03 ALH down on power

[Toddhess92]

So I've been in the process of building up my 03 alh with the following mods.

Southbend Stage 2 endurance
DLC1019
Stage 3 malone

Have replaced all the following with all oem
MAF
N75
Vacumn lines and one way valve (routed per diagram on the fourm via deletes)

The car seems sluggish to me to what it should be imo after all the mods too, my family has a bone stock 03 ALH golf that has more pull i feel when you get on it. The only thing that seems off to me is the car straight piped use to sit and idle with a loud turbo whine, lately upon start up it does but after you drive it and come to an idle the turbo noise is very faint. I pulled the actuator off and it moves very free no binding or anything I tested it as well and it pulls smooth. The arm on my turbo I can move freely up and down, but I can also pull it up even further (towards the hood) and it has some binding then. I reinstalled the actuator and checked and it does not start moving untill 4 and is all the way down around 18 smoothy which seems to be in spec so I'm at a lost. I have some vcds info as well. Thanks

 

[Nero Morg]

Do a hard pull in 3rd and data log maf and boost readings. Readings at idle just says it runs good at idle.

 

[Nevada_TDI]

From 2k RPM in 3rd gear up to the speed limit, MAF, actual and requested boost and N75%. This will give us an idea of what is happening, or not happening.

 

[pkhoury]

I'm having the same problems as the OP. I have a dual diaphragm clutch/Peloquin LSD, brand new Melett VNT17, Darkside custom intake, and also 2.5" straight piped. @Franko6 rebuilt my injectors and put on .230 nozzles. Like the OP, I replaced all my vacuum lines,. and I've been using the EGR vacuum solenoid, wondering if my N75 was bad or not (but I don't think so). The car is lacking a lot of power until I get over about 3000 RPM.

 

[Nevada_TDI]

If you have not already, check vacuum everywhere from driver's side to passenger side to check for loss. Or, provided you still have all the solenoids check the one the farthest from the vacuum pump, if you do not have a solid 22" or better of vacuum at the passenger side, check for bad/cracked solenoids from one side to the other. Connected to my vacuum pump is the brake canister, the vacuum bulb, the check valve and the turbo. Straight simple for the "off road

 

[Toddhess92]

So I somewhat did a run and here is what I saw

http://imgur.com/a/GQ6zdwT

 

[Toddhess92]

W;\JFriday,29,January,2021,13:58:22:02752
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 20.12.0.1 (x64) HEX-V2 CB: 0.4529.4
Data version: 20201125 DS322.1
www.Ross-Tech.com





--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 01: Engine (038 906 012 GN)

13:58:19 Group 003: Exhaust Gas Recirculation (EGR) - Switch to Basic Settings for EGR test
1491 /min Engine Speed (G28)
555.0 mg/str Air Mass Specified
525.0 mg/str Air Mass Actual
19.9 % EGR Solenoid (N18)

13:58:19 Group 011: Charge Pressure Control
1491 /min Engine Speed (G28)
1040.4 mbar Boost Specified
1091.4 mbar Boost Actual
39.0 % Charge Pressure (N75) Solenoid
Friday,29,January,2021,14:16:44:02752
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 20.12.0.1 (x64) HEX-V2 CB: 0.4529.4
Data version: 20201125 DS322.1
www.Ross-Tech.com




Address 01: Engine (038 906 012 GN)

14:16:37 Group 003: Exhaust Gas Recirculation (EGR) - Switch to Basic Settings for EGR test
1806 /min Engine Speed (G28)
640.0 mg/str Air Mass Specified
635.0 mg/str Air Mass Actual
83.3 % EGR Solenoid (N18)

14:16:37 Group 011: Charge Pressure Control
1785 /min Engine Speed (G28)
1122.0 mbar Boost Specified
1183.2 mbar Boost Actual
50.2 % Charge Pressure (N75) Solenoid

 

[Nero Morg]

Was this taken at WOT in 3rd? If it was, that air mass actual is way too low, good sign of a bad MAF sensor.

 

[Toddhess92]

Was this taken at WOT in 3rd? If it was, that air mass actual is way too low, good sign of a bad MAF sensor.

It wasn't wide open flat to the floor but I did hammer down on the throttle a few different times and it seems that was the case air mass actual less than specified. Weird thing is this is the 2nd maf I tried. The original one with 200k on it. And this brand new oem Bosch unit

 

[derek5120]

Things to check. Is your egr still hooked up and is your intake clean? Have you checked your snow screen in your airbox for debris. Checked your intake after the maf for leaks. Is your egr valve closing all the way and not hanging open.

 

[Toddhess92]

Things to check. Is your egr still hooked up and is your intake clean? Have you checked your snow screen in your airbox for debris. Checked your intake after the maf for leaks. Is your egr valve closing all the way and not hanging open.

Has a race pipe and is tuned out in the tune along with the asv. Car doesn't have a factory airbox came with a filter when I bought it, so I had replaced it with a new aem dry filter so it was new. Car has a omi as well. No known leaks past maf but I could definitely do a more through look there

 

[Nero Morg]

You didn't mention if you checked the snow screen. It's on a pipe mounted under the air box next to the fender. Prone to getting plugged up. Your maf low reading is probably why you have lower than expected power.

 

[Toddhess92]

You didn't mention if you checked the snow screen. It's on a pipe mounted under the air box next to the fender. Prone to getting plugged up. Your maf low reading is probably why you have lower than expected power.

Alright thanks for the replies. I'll check the snow screen. I just bought this MAF about a week ago brand new from kerma. Maybe it's faulty I guess? I hate to order another one but maybe I have to then

 

[turbocharged798]

I don't believe an 03 would have a snow screen, that was on the early cars only.

 

[derek5120]

My 03 Jetta had one, when I checked it at 300km it was plugged solid I think the op said he wasn’t using the original airbox anyway.

 

[Toddhess92]

My 03 Jetta had one, when I checked it at 300km it was plugged solid I think the op said he wasn’t using the original airbox anyway.

Do you think I'd be better off using the oe airbox and oe filter?

 

[derek5120]

I was just saying that because you weren’t using the factory airbox the snow screen isn’t a issue as the filter wouldn’t be drawing air through there only. Try and unplug your maf and go for a drive. The ecm will substitute a base map, see if that feels better. If it does you may have a bad maf, there is cases of people getting defective mafs. Also as a tech I run into lots of dirty maf from aftermarket filters, they are less restrictive but dirty your maf elements

 

[Nero Morg]

I don't believe an 03 would have a snow screen, that was on the early cars only.

Mine had one for sure. Left it in for a while before getting frustrated about cleaning it regularly.

 

[Toddhess92]

I was just saying that because you weren’t using the factory airbox the snow screen isn’t a issue as the filter wouldn’t be drawing air through there only. Try and unplug your maf and go for a drive. The ecm will substitute a base map, see if that feels better. If it does you may have a bad maf, there is cases of people getting defective mafs. Also as a tech I run into lots of dirty maf from aftermarket filters, they are less restrictive but dirty your maf elements

so i have a better understanding, I have been driving around with vcds on 11 and 3 observing what i can. say your going up a gradual hill 3rd or 4th and get a slight load on the motor lugging it down nothing crazy just slight. should the ecm see that and adapt fueling or is it just saying what it wants? i noticed in that sceniaro the air mass specified would be lets say 700 and actual only low 600s. is this normal due to it being lugged down some or should it correct and be the same actual and specified all the time?

 

[Nero Morg]

The engine wants to see maf actual and specified as close as possible. The reason you want to do a hard WOT pull in 3rd is because you should see the maf actual go as high as 1400 mg/st, maybe even higher, irregardless of specified. If the engine sees less air going in, it reduces fueling to maintain the smoke map.

 

[Nevada_TDI]

As mentioned above this is what you need: 3rd gear pull WOT from 2k RPM until redline. Please do not lift from the throttle, or the log will have to be redone.

 

[Nevada_TDI]

Get a log from 1500 RPM or so to the speed limit. You showed a couple of places, which is not super diagnosing. Go to Log down on the bottom left of the page and it will show an Excel file. you have to keep your foot on the floor until you stop logging.
You should see a file that looks like this: LOG-xx-xxx-xx.xl
If you don't see this at the bottom left of the page, you might be on the wrong page.

EDIT: I should have said bottom right, not left