[Game]

Hey guys, recently installed my catless downpipes and the car doesn't seem to be idling as smooth. The RPM's don't just much however I hear a rumbling/knocking sound. The car runs and feels pretty strong. Only codes I have gotten are the usual catless dp's and after pull 4, I got the fuel pump plausibility code (2AAF).

N54 with 100k miles, turbos replaced at 45k

Mods
JB4 Map5
VRSF catless DP's
BMS DCI
VRSF CP w/ Turbsmart BOV
Shell 93 gas

Pull 2 -- (DCT off)
http://www.datazap.me/u/game/pull-2-...log=0&data=1-4

Pull 3 -- (DCT on, first pull after buying gas, had to stop short)
http://www.datazap.me/u/game/pull-3-...log=0&data=1-4

Pull 4 -- (DCT off, second pull after buying gas)
http://www.datazap.me/u/game/pull-4-...log=0&data=1-4


I recorded the rumbling I was referring too. This rumble only occurs during idle. (video was recorded day before)

Pull 4 I seem to have hit the least amount of boost. I assume map 5 fluctuates between each pull depending on conditions? Any comments/opinions would be greatly appreciated. Thank you.

[Game]

Also, if a backend flash could resolve this issue and make the car run better, I'd be all for it. Reading up on this option now.

[musc]

The rattle is likely from the right downpipe hitting the subframe/heatshield. This is pretty common as is a tight fit. Just need to loosen the v clamps and rotate them slightly.

[Game]

Originally Posted by musc

The rattle is likely from the right downpipe hitting the subframe/heatshield. This is pretty common as is a tight fit. Just need to loosen the v clamps and rotate them slightly.

Thank you, that's a great suggestion.

[Jeff@TopGearSolutions]

Originally Posted by musc

The rattle is likely from the right downpipe hitting the subframe/heatshield. This is pretty common as is a tight fit. Just need to loosen the v clamps and rotate them slightly.

I'm thinking the same thing. The tune or need for back end flash is not the issue.

You can also get a little more room by adjusting the mid pipes to pull the downpipes away from the sub frame.

[Antetokounmpo]

Just looked at your first run and you're running pretty lean down low. Can you post what your user adjustment tab looks like? It shouldn't be so lean. Also update your user interface to 30.

[Antetokounmpo]

Also set "6cyl timing" to 4 if you have an 07 or early 08 or set it to 5 if you have a mid 2008 or newer build. That way we can see timing on every cylinder. Update to newest interface first though. Try a map 2 log also.

[Mike@N54Tuning.com]

If you here clanking or rattling sounds its probably from the downpipes either hitting each other or the subframe or both. Need to go back in and adjust them.

Mike

[Agent11br]

Originally Posted by musc

The rattle is likely from the right downpipe hitting the subframe/heatshield. This is pretty common as is a tight fit. Just need to loosen the v clamps and rotate them slightly.

Had this EXACT same problem, also only at idle, a few weeks back when I had my VRSF's installed. Rear turbo DP (pass side). Had to be turned slightly. Jeff's suggestion of using the midpipes is a good one too. It was heavenly after being resolved.

[Game]

Originally Posted by Heel Toe

Just looked at your first run and you're running pretty lean down low. Can you post what your user adjustment tab looks like? It shouldn't be so lean. Also update your user interface to 30.

Originally Posted by Heel Toe

Also set "6cyl timing" to 4 if you have an 07 or early 08 or set it to 5 if you have a mid 2008 or newer build. That way we can see timing on every cylinder. Update to newest interface first though. Try a map 2 log also.

Thank you, doing all the updates now. Should my N20 TMap be set to 15?
I have now set all my duty bias and 3rd gear boost limit to 0. Going to upload the new firmware in a few minutes.

Here's a picture of my previous settings:

[jgoens]

I'm still new with my jb4 but how are you not above 17 in boost? You have more mods than me yet I consistently 17.3. Doesn't the addition of DP allow higher boost?

[Game]

Originally Posted by Agent11br

Had this EXACT same problem, also only at idle, a few weeks back when I had my VRSF's installed. Rear turbo DP (pass side). Had to be turned slightly. Jeff's suggestion of using the midpipes is a good one too. It was heavenly after being resolved.

Originally Posted by Mike@N54Tuning.com

If you here clanking or rattling sounds its probably from the downpipes either hitting each other or the subframe or both. Need to go back in and adjust them.

Mike

Originally Posted by Jeff@TopGearSolutions

I'm thinking the same thing. The tune or need for back end flash is not the issue.

You can also get a little more room by adjusting the mid pipes to pull the downpipes away from the sub frame.

Awesome, very relieved to hear this. Thanks guys.

[Game]

Originally Posted by jgoens

I'm still new with my jb4 but how are you not above 17 in boost? You have more mods than me yet I consistently 17.3. Doesn't the addition of DP allow higher boost?

My guess is that either my map 5 read the conditions and didn't think they were appropriate for 17psi OR my lack of updating the JB4 has restricted me.

I'll likely find out tonight after my updates.


edit - Also, I see that you're an N55. Not sure how much boost you guys normally run, but I'm sure it's different.

[jgoens]

I'm interested in seeing if the firmware update makes a difference

[Game]

Just updated my JB4 for the first time all I can say is WOW.

It feels like a new car. I can feel boost at much lower RPM, the car feels stronger all around, my BOV is way more responsive, and possibly most importantly my horrid wastegate rattle is almost completely gone!

Haven't played with the new menu 11 just yet, but will do so over the weekend.

[jgoens]

Originally Posted by Game

Just updated my JB4 for the first time all I can say is WOW.

It feels like a new car. I can feel boost at much lower RPM, the car feels stronger all around, my BOV is way more responsive, and possibly most importantly my horrid wastegate rattle is almost completely gone!

Haven't played with the new menu 11 just yet, but will do so over the weekend.

What exactly did you update to, ISO?

[Game]

Originally Posted by jgoens

What exactly did you update to, ISO?

No, I just never did a firmware upgrade in the almost 2 years I've had JB4. So all of the small updates rolled into today made a huge difference.

[Antetokounmpo]

Glad to hear game. Did you set all duty bias to zero in the user interface?

[Game]

Originally Posted by Heel Toe

Glad to hear game. Did you set all duty bias to zero in the user interface?

Yes, as well as max boost 3rd to 0. Thank you.

[Blaster400]

Now get an FMIC, fill up with race gas, switch to map 7 and hang on.

[Game]

Originally Posted by Blaster400

Now get an FMIC, fill up with race gas, switch to map 7 and hang on.

haha not a bad suggestion Tim, there's a gas station less than 10 minutes away that sells it (as well as E85).

[Game]

Originally Posted by Agent11br

Had this EXACT same problem, also only at idle, a few weeks back when I had my VRSF's installed. Rear turbo DP (pass side). Had to be turned slightly. Jeff's suggestion of using the midpipes is a good one too. It was heavenly after being resolved.

This turned out to be the issue. The mechanic turned it slightly and it made a world of difference. No more trembling seat/shift knob. At idle the car barely feels like it's on!