Still Low Boost 13psi...(apr)

[smartyin]

i got apr chip for a year it was peak at 18psi, recently i just found that my car just hit 13psi to 14psi, do you guys know what is the problem,,,i have change my PCV AND FORGE DV....BUT THE IT STILL ONLY HIT 13 PSI OR 14 PSI PEAK.....

[Keith@APR]

Did you check the rear pcv too?

[smartyin]

REAR PCV??i don't know this thing...WHERE IS IT?

[smartyin]

HI THERE

i found there have 2 type of rear PCV for A4 2.0t on ecstuning web site.
one is "Genuine Volkswagen / Audi - Breather Tube ES#8583" which cost $50.26

another one is also call "Genuine Volkswagen / Audi - Breather Tube ES#11560" but cost $57.04.
my car is runing 06F-129-101-F FRONT PCV, WHICH rear pcv IS SUITABLE TO ME??
many thanks!

[p1nk50ck]

what is with your use of capital letters?

[smartyin]

Did you check the rear pcv too?

i checked it today,,,it is very clean around the rear pcv and DV,,,no oil leaking..

[Keith@APR]

i checked it today,,,it is very clean around the rear pcv and DV,,,no oil leaking..

I guess that will about do it then for internet diagnosis. I can offer one more suggestion to help you determine for your own satisfaction if its a software or hardware issue.

You can log block 115 in vagcom under engine, measuring blocks to see what your requested boost pressure is. ECU software doesn't change over time so I am confident its not software related.

Unfortunately I don't have any other suggestions as you've covered the usual suspects. It sounds to me like you are going to have to visit a performance oriented service center that will help you fix the leak if the Audi dealership is unsuccessful.

[smartyin]

I guess that will about do it then for internet diagnosis. I can offer one more suggestion to help you determine for your own satisfaction if its a software or hardware issue.

You can log block 115 in vagcom under engine, measuring blocks to see what your requested boost pressure is. ECU software doesn't change over time so I am confident its not software related.

Unfortunately I don't have any other suggestions as you've covered the usual suspects. It sounds to me like you are going to have to visit a performance oriented service center that will help you fix the leak if the Audi dealership is unsuccessful.

Hi keith

thanks for advise anyway, but i don't really know where is the rear pcv i just change to "F" version PCV like the photo below.



Also, as i just installed apr fuel pump. do i need to upgarde my program?

[Keith@APR]

Hi keith

thanks for advise anyway, but i don't really know where is the rear pcv i just change to "F" version PCV like the photo below.



Also, as i just installed apr fuel pump. do i need to upgarde my program?

Ah sorry, I thought you posted you had checked the rear.



Its the check valve in the pic titled Exhaust Turbocharged Gas Outlet.

[nick71692]

i peak at 14psi but i have an mtm chip, which i think does not have the same amount of boost, it is only like 245 horse and 265 tq.

[kurupt_hawaiian]

Yeah, i got a custom chip from a tuner shop in germany, but i only get about 15-16 psi of constant boost.

[Sal_B7]

did you recently take it to a dealer for any work? If you did they might have reseted your ecu and therefore erased the APR software you had. If so you will have to get back to your dealer where you got chipped at and get reflashed.

[NothingBUTasian]

what's apr 93 octane supposed to be boosting?

edit: sorry if that's a newp question, i'm just lazy to search because it'll return an insane amount of results. I'm installing a boost gauge this weekend and will see what I'm boosting, so I want to make sure that my apr 93 stage 2+ is boosting correctly.

Joshua

[grmntoy]

i had a similar issue with my revo. I would spike 22 psi and last saturday i saw 15-16psi for like 3 days(very cold days), and today it just went to 19psi(warmer days), im running out of fuel since i did get a full tank of gas on friday night, maybe it has to do with bad gas, or the weather. Apr or someone else chime in on this!

[Keith@APR]

what's apr 93 octane supposed to be boosting?

edit: sorry if that's a newp question, i'm just lazy to search because it'll return an insane amount of results. I'm installing a boost gauge this weekend and will see what I'm boosting, so I want to make sure that my apr 93 stage 2+ is boosting correctly.

Joshua

Motronic 9, our engine management system, is a load based system.

What that means in layman's terms is that there are very few constant or static settings inside the ecu. This means a calibrator isn't necessarily setting a target boost the ecu will always request and deliver.

The calibrator sets a range of acceptable operating parameters and then the ecu applies the best target in that range based on feedback from the various sensors on the engine.

For example, the ecu is trying to meet a requested load set by the calibrator. Let's say the load request is 100%. The ecu will then look at knock, egt's, iat's, ambient pressure and temp and other parameters of how your engine is running at this exact moment. It will then apply an air fuel ratio, timing angle and boost pressure that will best arrive at that 100% load request.

That being said, it is possible to narrow this range or even to set the ecu to a type of static operation where no matter what you will always run say, 20 psi for instance. This is how engines were calibrated to operate back in the 80's and early 90's when ecu's were extremely low tech in comparison to the great advancements in ems control and operation strategies we have today.

Some aftermarket "tuners" are frustrated by these new technologies and work very hard to turn alot of it off. This makes the calibration easier, no doubt, and is more consistent with what people are historically used to seeing. However, as with everything in life, there is a trade off when doing so. The engine will no longer be able to respond as precisely to changes in the operating conditions and can be even less powerful and more subject to running issues.

Now, why did I just type all of this?

Because some of you are inquiring what psi you should see with your APR ecu upgrade. Well, that's subjective. Given multiple datalogs and reports of the exact operating conditions we can actually use a series of mathematical calculations to arrive at exactly what boost you should be running. The ecu does this exact same process when determining the target boost pressure to meet the requested load.

Without doing the math, and although it would be fun, I'm not going to do it nor get into it, you know, the whole trade secrets dealio and all, you should be seeing anywhere from 15psi to 21psi depending on conditions.

If you have a properly running car and are seeing on the lower side of the boost pressure range, fret not. Boost does not always equal power.

You are still meeting the calibrated requested load which is the power or torque that you are making. You are just making it through other means besides boost pressure. You are still at that 100% load number you are just getting there through say, more aggressive timing as opposed to more boost.

13-14 psi is definitely a little bit low in regards to the op and I suspect he has a small boost leak somewhere.

[NothingBUTasian]

interesting...Thanks keith...if you ever come into philly...I'll buy you a beer...(for a free apr t-shirt)...lol

[grmntoy]

Hahaha thanks Keith thats a great explanation and what i was looking for.

[smartyin]

hey guy
i just want to update the satuation, i still haven't found the problem. i don't find any leak.....but i made a video which i think it is weird,....

http://www.youtube.com/watch?v=C5AozAXOONE

[NothingBUTasian]

mind does that too...you have no load so it's not going to really boost at all. I'll post a vid of my defi unit.

[gpxluke]

I have apr too, I peak at 18~20 PSI at the Octane 93 program...

[NothingBUTasian]

wow...I only peak at 19ish when I'm in 6th gear and I floor it...other than that, I am usually around 17 peak and 15 hold...then it steadily drops. Even though it was boosting 19lbs, it wasn't going anywhere because of the gear i was in.

[ringofsteel]

Check the N75 valve. If you have the 2.0t long block it is above the DV valve . I had similar issues too. I gave up on my Forge dv and went with awe. It is the heat. my forge dv after one year needed a rebuild kit. yea they dont tell you that when you wack out the money. Keith at apr told me about the N75 valve after replacing the PVC,dv,. If the you have idle issues it should be the PVC. If you have surging boost issues it could be a stuck dv or the N75. Just my two cent. I have pics if you need em.

[smartyin]

thank you for all advices upon.

i will try to change the rear Check value and The N75, see if it would work.

how dose N75 look like?

[smartyin]

anyone have the N75 part number for 2.0t fsi?

[ringofsteel]

http://edition719.com/smf/index.php/topic,103860.0.html

here is the link I posted on my car club site. Thre are pics for it. I am trying to get the part number. It is easy to install, About 45 min or so. hope it helps
here is the part number for the N75 valve 06f 906 283f

[smartyin]

http://edition719.com/smf/index.php/topic,103860.0.html

here is the link I posted on my car club site. Thre are pics for it. I am trying to get the part number. It is easy to install, About 45 min or so. hope it helps
here is the part number for the N75 valve 06f 906 283f

thank you for your informations,,,i just bought a new N75, but i found that it is very hard to open the factory hose clamps. do u have any idea to open it?

[ringofsteel]

I just used a thin flat head, and lifted up on the end. This is the longest part of the change. I used as the pics show small hose clamps. Two of the ends on the N75 are plastic. You could cut them, then get the factory clamps off. I broke one then was able to get the other. small space for an easy part. Good luck.

[smartyin]

...........just spent 2 hours to install the N75,,,,,,,it is really hard to get those clamps off.
For the boost,,,,,,,still 13psi.no change or better....shit,,,i don't know wht to do now...

[smartyin]

any suggestions?
anyone know the part number of the rear check value, maybe i just have to change it as well, see if i have any luck......thanks!

[smartyin]

hi there
i just want to update some informations that i found. to day i vagcom my car
and i found this code, dose it related to my low boost problem? and i got fault code which related to MY HIGH FLOW CAT. it showed Cat B1 IS NOT OK....<---what dose it means?and i will try to post my 115 log later...many thanks guys

[smartyin]

pump

[rams456]

i got apr chip for a year it was peak at 18psi, recently i just found that my car just hit 13psi to 14psi, do you guys know what is the problem,,,i have change my PCV AND FORGE DV....BUT THE IT STILL ONLY HIT 13 PSI OR 14 PSI PEAK.....

how long has your car been chipped?

[smartyin]

it ran with apr 93 for 25,000km and around 2 years,,,,it is 2006 car,,,,i chipped it around a year later(2007). and i am using milltek HIGH FLOW CAT,,,it has ran for 25,000km and around 2 years as well

[smartyin]

Does a bad high flow cat affect the turbo boost??what does it like if i blown the cat?

[Insane_Audi]

a high flow cat should give u more boost because there is less back pressure

[smartyin]

a high flow cat should give u more boost because there is less back pressure

but how about a bad cat?

[Insane_Audi]

i am not sure what you mean by a bad cat

the only thing that can really go wrong with a cat is the O2 sensor can give you a false reading or you can damage it, either way neither will really affect the pressure that your turbo is putting out

[BLACKa4QUAT]

well if the cat is bad it could choke up the system, thus causing your issue. i'm not sure if a worn out HFC will flow better than an OEM cat.

[Insane_Audi]

well if the cat is bad it could choke up the system, thus causing your issue. i'm not sure if a worn out HFC will flow better than an OEM cat.

how so, i did not know this

[BLACKa4QUAT]

how so, i did not know this

the metal catalyst goes bad in them, and since there's less of the material in a HFC it wears out faster. running rich can screw up a cat too, like driving with a busted coilpack.