode mod to lets say a GTRS with correct injectors, would it be possible to drive like this without a chip? because it sounds to me like this diode mod defeats the whole purpose of havin a chip in the first place.

**texasboy21** · 11-15-2008 01:09 AM

^^^ive been googleing that exact same thing......havent found anything. But i too have done the diode mod, and i cant tell if my turbos on the way out but i want a BIGGG ONE!!! im considering a 50trim kinetic or rotomaster with manifold, then mod the software and motor internals down the road. Im talking 12-15psi here, nothing crazy, but itll have to do for up to many years to be 100% complete...hope hope hope lol

barrett

**durfA4** · 11-15-2008 07:14 AM

the whole point of a chip and a tune is to allow the injectors the right calculations based on the amount of boost that the turbo will build up to.

you SHOULD NEVER bolt on a bigger turbo and not get a CHIP/Tune.

the ecu is more complicated than most other companies and has very small adaptation windows. so if you change the injectors and then diode mode the the MAP sensor your MAF readings will not match the injectors.

you will get a rich idle and a lean WOT the worst combination.

the money you save do this diode WILL be lost when you blow your engine, the diode mod is a band aid, to allow more boost than specified by the ecu, but if you look at all the BT and larger turbos on this board None run a Diode Mod, because it will not allow the ecu to effectively calculate the A/F ratio.

I do not understand why any one would be willing to spend so much money on a turbo, and then skip the part that will allow it to perform optimally.

**texasboy21** · 11-15-2008 08:26 AM

^^^relax man breathe. I am not trying to be some radical nor am i disagreeing that a bt with proper software is optimal, all i was asking was if it could be done relatively safely, that is all. and i guess the answer is no lol

barrett

**widgget** · 11-15-2008 10:01 AM

if it was tat easy noone would buy software.

**absolutegtr** · 11-15-2008 10:45 AM

I am just doing the diode mod, because there is no point to buy software now (I would have to ship ECU out for god knows how long and I need my car EVERYDAY)

When i go with a bigger setup, then it will be "worth" having to live without a car while the ECU is out....

I honestly dont see anything wrong with the diode mod if you are SENSIBLE with it.