Performance issue

[Xitro]

Hi guys,

I've been haunted by performance issues quite some years now. After my chiptune to 210 hp it ran great. Until it someday just didn't want to pull as much as it did before.
I've tested my car on a bench again and it only gave 155 hp. Went back to my original tuner, where it gave 210 hp on a bench again. It's an on/off issue, sometimes it pulls great, but mostly not.
My garage/tuner don't know or don't see the issue. So I hope you guys can help me out.

Mods on my car before the tune/problems:

• Forge SPLT-R
• K&N drop-in filter

Mods that I did after the problem occured (to try to solve it):

• CAI with Injen filter
• FMIC (CXRacing)

Mods on my car now (20-11-2016):

• K&N drop-in filter with stock airbox
• FMIC (CXRacing)
• Audi 710N Diverter Valve

Symptoms:

• Since the issue I hear a lot of sucking or blowing of air noise. (Does not occur anymore after stock airbox.)
• Shortly I start hearing a ticking/rattle from the intake manifold under full load.
• Sometimes it pulls great, but mostly when I try to pull it takes forever to get to 60mph.
• Since the problem it feels that I only have good acceleration after 3,5K RPM.
• According to my tuner I have boost at 3K RPM which is quite late according to them.

Errors in VCDS (have reset them every time/keep coming back):
27-08-2015:

• 16683 - Boost Pressure Regulation - P0299 - 002 - Control Range Not Reached

23-10-2015:

• 17535 - Fuel Trim: Bank 1 (Mult) - P1127 - 002 - System too Rich - Intermittent
• 16825 - EVAP Emission Control Sys - P0441 - 002 - Incorrect Flow - Intermittent

29-04-2016:

• 17535 - Fuel Trim: Bank 1 (Mult) - P1127 - 002 - System too Rich - Intermittent
• 16683 - Boost Pressure Regulation - P0299 - 002 - Control Range Not Reached
• 17700 - Map Controlled Engine Cooling Thermostat (F265) - P1292 - 004 - Open Circuit - Intermittent

08-11-2016:

• 16683 - Boost Pressure Regulation - P0299 - 002 - Control Range Not Reached
• 16825 - EVAP Emission Control Sys - P0441 - 002 - Incorrect Flow - Intermittent
• 17700 - Map Controlled Engine Cooling Thermostat (F265) - P1292 - 004 - Open Circuit - Intermittent

I have a couple of logs available as well if you would like to check it out. This is one of my runs from a couple of days ago:
https://www.dropbox.com/s/3bi2uajzf0...0-115.CSV?dl=0

Hope you guys can help me out, thanks in advanced!

[texasboy21]

Have you performed a boost leak test?

155whp sounds about right for a stock turbo with a chip. 200+ whp isnt achievable with the stock turbo unless youre running high octane gas/E85 and/or an aggressive tune.

http://wiki.ross-tech.com/wiki/index...3/P0299/000665

[5ktq]

Boost leak? Check every hose between the turbo and throttle, and every hose that touches the intake manifold. Also if your dv is bad

[Human Garbage]

Boost leak most likely with that P0299 code. Rattling under full load could be a loose wastegate too. Pressure test and check the wastegate tension...

[Charles.waite]

His DV isn't a DV. Its a blowoff valve. and thats part of the problem. You know how much boost you're making? My guess is a bad boostleak. Check your SJP and all those vacuum lines and PCV stuff around the intake.

[rocket1420]

His DV isn't a DV. Its a blowoff valve. and thats part of the problem. You know how much boost you're making? My guess is a bad boostleak. Check your SJP and all those vacuum lines and PCV stuff around the intake.

And put the stock airbox back in. Hot air intakes hurt your performance.

[Xitro]

Have you performed a boost leak test?

155whp sounds about right for a stock turbo with a chip. 200+ whp isnt achievable with the stock turbo unless youre running high octane gas/E85 and/or an aggressive tune.

http://wiki.ross-tech.com/wiki/index...3/P0299/000665

I meant hp not whp, got lost in translation.

Boost leak test has already be done by my garage doing a smoke test, but nothing came out of it.

So things to check are my wastegate actuator, my SJP, PCV and vacuum lines.

And put the stock airbox back in. Hot air intakes hurt your performance.

Already had planned to put my stock airbox back in this weekend.

His DV isn't a DV. Its a blowoff valve. and thats part of the problem. You know how much boost you're making? My guess is a bad boostleak. Check your SJP and all those vacuum lines and PCV stuff around the intake.

My BOV/DV has already been switched out to the stock Audi DV, this didn't solve the problem, so I changed it back. Here is a log of a run of a couple of days ago, not sure what my boost is:

https://www.dropbox.com/s/3bi2uajzf0...0-115.CSV?dl=0

Thanks for the reactions so far!

[Xitro]

Put back my stock airbox this weekend. The engine is running a lot quieter and steady. It has 6 g/s more max, so a little bit more horsepower.
But I think I have my DV/BOV way too tight, not really blowing off. I think I always heard it blow-off through my CAI pipe. Need to adjust the Forge SPLT-R, but not entirely sure how much clicks it needs.

But it's not as it used to be, I need to check the actuator of my wastegate. What is the best way to check this?
Also wanted to check the SJP and PCV valves, but where are these located, so many different information on the internet. And how can I see if these are faulty or not?

[Charles.waite]

A blowoff bale dumps excess boost to atmosphere. A diverter valve dumps the air back into the intake, just past the MAF. The ECU is counting on that air staying in the system and having it dump out of the system will cause the fuel trims to be off and it will run worse as a result.

A Forge Splitter does partial recirculation and partial blowoff and the only reason for the blowoff in these applications is if you want that fast and furious noise.

Personally I would use a factory 710N valve (and did so for years on an apt stage 1+ tune) as they react more quickly, require no maintenance, and are more than capable of handling elevated boost pressures.

I'm not saying the Splitter is the cause of your issues, but it's not helping...

[rocket1420]

Put back my stock airbox this weekend. The engine is running a lot quieter and steady. It has 6 g/s more max, so a little bit more horsepower.
But I think I have my DV/BOV way too tight, not really blowing off. I think I always heard it blow-off through my CAI pipe. Need to adjust the Forge SPLT-R, but not entirely sure how much clicks it needs.

But it's not as it used to be, I need to check the actuator of my wastegate. What is the best way to check this?
Also wanted to check the SJP and PCV valves, but where are these located, so many different information on the internet. And how can I see if these are faulty or not?

I know there's info on here about checking the wastegate, probably from Old Guy or Diagnosticator. I can't remember off the top of my head.

The PCV valve is located underneath the intake manifold. Locate your oil filter. In top of that housing is a hose. Follow it up and back toward the T. The valve is in that T, pointed away from the engine.

Skip ahead to around 5:30: https://youtu.be/5Kt5ubcQaK0

[Xitro]

A blowoff bale dumps excess boost to atmosphere. A diverter valve dumps the air back into the intake, just past the MAF. The ECU is counting on that air staying in the system and having it dump out of the system will cause the fuel trims to be off and it will run worse as a result.

A Forge Splitter does partial recirculation and partial blowoff and the only reason for the blowoff in these applications is if you want that fast and furious noise.

Personally I would use a factory 710N valve (and did so for years on an apt stage 1+ tune) as they react more quickly, require no maintenance, and are more than capable of handling elevated boost pressures.

I'm not saying the Splitter is the cause of your issues, but it's not helping...

Performance > sounds: So I'll try to get a 710N valve somewhere. I read a couple of things about installing it reverse? I've got no idea why you would do that. Do you guys have any idea what's best for my car?

EDIT: I just ordered a 710N valve in the UK, so should be here (The Netherlands) on friday/saturday. Will install it this weekend.

[hightime80]

A bit off topic but by reading yours and other Eupropeans' post here in AZ I m amazed how proficient Europeans are in English. Where as here in the states not only hardly anyone is bilingual. Americans aren't even proficient in their own native tongue. It boggles my mind when people say "breaks" for "brakes" or "there" for "their". Kudos for your educational infrastructure because ours is in serious need of a revamp!

[Xitro]

A bit off topic but by reading yours and other Eupropeans' post here in AZ I m amazed how proficient Europeans are in English. Where as here in the states not only hardly anyone is bilingual. Americans aren't even proficient in their own native tongue. It boggles my mind when people say "breaks" for "brakes" or "there" for "their". Kudos for your educational infrastructure because ours is in serious need of a revamp!

Thank you for your compliment. Since the beginning (when I was quite young) of the internet I spend alot of time there. Since almost everything was English, I've taught myself English and didn't learn alot from my education. My English tests at school were always quite easy for me, without learning from my books. I can even get annoyed by people from the US or UK that do not know the difference between 'were', 'where' and 'we're'.

[Xitro]

I know there's info on here about checking the wastegate, probably from Old Guy or Diagnosticator. I can't remember off the top of my head.

The PCV valve is located underneath the intake manifold. Locate your oil filter. In top of that housing is a hose. Follow it up and back toward the T. The valve is in that T, pointed away from the engine.

Skip ahead to around 5:30: https://youtu.be/5Kt5ubcQaK0

Thank you for your reaction. I will try and look up the explanation from Old Guy or Diagnosticator. I currently do not have the plastic cover on the bottom of my car, so it's quite easy to give a look at my wastegate actuator.

Removing the intake manifold takes alot of work, I think I'll leave this one up for my garage.

[Charles.waite]

Performance > sounds: So I'll try to get a 710N valve somewhere. I read a couple of things about installing it reverse? I've got no idea why you would do that. Do you guys have any idea what's best for my car?

EDIT: I just ordered a 710N valve in the UK, so should be here (The Netherlands) on friday/saturday. Will install it this weekend.

I had mine reversed I think. Then I swapped it back to normal orientation after a year (when I reinstalled my n249 and stopped running the DV off manifold pressure). I noticed no difference.

[rocket1420]

Thank you for your reaction. I will try and look up the explanation from Old Guy or Diagnosticator. I currently do not have the plastic cover on the bottom of my car, so it's quite easy to give a look at my wastegate actuator.

Removing the intake manifold takes alot of work, I think I'll leave this one up for my garage.

Actually it's quite easy.

Take the screw out of the coolant reservoir (Phillips screw, P2). Lift reservoir out (tilt it up and forward to release the back). Remove electrical connector from the bottom. Carefully set the tank aside.

Take the hose clamp off the throttle body hose. Remove hose. Remove the two electrical connections on the throttle body. Unscrew throttle body (4 5mm hex bolts). Set throttle body aside.

Remove the throttle body support. It's the bar attached with two 6mm hex bolts, one at the intake manifold, just under where the throttle body was, and the other is at the other end of the bar, I believe attached to the engine block.

This should give you enough room to check the valve. Any further disassembly (taking off the intake manifold) requires draining some of the coolant.

When you remove the hose that holds the pcv valve, be careful (much more careful than the local shop will be). The hose that connects to the top of the oil filter housing is likely to be extremely brittle. In fact, it's good preventive maintenance to replace that part. While you're in there, it wouldn't hurt to remove the alternator and change the thermostat as well, as those are known to fail (ask me how I know.) That would require draining the coolant, of course.

[rocket1420]

A bit off topic but by reading yours and other Eupropeans' post here in AZ I m amazed how proficient Europeans are in English. Where as here in the states not only hardly anyone is bilingual. Americans aren't even proficient in their own native tongue. It boggles my mind when people say "breaks" for "brakes" or "there" for "their". Kudos for your educational infrastructure because ours is in serious need of a revamp!

Don't even get me started about "could of," "would of," "intensive purposes," etc.

[Charles.waite]

Don't even get me started about "could of," "would of," "intensive purposes," etc.

Haha. I swear they must have stopped teaching English in school staring in the naughts. Kids these days...*shakes cane at clouds*

[Seerlah]

Have

But on the internets I am guilty of this many times too, though I try to correct my grammar and misspellings most times.

Did I mention...high school drop out added to a stereotype (rhetoric)?

[Xitro]

Actually it's quite easy.

Take the screw out of the coolant reservoir (Phillips screw, P2). Lift reservoir out (tilt it up and forward to release the back). Remove electrical connector from the bottom. Carefully set the tank aside.

Take the hose clamp off the throttle body hose. Remove hose. Remove the two electrical connections on the throttle body. Unscrew throttle body (4 5mm hex bolts). Set throttle body aside.

Remove the throttle body support. It's the bar attached with two 6mm hex bolts, one at the intake manifold, just under where the throttle body was, and the other is at the other end of the bar, I believe attached to the engine block.

This should give you enough room to check the valve. Any further disassembly (taking off the intake manifold) requires draining some of the coolant.

When you remove the hose that holds the pcv valve, be careful (much more careful than the local shop will be). The hose that connects to the top of the oil filter housing is likely to be extremely brittle. In fact, it's good preventive maintenance to replace that part. While you're in there, it wouldn't hurt to remove the alternator and change the thermostat as well, as those are known to fail (ask me how I know.) That would require draining the coolant, of course.

Thanks for the explanation. Sounds like alot of work, I'm not really familiar around my engine. I know exactly how my intake works and is build, changing parts there is easy for me. But not for other things, so every step I take requires alot of 'googling' with images to know what you're talking about. :) Mostly I manage to fix things, but it's my daily driver so I really need to plan these reparations in the weekends with the parts already laying around.

About the thermostat, is mine not already failing? I've seen this error twice now this year: 17700 - Map Controlled Engine Cooling Thermostat (F265) - P1292 - 004 - Open Circuit - Intermittent.
I don't have any issues with cold-starting. And my car is getting warm in the inside as well, without any problems.

EDIT: Now that I think of it, when my car is stationairy I hear a lot of rattling coming from that location. Also with full throttle I hear a small rattle noise, also coming from under my intake manifold.
Can this be caused by a defective thermostat?

[Xitro]

Any other things I can (un)do for better performance which do not cost alot? Could just do that as well, while I'm busy.

[rocket1420]

Thanks for the explanation. Sounds like alot of work, I'm not really familiar around my engine. I know exactly how my intake works and is build, changing parts there is easy for me. But not for other things, so every step I take requires alot of 'googling' with images to know what you're talking about. :) Mostly I manage to fix things, but it's my daily driver so I really need to plan these reparations in the weekends with the parts already laying around.

I'm a little confused. If you installed a FMIC, then you should know exactly where these parts are. The pipe on the driver's side of the FMIC should go straight (more or less, I know it's bent) into the throttle body, which is attached to the intake manifold. The alternator is pretty much directly under the intake manifold, although slightly forward. It's held in by 4 5mm hex bolts (maybe 6mm, can't remember). You will have to remove the serpentine belt. Get a 17mm open end wrench and put it on the tab that sticks out on the tensioner. Push your wrench towards the passenger side. Remove belt. Once you have the alternator out (it has an electrical connection as well), the thermostat is right behind it. Good luck removing it. The J plug is right there, and should be replaced as well. It plugs a hole in the block adjacent to the thermostat. If you can't find a pic, lmk. Directly behind that is the oil filter housing. On top of it is a hose that's likely ready to break. Replace some of those PCV hoses with this kit. Since I told you that one of the hoses in that kit goes on top of the oil filter housing, the rest should be obvious with this thread.

About the thermostat, is mine not already failing? I've seen this error twice now this year: 17700 - Map Controlled Engine Cooling Thermostat (F265) - P1292 - 004 - Open Circuit - Intermittent.
I don't have any issues with cold-starting. And my car is getting warm in the inside as well, without any problems.

EDIT: Now that I think of it, when my car is stationairy I hear a lot of rattling coming from that location. Also with full throttle I hear a small rattle noise, also coming from under my intake manifold.
Can this be caused by a defective thermostat?

Possibly. Or the hose on top of the oil filter housing has broken off and is rattling around. How many miles are on the current thermostat? Unless it's been replaced in the last couple of years, I would change it. Not necessarily to fix anything related to your problem, but as preventive maintenance.

Any other things I can (un)do for better performance which do not cost alot? Could just do that as well, while I'm busy.

Well I had an answer for this, and then I lost it. Stupid computer. Simply, the answer is no. You're not replacing anything that has a "performance" version.

Have you checked for boost leaks? There's a DIY on a4mods. Also, what tune do you have? The system is running rich, which can only be caused by two things: too much gas, or not enough air.

[Xitro]

I'm a little confused. If you installed a FMIC, then you should know exactly where these parts are. The pipe on the driver's side of the FMIC should go straight (more or less, I know it's bent) into the throttle body, which is attached to the intake manifold. The alternator is pretty much directly under the intake manifold, although slightly forward. It's held in by 4 5mm hex bolts (maybe 6mm, can't remember). You will have to remove the serpentine belt. Get a 17mm open end wrench and put it on the tab that sticks out on the tensioner. Push your wrench towards the passenger side. Remove belt. Once you have the alternator out (it has an electrical connection as well), the thermostat is right behind it. Good luck removing it. The J plug is right there, and should be replaced as well. It plugs a hole in the block adjacent to the thermostat. If you can't find a pic, lmk. Directly behind that is the oil filter housing. On top of it is a hose that's likely ready to break. Replace some of those PCV hoses with this kit. Since I told you that one of the hoses in that kit goes on top of the oil filter housing, the rest should be obvious with this thread.


Possibly. Or the hose on top of the oil filter housing has broken off and is rattling around. How many miles are on the current thermostat? Unless it's been replaced in the last couple of years, I would change it. Not necessarily to fix anything related to your problem, but as preventive maintenance.



Well I had an answer for this, and then I lost it. Stupid computer. Simply, the answer is no. You're not replacing anything that has a "performance" version.

Have you checked for boost leaks? There's a DIY on a4mods. Also, what tune do you have? The system is running rich, which can only be caused by two things: too much gas, or not enough air.

I installed the FMIC, don't laugh, but it took me a full week to do it. I know where my intake manifold and throttle body is, but I've never removed it. So I'm not sure what everything around it is and what's underneath.
Thanks for your information about what to replace, I'm going to look into it. I need pictures to understand. xD

I think (but I'm not sure) that my thermostat was replaced when my water pump stopped working. That's 70.000km (44.000 miles) ago.

I did not check for boost leaks, my carshop did this for me a while back. I have a Stage 1 (custom) chiptune: http://www.jdengineering.nl/1-8-20vt-150pk-163pk-180pk/. I think my Forge SPLT-R might cause my system running too rich, because it blows off 30%, which my ECU expects back into the system. I ordered a 710N which I'll put in this weekend, hope it arrives on time.

[rocket1420]

I installed the FMIC, don't laugh, but it took me a full week to do it. I know where my intake manifold and throttle body is, but I've never removed it. So I'm not sure what everything around it is and what's underneath.
Thanks for your information about what to replace, I'm going to look into it. I need pictures to understand. xD

I think (but I'm not sure) that my thermostat was replaced when my water pump stopped working. That's 70.000km (44.000 miles) ago.

I did not check for boost leaks, my carshop did this for me a while back. I have a Stage 1 (custom) chiptune: http://www.jdengineering.nl/1-8-20vt-150pk-163pk-180pk/. I think my Forge SPLT-R might cause my system running too rich, because it blows off 30%, which my ECU expects back into the system. I ordered a 710N which I'll put in this weekend, hope it arrives on time.

I wouldn't laugh at someone who starts a project and sees it through to the end.

I'm not going to lie, getting the intake manifold off can be a huge PITA, for one reason only: that black coolant hard pipe. It has four "soft" pipes going into it. You have to remove the front two. The one is easy. It snakes from the turbo across the timing belt cover to the hard pipe. That's the easy one. The other one goes straight down through the intake manifold to the thermostat. That hose is stupid difficult unless you remove the alternator. Then you have easy access to those hose clamps.

You're creeping up on a timing belt change, so either do that now or wait to change your thermostat for another 20000 to 30000 miles and do it with the timing belt job.

If I were you, I would make the boost leak tester and verify the results. You may be right that the 710N will fix your performance issues. I hope it does.

Good luck!

[Xitro]

Update: Got my stock airbox in previous weekend, since then I do not experience this symptom anymore: "Since the issue I hear a lot of sucking or blowing of air noise.".
This weekend I replaced the Forge SPLT-R for a 710N, which I picked up at Ebay. Did not have time to check out my wastegate actuator and valves under the intake manifold, the problem is that I use this car to get to work, so can only take a couple of hours in the weekends for one thing at a time.

Still experiencing slow boost. And also the strange rattle, this doesn't always occur. But when it does it only does on full throttle.

[old guy]

You may have a sticking N75 Boost Control Valve. You can clamp off the hose that connects the N75 to the wastegate and go for a spin. If you immediately get boost where you didn't before you will have eliminated boost leaks, DV and the probably the wastegate as part of the problem.

Next you should remove the clamp and log MB114 with MB115 so you can check the N75 duty cycle against the requested/actual boost.

If the N75 duty cycle and requested boost goes up but the actual boost lags considerably behind it's probably the N75 causing the problem.

If your N75 duty cycle, requested and actual boost align then the problem is with the ECM reacting to some other input and not calling for the boost in the first place which will require some additional troubleshooting.

[Xitro]

You may have a sticking N75 Boost Control Valve. You can clamp off the hose that connects the N75 to the wastegate and go for a spin. If you immediately get boost where you didn't before you will have eliminated boost leaks, DV and the probably the wastegate as part of the problem.

Next you should remove the clamp and log MB114 with MB115 so you can check the N75 duty cycle against the requested/actual boost.

If the N75 duty cycle and requested boost goes up but the actual boost lags considerably behind it's probably the N75 causing the problem.

If your N75 duty cycle, requested and actual boost align then the problem is with the ECM reacting to some other input and not calling for the boost in the first place which will require some additional troubleshooting.

Thank you. I will give this a try to see if this eliminates the boost issues.

I actually logged 115 before and am experiencing that my actual boost lags behind the requested boost, see this log: https://www.dropbox.com/s/3bi2uajzf0...0-115.CSV?dl=0
So the problem should probably be the wastegate then?

[old guy]

Not necessarily the wastegate. Your log doesn't show the N75 duty cycle. It would be good to see that along with the actual/requested boost (MB114). I suspect it is going to show a high duty cycle with slow boost onset but it would be best to see if that is actually what is happening.

A sticking/slow to respond N75 can also cause the issues you are having. That is why I recommended you try clamping off the N75 signal line to the wastegate and see what happens. Clamping the line is essentially doing the same thing that a 100% N75 duty cycle does. It dumps the pressure back into the TIP and allows the wastegate to stay closed.

[Xitro]

Not necessarily the wastegate. Your log doesn't show the N75 duty cycle. It would be good to see that along with the actual/requested boost (MB114). I suspect it is going to show a high duty cycle with slow boost onset but it would be best to see if that is actually what is happening.

A sticking/slow to respond N75 can also cause the issues you are having. That is why I recommended you try clamping off the N75 signal line to the wastegate and see what happens. Clamping the line is essentially doing the same thing that a 100% N75 duty cycle does. It dumps the pressure back into the TIP and allows the wastegate to stay closed.

Is this the line that you are talking about?

That should be very easily accessible from above.
Now I only got to find a way to clamp this off.

[Audi body]

Do you have a boost gauge?

[old guy]

Is this the line that you are talking about?
That should be very easily accessible from above.
Now I only got to find a way to clamp this off.

You can either clamp the hose from the high pressure port on the turbo to the N75 or the hose from the N75 to the wastegate actuator. Whichever is easier to access.



All you need to clamp it off is a simple hose pincher.

[Xitro]

Hereby an update: I haven't been able to clamp of that hose yet. It's just too cold outside, so will do that somewhere in the new year.
My car seems to drive much better now. The only code I got after more than a month is the following one:

16825 - EVAP Emission Control Sys - P0441 - 002 - Incorrect Flow - Intermittent

Any ideas about this? Is it something to worry about?

[old guy]

A P0441will not cause any performance issues. It may be a sticking or defective N80 evap control valve.