Flat spot at 5200rpm on 2.0T - Does yours do it?

[Poverty]

have you seen this on a dyno lot though or in logs or is it just an experienced thing.

logs, on a different car.

[Janner_Sy]

could yuo PM or post them up fr us to have a peruse over please.

[Poverty]

will have to try and get hold of them. Will post up some more info about it tomorrow night.

[Janner_Sy]

will have to try and get hold of them. Will post up some more info about it tomorrow night.

cheers boss

[NEWEY]

is there any updates on this ? as mine also does this around 5200 for a very short time, drops boost then picks back up about 5,500. mines a k03 running APS's map and turbo back milltek

still working on it, but if you are close to APS they could be the perfect guys to solve this issue.

i have phoned them up on monday and there looking into it. they think that it could be a problem with my sports cat but are getting back to me! ill give them a ring today and see if they have any updates.

[vRS Carl]

I had this problem

Stage2+ Revo. K03s Skoda Octavia vRS MY2007

Following Mods:

Autotech Fuel Pump
Full Miltek TBE
Neuspeed Turbo Outlet
S3 Intercooler
Relocated DV (including new revision D DV with no Rubber Diaphragm)
REVO Stage2+ Code
BSH Stage 2 Catch Can

I was having this problem and that was after a Major service in which the Spark Plugs were replaced (NGK Iridium). The Cam Follower was changed about 1k miles ago.

I recently replace the MAF & MAP and the car was taken on a Spirited Drive the car seems to pull a bit harder and it has gone away for now but i think it is to do with the ECU adapting to driving style as my Fiancee only drives 3 miles to and from work each day i only get the car if im lucky once a month  

Please don't ever blame your REVO map it couldn't possibly be that map no sireee there will never ever be anything wrong with the map 

Carl

[Poverty]

 

[NEWEY]

i had it when i first had the stage 1 map loaded. it was removed and put back on. but since the downpipe has been fitted and the updated map has been put on its come back again. Ed seems to think its a problem with my sports cat so is waiting to here back from milltek about a replacement. and will take it from there.

[Poverty]

i had it when i first had the stage 1 map loaded. it was removed and put back on. but since the downpipe has been fitted and the updated map has been put on its come back again. Ed seems to think its a problem with my sports cat so is waiting to here back from milltek about a replacement. and will take it from there.

You should send Ed the link to this thread. AMD thought similar when I told them to look at mine, but a new Blueflame DP later and it made no difference.

Still need to see if I can get those logs.

BTW if you lower the settings, the flat spot will disappear.

[Oli]

Did Jonnyc has a hesitation fault, and found out it was the wrong coil packs fitted???  ie those meant for a 20FSI engine!

[jonnyc]

Did Jonnyc has a hesitation fault, and found out it was the wrong coil packs fitted???  ie those meant for a 20FSI engine!

I did, but it was top end and to do with increased cylinder pressures from running 22psi boost over 7500rpm..

Yes the coil packs were wrong but thats not the same problem that some of you guys are experiencing..

BTW if you lower the settings, the flat spot will disappear.

When you say this, have you logged before and after, to see what the car is doing around this area in the rev range?

Also, does the problem arise more with increased boost or timing?

[NEWEY]

Did Jonnyc has a hesitation fault, and found out it was the wrong coil packs fitted???  ie those meant for a 20FSI engine!

I did, but it was top end and to do with increased cylinder pressures from running 22psi boost over 7500rpm..

Yes the coil packs were wrong but thats not the same problem that some of you guys are experiencing..

BTW if you lower the settings, the flat spot will disappear.

When you say this, have you logged before and after, to see what the car is doing around this area in the rev range?

Also, does the problem arise more with increased boost or timing?

aps made some adjustments to mine at the weekend, which i thought had cleared it but the problem has moved from 5200 in 4th to 5500 in 4th and now will only drop 2-3 psi  for a split second and then picks back up fine. so it is much better but is still there. which is why he thinks the cat could be at fault.

[GTIjames]

this has issue has plagued me for a fair few months now and have tried all sorts to fix it:

maf, sparks, coils, new intake (itg), replaced oem 'd' dv with forge dv, and also replaced my miltek downpipe when that blew a hole in the flexi flange

problems still remained - mainly in 4th and 5th gears and c5krpm, boost gauge suddenly drops from c20psi to 5-10psi for a second and then back to full boost

only solution i have found is too turn down the settings - i used to be b8t6f6 and am now b8t5f7

with the new settings the car does not stutter,

interestingly i noticed if I turned the timing up to 7 then the issue got worse and the stutter happended twice in the rev range

i am a vagcom beginner but this is a log i did at t7, can anyone advise what else i should be looking for

[Hedge]

You can log the cylinders individually to check for misfires and timing correction.

I think its Block 15 off the top of my head.

[GTIjames]

read this from mike @ forge regarding their new actuator:

could this be what we are experiencing? are oem actuator spring is failing over time and causing the issues...

"Actuators are not offered to address shortcomings with software.

They are made to address shortcomings with the OEM actuator that software does not compensate for.

Similarly to how a weak blow-off valve can leak on the pressure side of a turbocharged application, a weak wastegate can leak on the exhaust side.

The stock actuator has a soft spring in it (~ 4PSI) that doesn't effectively keep all of the exhaust gas spooling the turbo in the most efficient manner all the time. Too much exhaust gas pressure can force it open effectively causing an exhaust gas leak that limits spool and boost potential. If you figure that you are pumping 15-20 PSI into the intake side of the motor, you will have an equivalent amount of exhaust gas pressure coming out of the motor on the exhaust side.

This is a phenomenon that a lot of people experience without even realizing it. Under a high load condition, such as a wide open throttle pull in 4th, 5th, or 6th gear, boost will quickly climb to a peak value and immediately fall off and fluctuate wildly up and down and which point you will hear a fluttering effect from the engine as the ECU tries to keep actual boost in line with requested. This is far more prone to occur on a smaller turbo at higher boost levels (more air flowing through a smaller space) than a larger turbo at lower boost levels.

No amount of tuning or additional N75 duty cycle will prevent the wastehate from being blow open prematurely by exhaust gas. N75 duty cycle doesn't apply vacuum to the actuator to keep it closed. It only delays the time that pressure signal is held back until it is sent to open the actuator.

The only way to prevent this occurrence is to increase the spring tension of the actuator. Adjusting the stock unit will have a similar effect but to a lesser degree because your working with an altogether lower spring tension, and adjusting it will only limit its travel and flow potential. A replacement unit with a stiffer spring will help to spool the turbo in the most efficient manner possible by keeping all of the exhaust gas flowing over the impeller wheel."