Hesitation w/ Unitronic Stage2

[GTIpilot1]

Hesitation w/ Uni 2 (Video of possibly related issue)

SEE MY MOST RECENT POST ON PAGE 2 FOR MORE INFO.


I've been getting some pretty significant hesitation when going wot at 2800rpm and up. The car will hesitate, then surge, then hesitate again, and surge until finally accelerating normally. This has been tested with and without traction control engaged; it returns the same results.

Anyway, I was prompted by David@Unitronic to log 001-031-230 and 003-020-115.

The logs have been done in 3rd gear and begin at roughly 2800rpm (where the problems are).

Also, in the 003-020-115 log, I recorded the data toward the end at idle throttle (while the car was decelerating in neutral). It was going up and down between 1200 and 1500rpm on its own. Not sure if this is normal or not.

I thought it was caused by my Modshack intake being too close to the MAF, so I bought an Injen intake. It got better for a few weeks, and now it's back again.

These logs have been sent to Unitronic, however I'm wondering if anyone on here has had experience with these issues.

Here are the logs if you'd like to take a crack at it.
001-031-230 : http://s000.tinyupload.com/index.php?file_id=84616459949595920645

003-020-115 : http://s000.tinyupload.com/index.php?file_id=55353442532999473026

Thanks in advance to those who post up!


UPDATE: Here is the video of what it's doing now. This happens intermittently after the vehicle is driven, left in the sun for a few hours, and then driven again.

http://www.youtube.com/watch?v=2fuBsmvjqYA&feature=channel

 

[GTIpilot1]

Also, no codes with VCDS.

 

[mully]

it sounds like a failing o2 sensor. I couldn't open your data log though. Do you run an afr gauge?

 

[markwid]

Similar problem on stage 2 when I installed Carbonio intake. Reverted to stock intake w/ drop in. Hesitation at around 2700rpm gone after that.

My guess is that Mk6 MAF is finicky and sensitive to air turbulence.

Try stock intake and let us know how you go.


Sent from my iPad using Tapatalk

 

[mully]

It doesn't sound like an intake issue as 2 different intakes produced the same problem. The modshack has been tested to produce smooth airflow over the maf and keeps fueling within +/- 5%. That's really good for an aftermarket intake.

 

[GTIpilot1]

Everything was fine until my dealer ran it through the car wash. Last time this occurred, it was just after my last checkup at the dealer (and yes, they ran it through the wash) ....

perhaps leaving the car running through an automatic car wash could cause harm w/ an open filter system like Injen

 

[twistid]

Maybe they didn't seal the ecu properly ?

 

[GTIpilot1]

I watched my Uni rep do it... He seemed to have it sealed properly, but what do I know...

Although I can't rule it out, I'm hoping that's not the case.

 

[Thumper]

Everything was fine until my dealer ran it through the car wash. Last time this occurred, it was just after my last checkup at the dealer (and yes, they ran it through the wash) ....

perhaps leaving the car running through an automatic car wash could cause harm w/ an open filter system like Injen

Unless they pointed a solid stream of water through the grille aimed at the intake there's no way for that to do anything. Won't get anymore water in there than during heavy rain and highway driving.

 

[Todd@ECS]

check your injectors. mine were slightly clogged and caused a misfire when i went WOT.

 

[GTIpilot1]

No codes or misfires (or so it seems since my vagcom scan was clean) .... I'm hoping it's injectors or something straightforward just to clear up this issue.

Could it be injectors with only 5400 miles?

 

[GTIpilot1]

A local friend just had his throttle body replaced with similar (but not identical) symptoms.
Is this even a possibility?

I've also been told "bad gas" could be the culprit. However, the car hasn't had any misfires and I only run Shell V-Power or Chevron Supreme, so that seems less likely, although it's not being ruled it out.

So far, the issues seem more along the lines of a problem with fuel delivery, so right now I'm thinking I'll do some Lucas Oil to see if that alleviates it.

Other thoughts/suggestions are still much appreciated!

 

[steemax]

Put your stock airbox back on, and report back :thumbsup:

Same exact problem as yours, changed my intake/cleaned my MAF and its all smooth sailing from there. These tunes seem to be very sensitive with any intake work.

EDIT: just read you tried changing your intake. I'd still trying putting the stock back on.

 

[ns01gti]

Not sure if it's the case here, but I've seen a few cases where the Unitronic tunes seem a bit sensitive to running Carbonio intakes. As suggested, either try the stock intake or take the enclosure off the carbonio.

Had a look at your logs as well. Nothing really stands out in there. Have you tried going to the Unitronic website and opening a ticket with tech support?

 

[GTIpilot1]

Not sure if it's the case here, but I've seen a few cases where the Unitronic tunes seem a bit sensitive to running Carbonio intakes. As suggested, either try the stock intake or take the enclosure off the carbonio.

Had a look at your logs as well. Nothing really stands out in there. Have you tried going to the Unitronic website and opening a ticket with tech support?

Thought this was the case originally, so I took off my Modshack and ran an open filter. Nothing changed.

So then I installed the stock intake. Still nothing changed. Now I'm running the Injen and it ran beautifully for two weeks straight before things went right back to the way they are now.

I've got Uni taking a look at my logs, so we shall see what they find.

Notable: this morning I tried to reproduce said hesitation when going wot above 3k rpm and everything felt normal.... Perhaps my car is possessed and REALLY doesn't like going to Field's Volkswagen hahah