casa 3.0 tdi q7 remap issues...

tony1966

Registered User
hi flks-can i pick your brains
recently bought casa engined 3.0 tdi q7 [09]
it had sometimes egr fault showing on vcds scan-mostly cold start-very occasional limp and glowplug light
it threw two egr related codes the solenoid and egr flow itself[lost the pic i had of them sadly]
no other engine faults whatsoever[75k car

so long and short of it decided to get remap and egr/dpf/flap delete as egr is a pita on these
got it remapped and it still sometimes went on limp-no storedcode on ecu,no eml or glow light[that was within a day of map-i tried to blank egr at front cross pipe and it immediately went onto permenant limp until i removed the blank
i could still see the egr function,required and actual flow,plus the flaps,and even test flaps on vcds-is this right on a deleted car?
the mapper gave me another flashed file but car is far worse,if it sits idling or going slow for any length of time it will go on limp-again no stored codes,and i can still see all the egr /flap stuff on vcds
same when fitting the front blank,permenant limp until removed

the mapper said it was the dpf doing this but as it was fine and flowing well before the map[and goes like a train when on the open road] i havent yet gutted it,but what i did do was undo the 3 turbo to downpipe bolts and pull the pipe back off them so removing any potential backpressure-still onto limp[and loads noise of course]

reluctant to gut dpf as i am then commited to stay deleted as it were and its not working-whereas at the moment i can get my original file put back on the car and at least fault find etc as i have no codes for this on the remap

anybody offer some some advice[i know find another mapper will be one but i am kinda stuck atm but my hand may be forced as he has gone onto radio silence mode]

i should maybe have either replaced egr/cleaned up or used a one stop map/gut service

would it help blanking egr at turbo end -looks a pig to get into tbh and i have heard the torx can break there

your thoughts please,i have at the moment 2 tonnes of very expensive to tax scrap metal at my door...
 

tony1966

Registered User
hi-i am in fife,scotland
i am trying to get him to fire the original file or even the first one whereby i could actually use the car and check all the egts etc and live data when it goes into limp-which to be fair wasnt terribly often until this map
i am baffled how i can see the egr and flaps working on vcds yet they are deleted-is this the way it works

he said the first map was egr partial delete and the one i have now is egr total delete

also baffled why it goes onto limp when i blank of the egr at front of the engine as it fires into the alloy pipe with the shut off valve on it...unless it has to be blanked at rear for some reason,but then it will take longer to warm up etc
 

tony1966

Registered User
also do you think it would be prudent to ask the "mapper" to fire the original file back onto the ecu...

when i say mapper somebody else writes the files for him,he merely fires them on the car after removing and sending out a copy of your own file which o believe is modified
i have had it done before on several vehicles deletes etc without issue-usually to cure something underlying-it hasnt worked very well in this case lol
 

tony1966

Registered User
today i had map 1 put back on-it was in limp most of time-i had changed the air cleaner[fairly choked in the interim]
egr actual was 100 odd above required at idle[remember egr deleted...hmm] just slightly more flow due to new air filter perhaps..?
iirc the calculations for flow are from the maf so disconnected that and no more limp
the egr difference will also be why its full time limp when i blank it at front

will see where i stand after dpf is gutted,if flow evens out good and well-thats what i hope but i feel the map writer dude needs to turn off the signal and probs another few bits on the egr system

i had also checked the maf actual vs target at start of the issues and they seemed fine so hopefully not just a maf issue after all the grief
 

tony1966

Registered User
update for anybody who has read this-dpf gutted today-mapper dude pronised me everything would be ok after it was done
car still in limp mode,contacted the gent and will see what he says,i am almost 100% certain the egr is not deleted properly from the map
 

tony1966

Registered User
egr connector currently unplugged but makes no difference whether plugged in or not tbh
the solenoid being unplugged [to the right of it]seems to be the difference between limp and not
mapper dude now tells me some mercs and hondas he remaps need the egr unplugged...

but hey ho -it seems fine now,not had a limp episode as yet scince unplugging solenoid,stays like this i will be happy enough,although i would like the plugs to be in place
 

EG-Nath

Registered User
im a little knowledgeable in this area :)

if the ecu remap hasnt been done accordingly for you to remove the egr and blank it then the engine will indeed go into limp mode (there's effectively 2 different remapping types for egr's 1. if theyre functional and still fitted, 2. if theyre not functional are coming out)

also some dpf systems use the egr as part of the regeneration, so that could be causing the limp mode too
 

tony1966

Registered User
the bloke did mention full and partial delete and the way they were fired onto the ecu diffring between the two maps that were tried

i have done probs 100 miles or so,varying temperatures/load and not yet seen limp mode,performs very well-thus far
going gently there is a bit better fuel consumption as a wee bonus,most of my runs are short ,not fully up to temp ones,thats why i have blanked at front as there will still be a bit exhaust heat to aid fast warm up via the coolant -up to the egr valve at least-added to the fact that its a pita to blank at the turbo end...

with the engine cover on all looks fine-if emmision equipment inspections become more stringent/robust i can plug it in for mot,or make it look connected-if the car continues to run as is i am happy

what sensors am i effecting unplugging the egr solenoid?-it surprises me that this makes the difference it does-although when juggling it to release electrical connector i heard a" ping" noise inside it-like a spring releasing,i dont want to plug it back in even to try as all is well atm
 
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