[MabsM]

Hi all,

the 9-3 is at it again. really sluggish when accelerating...then bang on the motorway all aceleration disappears and limp home mode appears but not EML and no codes what so ever. reseting with obd or turning off and on takes this away and sometimes it comes back sometimes it stays gone. general driving on normal street roads it is not too bad.

conditions

9-3 Tid 1.9 (120)

• DPF manual regen 2 weeks ago, also DPF replaced 2 years ago (approx)
• EGR blanking plate fitted as this was causing issues (sluggish, black smoke, instant issues) - would changing this, with original or alt part??
• changed MAP (with a cheap replacement to experiment) the MAP was coked up when i checked.
• There could be a problem with MAF i cleaned this previously but disconnecting and connecting sorts this really.
• Turbo replaced little over 2 years ago.
• Most importantly under load the car goes into limp home (on Gear 5+6)
• sluggish to accelerate between 1k-2k revs.

PLEASE Any help would be great as i really have not got time to mess around and throw money at it, as o previously have done this and faffing around cost me money when it was simply a TB that needed replacement.

Thanks

 

[djstan]

Just a suggestion, but if it's happening under load, have you checked the condition of the rubber pipes - it could be that a hose is collapsing under the pressure from the turbo? (Sorry I can't be more descriptive, but I saw it on an Audi forum once a long time ago and 'collapsing hoses' became quite common )

 

[aerojon]

if there is no eml then it's not going into limp home mode.

 

[MabsM]

It goes in to limp home mode, loss of tubro and power limited.

Eml does not come up at all.

I will get somebody to look at the turbo piping etc

 

[aerojon]

No,like i said no eml,no codes,no lhm..limited performance on the sid is not lhm..

 

[MabsM]

Ok i see,

Well it goes in to limited performance mode.

Any thoughts on what this could be?

 

[cjapeterborough]

You do get the limited performance message when the boost control valve is disconnected.
Check the connection and wiring.
I would check all the vac pipes from the vacuum pump through the valve and down to the turbo
actuator also - check to see if you have oil in them apparently it can get through the vac pump seals.

 

[MabsM]

Thanks cjapeterborough,

Update - I replaced the EGR with a working used part as to test the theory of egr flow rate malfunction, this did not work...

I recently got the vac pipes checked from the boost control valve and they were degraded,i have only change the vac pipe to the manifold and i seem to have better boost than before but never had the time to change the vac pipe to turbo (or is it the actuator), i have ordered some pipes (cheap as chips) hoping this is the issue as it has been literally killing me whilst on the mway.

I am hoping the turbo is not problematic and having issues, any advice on what to look out for if the turbo is deciding to have issues?

ALSO on a different note randomly whilst doing a 3 point turn the stability control warning had come up on SID, no physical change and it disappeared on next start...any ideas?

 

[Caddyman]

As a matter of interest, how many miles is on this car? Also, no one has mentioned it, but have you thought that it could be an injector problem?

 

[c2kev]

Sounds like the problems I was having a few weeks ago, a 65mile drive at 75mph in 4th gear sorted it out. My problems were self inflicted but the symptoms were the same

 

[aerojon]

pipes are no good being cheap as chips if their going to collapse under vacuum..

 

[kez]

what do you mean by manual regen
was the dpf genuine or alternative after market
aftermarket cheap maps can lead to issues, have you still got old one
disconnecting and reconnecting the maf would in most cases not be a fault with the actual unit

replacing the pipes, as jon says though cheap is not always best and can prolong/add correct diagnosis.....define cheap

all these factors can actually add to problems not actually getting to the bottom of it, causing hair loss lol

follow the guide I did in the how to section re cleaning components, its based on the ttid but same principles will apply, whilst you are doing this and have the throttle body off get a torch and look into the manifold and try to judge how much build up of gunk is in there, but do not scrape it off on vehicle as you don't want all this **** to go into the engine which could add to issues, better to have it off to perform good clean. You don't have swirl flaps so no worries there

check the pipes on the bulkhead pressure sensor for the dpf, and also check the one that goes to the dpf, where it bends around the bulkhead can also give issues of splitting, also check these pipes not blocked

get someone to rev the engine and check pipes inc boost are not collapsing, these pipes could have hairline faults that show under load, using car cleaner or easy start around certain pipes will change the note in the engine sound if at fault so yes good idea to change pipes

doubtful injector fault as this would normally show limited performance

that's enough to be going on with for now

 

[Caddyman]

.....doubtful injector fault as this would normally show limited performance

I respect your expertise but this is clearly not always the case. My injector issue did not bring up any limited performance, limp mode or any trouble codes, stored or otherwise, and my number two injector was knackered.

 

[kez]

sorry caddyman meant to say "normally not show"

I remember your issue and yes to your statement, just something going on here that I believe doesn't point to an injector as too many variables I think