[WhiteFury]

So I have the JB4 stage 2 and did a run with the 14.5 psi map here, I got a half engine light that said reduced output for like 3 seconds after the 3rd gear pull. The light went out after that and no SES or check engine light codes stored??

My AFR is like 14 or 15 should it not be like 12?? I am only hitting 8 psi of boost I dont get it.

What is going on with the this?

Here is the csv log from the jb4. its zipped. so just unzip.

Thanks for the help guys.


EDIT: On a hunch I did a Map #1 run. Although it doesnt feel that strong down low it feels stronger up top. I did 2 second gear pulls 3000-5000 rpms NO engine light. It also peaked right at 9-10psin map #1 but map #2 is peaking around 7-8psi. So map #1 is only 1-2 psi below target yet map #2 is 6-7psi below.

Any thoughts?


I also hear this tin can echo sound while holding the pedal around 60% throttle. I can hear the turbo swoosh and spool but I can hear this weird echo. Wastegate set to 80. When I set i to 50 it sorta stopped.

[WhiteFury]

So I went ahead and just checked the Charge pipe and fastened it down. Cleared adaptations as well.

I did some more runs and the engine light didnt come on. I did like 7 pulls in 3rd. So I guess thats good.

I forgot to add that I have second o2 sensor in a double defouler. I feel my runs look lean.

I also noticed that in stock map run, I am boosted at the target or higher but in map1 or 2 there is much less.


The other day I was getting 2D34 and 2D1B codes. The jb4 said something about the accelerator position input one. The other was secondary o2 sensor deviates from primary too much. I also had a lean o2 secondary code. Which John @ Burger said was the 2D1B. However that code was listed as the accelerator input position #1.

Here are some more runs


Picture 1 = Map#1
Picture #2 = Map #2
Picture #3 = Map #2
Picture #4 = Stock Tune w/CAN active Map#4

[WhiteFury]

I switched over to the ISO setup. Much smoother. Still cant break 10-10.5psi tho.

Here is a map #1 log.

[Markus8291]

did you just install it or have you had it and this is something that just started happening? Also, why don't you just run map 5 and let it do it's thing? I tend to trust that more...not sure why. I've never had my jb4 in map 2. Briefly map 1 once and since then map 5 every day. After adaptation it hits about 18psi on map 5.

[WhiteFury]

Originally Posted by Markus8291

did you just install it or have you had it and this is something that just started happening? Also, why don't you just run map 5 and let it do it's thing? I tend to trust that more...not sure why. I've never had my jb4 in map 2. Briefly map 1 once and since then map 5 every day. After adaptation it hits about 18psi on map 5.

Was doing it before and then I went ISO to help diagnose it better. Jon and terry suggested it.

Terry thinks I need to look for a boost leak or Wastegate hardware issue.

I wish I could hit 16psi no matter what I do it won't go above 10psi.

Stock - 7-8 psi
Map 1 10 psi
Map 2 10 psi

I just can't build anymore boost. Will a catless downpipe make more or less boost due to more flow?

[Markus8291]

Originally Posted by WhiteFury

Was doing it before and then I went ISO to help diagnose it better. Jon and terry suggested it.

Terry thinks I need to look for a boost leak or Wastegate hardware issue.

I wish I could hit 16psi no matter what I do it won't go above 10psi.

Stock - 7-8 psi
Map 1 10 psi
Map 2 10 psi

I just can't build anymore boost. Will a catless downpipe make more or less boost due to more flow?

I definitely got more boost once I got my downpipe on. Before the Dp is was hitting about 14psi.

[WhiteFury]

Where do you think my issue lies?

[FriedPiston]

How many miles do you have on the N55? and how many miles with the tune?

Besides the charge pipe, have you checked all end points (turbo, dp, IC) for leaks? How do the spark plugs look like?

[WhiteFury]

Originally Posted by narstune

How many miles do you have on the N55? and how many miles with the tune?

Besides the charge pipe, have you checked all end points (turbo, dp, IC) for leaks? How do the spark plugs look like?

plugs, coils, injectors all changed @ 64k. 68k on the car now. I havent checked anything else. However the feels strong down low. It may have been like this since the tune got installed. Due to my problem with my intake manifold removal months back.

The downpipe setup is kinda weird it just lines up with the turbo and a band clamp holds it, is it possible that is leaking or is it a leak after the turbo before the engine?

[FriedPiston]

Hmm, reading through your mod list, I'll make the assumption that you don't have an upgraded intercooler unit. If this is the case, the up-pipe found on the cold side of the stock IC is known to cracking on the N55. You may want to check that as well.

Easiest way to trace any leak is to have a shop run a smoke test -

If everything checks out then perhaps your wastegate actuator maybe malfunctioning. I'd recommend posting this issue on n54tech and ask for Terry's expert advice.

[WhiteFury]

Originally Posted by narstune

Hmm, reading through your mod list, I'll make the assumption that you don't have an upgraded intercooler unit. If this is the case, the up-pipe found on the cold side of the stock IC is known to cracking on the N55. You may want to check that as well.

Easiest way to trace any leak is to have a shop run a smoke test -

If everything checks out then perhaps your wastegate actuator maybe malfunctioning. I'd recommend posting this issue on n54tech and ask for Terry's expert advice.

Link doesn't work. I cant see what you posted. Do you mean the pipe that connects to the Charge pipe? The intercooler pipe on the driver side?

Also if my wastegate is malfunctioning this is the part I need right?

11657601058

[WhiteFury]

Issue has been resolved, just realized that my intercooler piping on the hot side had some oil residue around the O-ring so I wiped it and made it squeaky clean so that it would seal properly.

Also took my secondary oxygen sensor out of the Defouler and put it right into the catless downpipe.

Also the hose that connects to the valve cover and goes to the boost control solenoid is slightly pancake flat where it bends.

I am now seeing 15 psi. Issue seems to be gone. Just need to figure out if I should replace the hose or not.

[WhiteFury]

I think I found the issues causing this. The vacuum line on passenger side valve cover that is connected to the boost control solenoid has a bend and it was flat there slightly.

Also a very slight leak on the charge pipe. I also had o2 sensor in a defouler.

I'm back to 14-15psi. Just gotta get the last bit of the leak.