Overboost ! Not acheiving requested ??

A

ant schof

Registered User
Joined
Jan 1, 2011
Messages
162
Reaction score
3
Points
18
Location
NULL
Hi All ,
I've been going round in circles and could do with some help . I had my 02 plate S3 Bam , remapped six weeks ago only acheived 239bhp but 259 lbft torque was expected 269 bhp . No fault codes stored . I have replaced N75 , MAF and DV007p all brand new , then decided to bite the bullet and replace the turbo . Replaced turbo with a refurbed K04 023 and new manifold , pipe werx 3inch down pipe and sports cat . Went back for mapping again today and only acheived 225bhp !! With an over boost fault code found , mappers tell me the boost is'nt making requested . I've checked all pipe work for splits/leaks nothing found , where do i go from here ? Any help apreciated as i'm start to loose love for the beast !!
 
No smoke tests carried out , just logging with vag com , was told that i have an over boost upper limit exceeded fault ! then showed me a graph where boost was'nt making requested ! So what to do next ? Anyone with vagcom in cornwall think i need to get some logging of my own done ?
 
Well the car is overboosting, i.e. making too much boost pressure. Thus throwing the car into component protection mode (Limp mode).

One aspect of limp mode is that, when activated, it restricts the amount of boost that can be generated by the turbo.

The person who "mapped" (use that term loosely) doesn't appear to have a clue I'm afraid fella.

You need to start with clearing the codes and having the car logged to asses what boost the engine can produce (be it too much/too little) when the fault memory is clear and limp mode is inactive.
 
To be fair...

This mapper is probably using a generic file sent from America/China/wherever and is sending it backwards and forwards to get it tweeked.

IF the OP's hardware was up to it then the software would probably be faultless; maybe not the best but I think it is mightily unfair to just go "**** mapper, what a bellend." After all nobody goes out to deliberately make a customers car ****. The OP's car could quite easily be a total shed for all we and he knows; how many regular members who we've thought know their onions have had their cars turned away or found to be hugely faulty by more than one tuner? I can think of 5.

The OP could easily be just as at fault here as the tuner in my eyes, for not ensuring his vehicle is ready for tuning. The tuning is simply exposing hardware faults which already existed but was made up by the low state of tune the stock engine is in.

I don't think there's anything inherently wrong with quick flash tuning, but you need to be competent enough to ensure that your own hardware is up to scratch before hand. If not pay a few £100 more and get a specialist like Bill or Niki to do it ALL for you.

My tuppence. :)
 
Last edited:
  • Like
Reactions: superkarl
Ok just a bit of clarity here ! Firstly my car an 02 plate S3 Bam is well maintained by myself i can assure you its not a shed i've owned it for just over two tears now with just over 90k on the clock and have covered over 20000 miles in my ownership . Before the remap i thought it a good idea to drop the sump and replace the pick up pipe , no blockage found but for peace of mind another job done on the list . I have always serviced the car regularly , went to celtic tuning for a custom not generic map . At the first visit the remap produced 239 bhp and 259lbft of torque , a scan was done before the map and no codes were stored . The map was meant to acheive 269 bhp . So was advised it could be a faulty MAF or other hardware issue . Bear in mind they are a tuning company not a garage . To be fair they have spent many hours on the car and i hav'nt been charged for this work at all . It was my decision to replace the turbo with a refurbed unit , and i was right in doing so as the waste gate housing and manifold were both cracked . At the same time i thought a good opportunity to upgrade the downpipe and cat . The problem i have currently is at the subsequent visit to celtic the car only acheived 225 bhp on the dyno , the same previous map still on the ecu so a drop in power !? And now an overboost fault stored to boot , i like to do most of the work on the car myself , i do realise i'm now in logging territory and am looking at a good vag specific garage in cornwall to help resolve the problem . I have no grudge with celtic as they are a just a mapping company , not a garage . Perhaps i should have gone to vag specific tuner in first place , experience makes you wiser ! Any input to soultions to the over boost issue would be welcome .
 
Celtic Tuning are NOT bodgers, so all of the below about the quality of mapping is very unjustified. Hence why I wasn't so quick to jump the gun!

There must be something somewhere that's been missed. Have you been dealing with Gareth?

I'm from Plymouth so you can't be that far away from us, and I have a fair few friends cars which have been mapped by them. All of them are great and log perfectly, two of my friends have MAF-less AGU setups in Mk3 Golfs and the mapping on them is just as good as any stage 2 map I've ever driven. Both of which have been mapped for over a year.

Come to Tavistock and see Phil Miller and I if you'd like; Phil can smoke test the vehicle for you and we'll see if there are any boost leaks. They're the usual culprit for overboost. Whilst Phil will probably ask for a coupe of quid for the work you'll learn a lot along the way and it's always nice to meet new people :)
 
poor mapping tbh, the limit between the boost you are able to produce and the boost they are asking for is beyond a specified limit because they don't know how to set it correctly. The logs should have been able to show a poor MAF coupled with the rolling road read out, in theory one should corralte to the other so as to give an indication if things are not reading correctly
 
Refurbed turbo? I'm assuming ALL components are genuine because if they are copy parts, especially the hotside, that would explain some of your issues...
 
slowcoach3 said:
Refurbed turbo? I'm assuming ALL components are genuine because if they are copy parts, especially the hotside, that would explain some of your issues...
Click to expand...

Overboost limp mode is because the max threshold map hasn't been set high enough. Its not an actual over boost but maf sensor reading has gone past the map limit.

Midland turbo copy hotside and leaking actuator possible likely cause of other issues
 
not achieving requests and not making expected power... your cracked turbo would likely have explained this.. Good condition car you say, but all too often that means nothing.. nor milage being any guarantee of "health"

Replacement turbo.. if non-genuine hotside used for example, would/could cause boost creep and if the maps not set to allow for much deviation limp mode ensures.. Some mappers raise this limit more than others.. Whot knows what celtic do or dont do

Hoping your hotside is'nt like this one I had to port out for a guy on here who also had max boost exceeded code, and boost creep (on his std map)
BEFORE
183080_368754313242660_418244003_n.jpg


AFTER PORTING
393122_369013676550057_1603597088_n.jpg


"Tuners" should be able to fixed issues they will always find.. else they're not actual tuners, just blokes who flash codes into a car.. Thats not Tuning..
 
  • Like
Reactions: ant schof and Vex182
OK bit of an update people , I've pressure tested the actuator with a foot pump and the rod starts to move out about an inch and then sinks back down not holding pressure and not opening the waste gate . I've also manually been able to open the wastegate and full movement and return acheived . Think this is my overboost fault ! I'll be getting onto midland turbo first thing on tuesday , will ask about the hot side porting , really don't want to have the turbo removed again ! Thanks all for your input .
 
Now that i've established my actuator's at fault . How the hell can it be removed in situ , i've just had a look at access and removed the air box . One actuator bracket bolt can be reached without too much trouble the other is blocked by the coolant banjo bolt , how can you get to this withouth removing the turbo !??? the mani is right above the banjo bolt and to say its tight is an understatement !
 
thats my turbo badger 5 done, great job btw... its only the three wierd hex nuts from above from mani to turbo then you should be able to move it enough on the flexi part of the downpipe to get the top oil/coolant hoses off? maybe? good luck mate.
 
thanks for the input justarn . I'm hoping this is possible , would the turbo support bracket bolt have to be removed too . I take it with the turbo undone from the mani there is enough space to get an allen key bit to the coolant banjo by the actuator support nut , can anyone confirm this please .
 
the bracket has got a bit of movement, might be lucky mate... i was messing with my bracket yesterday bending it around with some mole grips trying to get that darned nut in!-)
 
Right had a big chat with Midland Turbo today , ref my refurbed genuine K04 !? and inoperative actuator !! thanks Bill for pointing out the throat problem , they've agreed to send me a brand new borg warner k04 with uprated 360 degree thrust bearings at no additional cost . So light at the end of the turbo tunnel me thinks , booked in for fitting next week :)
 
  • Like
Reactions: Alex C
You must log in or register to reply here.

Similar threads

Gizmo20VT
AFR not meeting requested
Replies
8
Views
844
badger5
badger5
Effect
17705 + car not making requested boost
Replies
1
Views
903
Effect
Effect
Voodoo
Opinions requested
Replies
33
Views
2K
S3IZZO
S
ALPINE
Pics requested...
Replies
0
Views
762
ALPINE
ALPINE
s3gazz
New logs as requested
Replies
21
Views
1K
badger5
badger5
Top
Back