Diverter Valve

[ajehoti]

I believe the diverter valve in my car is failing. At partial throttle it sounds like its releasing many times, like surging. The car has the K04 upgrade and many other things. Mikes old car.

Is it more than likely the Diverter valve or something else?

APR told me not to waste my time on Forge products and just get the upgraded OEM piston type Diverter Valve.

Anyone have other opinions? Thanks

[Alex1188]

I believe the diverter valve in my car is failing. At partial throttle it sounds like its releasing many times, like surging. The car has the K04 upgrade and many other things. Mikes old car.

Is it more than likely the Diverter valve or something else?

APR told me not to waste my time on Forge products and just get the upgraded OEM piston type Diverter Valve.

Anyone have other opinions? Thanks

Surging as in while giving it gas or when you let off..? if its surging while in gas could be due to to much air or boost getting putting into the motor, small over boost. Im pretty sure mike got the heads ported on the car, and i know APR doesnt support that on the K04 tune, so that would be my guess...

The reason i say this is, when my wastegate actuator went bad and i did ALOT of logging and adjusting with Forges Wastegate actuator and a modified OE one, when the wastegate was to tight causing crack pressure to be to high the diverter valve would flutter on partial throttle to bleed excess boost pressure off acting as a fail safe, wouldnt causing any type of code either...

[ajehoti]

Surging as in while giving it gas or when you let off..? if its surging while in gas could be due to to much air or boost getting putting into the motor, small over boost. Im pretty sure mike got the heads ported on the car, and i know APR doesnt support that on the K04 tune, so that would be my guess...

The reason i say this is, when my wastegate actuator went bad and i did ALOT of logging and adjusting with Forges Wastegate actuator and a modified OE one, when the wastegate was to tight causing crack pressure to be to high the diverter valve would flutter on partial throttle to bleed excess boost pressure off acting as a fail safe, wouldnt causing any type of code either...

Thats exactly what is happening to me, the partial throttle flutter. How do I fix this? Someone told me diverter valve upgrade but these cars come with upgraded piston types dont they? Its quite annoying and I want it fixed.

What do you think about this?? http://www.purems.com/Products/T9351...Diverter-Valve

[Alex1188]

Thats exactly what is happening to me, the partial throttle flutter. How do I fix this? Someone told me diverter valve upgrade but these cars come with upgraded piston types dont they? Its quite annoying and I want it fixed.

What do you think about this?? http://www.purems.com/Products/T9351...Diverter-Valve

I have that product from GFB, great product but not gonna fix what your talking about... Your problem is due to the cylinder heads being ported and allowing more air to enter than the cars ECU is tuned to handle at partial throttle, thus causing a slight overboost, that is were the DV kicks in as a fail safe and bleeds off that excess air or pressure. Is the car still have a tune? sounds like it has stock tuning. Not sure if carmax may have updated the ECU or removed the tune while they had it...

[Alex1188]

Edit sorry just looking back on his thread, disregard the cylinder head thing, but since the car does have K04 on it, i would make sure the tuning is correct for the turbo...as the larger turbo on stock tuning would have this effect as well, and that the K04 wastegate has a slightly higher crack pressure.

[ajehoti]

Edit sorry just looking back on his thread, disregard the cylinder head thing, but since the car does have K04 on it, i would make sure the tuning is correct for the turbo...as the larger turbo on stock tuning would have this effect as well, and that the K04 wastegate has a slightly higher crack pressure.

It has the APR tune and I switched it over to the 93 octance S3 K04 file. Ran much better than stock. Oh lord it was horrible prior to that. The DV was also relocated and has a silver plate on the back of it with hoses extending away from the turbo looks like. See if I can snag a photo later for you. I just feel like that DV is no good, it could be the earlier style with the plastic plunger on it.

[Alex1188]

I was wrong he did do some cylinder head work...

The new timing chains, guides, tensioners all went in. The new pistons and the IE rods are in...





The cylinder head is being completed at the machine shop now with new seals, flow enhancements/porting. Hoping to have that back next week and have this buttoned up in 7 to 14 days.

Mike

Great news today. Just got off the phone with the machine shop and the head is done. It should be breathing a lot better.

For the block, all it needed was a slight honing. Otherwise it looked great.

I hope to be done with this by the weekend. Now i need to get an appt at USP Motorsports for the flas.

Mike

I'd really like to see if APR will work with me to maximize their K04 software. I'd love to see what it can do with the head porting and a good FMIC and maximizing the boost.

So this could have alot of effect on the APR tune and not being made for cylinder head porting...

[ajehoti]

He mentioned it did not flutter like that before. I spoke to APR and said they can not help me tune the car. Idk what else to do now.

[Alex1188]

also here... this is the biggest indication of why i say what i said...

It runs well. The only issue I have is a slightly rough cold idle and some hesitation at gear changes. This is slight but I notice it. The other issue is that at exactly 130mph it will go into soft limp with the epc light on and it throws an overboost code. I need to do logging under those exact conditions. I am doing my first oil change soon and then i'll hit the 1/4 mile.

Mike

[ajehoti]

also here... this is the biggest indication of why i say what i said...

Great, so in other terms there is nothing I can do and changing the DV would be a waste of time? Should I even bother inspecting it?

[Alex1188]

Honestly your options are limited...

I would say get in touch with Driver Motorsports and see if they can custom tune your car, especially since you live in florida which i just noticed!!AWESOME, they are looking for beta guys for the B8 A4, i bet they could get this issue solved and would love to help you, seeing how you have a completely built motor. DO IT!

http://www.drivermotorsport.com/home.html

[Alex1188]

Great, so in other terms there is nothing I can do and changing the DV would be a waste of time? Should I even bother inspecting it?

You could inspect it for piece of mind, but more than likely i bet its the tuning. Tuning is an extremely sensitive thing on these newer cars...

[ajehoti]

Honestly your options are limited...

I would say get in touch with Driver Motorsports and see if they can custom tune your car, especially since you live in florida which i just noticed!!AWESOME, they are looking for beta guys for the B8 A4, i bet they could get this issue solved and would love to help you, seeing how you have a completely built motor. DO IT!

http://www.drivermotorsport.com/home.html

Stop giving me butterflies you whore lol, I will give them a call

[Slick_B8]

Wtf, he sold the car??? I was waiting for updates too lol

[ajehoti]

Wtf, he sold the car??? I was waiting for updates too lol

Do these guys at Driver Motorsport have a phone number lol

[Alex1188]

Do these guys at Driver Motorsport have a phone number lol

Im sure they do, but i know they try to do alot of stuff through email, i know when i emailed them about tuning my car they got back to me pretty fast, and im sure if you said you lived in the area they would probably give there number to you.

email them at
[email protected]

[Stuck'ite]

I have "part throttle flutter" and saw this and had a quick question. I too have a K04, no head work. My "part throttle flutter" is get on the gas, and partially lift off.....say go 75% throttle or more, then back off after boost has built to say 20-40% throttle and sometimes I hear the DV flutter when I lift. This is NOT what you guy are talking about right? You are talking about say 50% throttle, accelerating an hearing flutter WITHOUT lift off the gas at all....meaning that the head porting is letting more air in part throttle than the ECU think should be possible, so the ECU "flutters" the DV to bleed it off...correct?