1.8t agu boost issues new info added, still not sorted :(

[corrado_sunderland 0]

just got the car back this morning from andy who sorted some wiring issues out and although all codes are cleared from ecu now and all wiring is ok ish (except for me rev gauge going off when i put me heaters on face :lol: :confused4: ), the car acccording to the boost gauge is only doing 3psi still :confused4: and its feels flat as a witches tit. car drives fine etc except there is a little play in throttle body butterfly that makes idle cough from time to time but im unsure what else other than a boost leak that would be causeing the issue, surely it would whistle like made with a boost leak of 4 psi?

:D

anyone got any help here so i can hopefully get her running full standard beans over weekend :D

[VR6Joni 0]

Recirc valve stuck open?

[corrado_sunderland 0]

Recirc valve stuck open?

 

 

recirc valve? where that located m8, and its got a forgre 007 dv on that what ya referrin to bud?

[VR6Joni 0]

Recirc valve stuck open?

 

 

recirc valve? where that located m8, and its got a forgre 007 dv on that what ya referrin to bud?

 

Yep, thats the one.

[corrado_sunderland 0]

blanked the dumper off last nite m8 and no different other than some turbo chatter, still same 3psi so must be something else :confused4:

[junkie 0]

N75 valve faulty possibly and not controlling the boost, or wastegate stuck open. Or is the n75 plumbed up correctly. It's the 3 port boost solenoid.

[corrado_sunderland 0]

N75 valve faulty possibly and not controlling the boost, or wastegate stuck open. Or is the n75 plumbed up correctly. It's the 3 port boost solenoid.

 

 

it was plugged into vagcom yesturday and all faults were sorted and im guessing n75 would of shown up? as for wastegate that could well be an option as the burk i got the engine off bent the bracket over and the actuator bar was bent and straightend best it could, any more and it would of snapped, think that could be the ticket then?

 

and the n75 hasnt been touched since i got the engine in so should be plummed up correctly i assume as mk4 it came from drove fine according to me m8 i got it off, and i doubt he'd lie cos he knowsfine well id be straight at his door not very happy :lol: :confused4:

[mrbeige 0]

Sounds like it, most probably stuck a little bit open.

[corrado_sunderland 0]

Sounds like it, most probably stuck a little bit open.

 

apparently a new actuator and bracket from stealers is about £20 shirley that cant be right :lol:

[mrbeige 0]

Sounds like it, most probably stuck a little bit open.

 

apparently a new actuator and bracket from stealers is about £20 shirley that cant be right :lol:

Sounds ok to me, and don't call me shirley! haha

[corrado_sunderland 0]

Sounds like it, most probably stuck a little bit open.

 

apparently a new actuator and bracket from stealers is about £20 shirley that cant be right :lol:

Sounds ok to me, and don't call me shirley! haha

 

 

:lol: poetry in motion, ihad a look at the bar and it doesnt seem to bent to me but that only from looking at it in the dark so at weekend ill have to loosen it off and set it up again so its tight and see if it works then at least i know its only down to actuator, just got a ko3s there i think, as long as me o/d increase gets accepted of course :grin:

[corrado_sunderland 0]

not the actuator, checked it today ive turned it up alot and still only getting 4psi, checked n75 for leaks and ok and except for nity gritty piping ive checked most the other joins so far no no avail so am stumped :confused4:

[junkie 0]

Just have to sell it to me then mate.

[junkie 0]

How about the MAF, not sure but I think the ECU can hold back boost if the MAF is faulty to prevent running lean and killing the engine. Also the N75 may not be leaking but may be foobared or it's possible it's plumbed in wrongly. Also both faults may not show up on a scan check depends how it's failed, that's about as far as my knowledge goes. Try running the turbo on actuator spring pressure, you need to plumb the actuator nipple hose straight onto the turbo compressor housing if it then boost better upto around 0.7 bar then it's the N75 that's faulty and if it's still not right then it will be a actuator issue.

[corrado_sunderland 0]

How about the MAF, not sure but I think the ECU can hold back boost if the MAF is faulty to prevent running lean and killing the engine. Also the N75 may not be leaking but may be foobared or it's possible it's plumbed in wrongly. Also both faults may not show up on a scan check depends how it's failed, that's about as far as my knowledge goes. Try running the turbo on actuator spring pressure, you need to plumb the actuator nipple hose straight onto the turbo compressor housing if it then boost better upto around 0.7 bar then it's the N75 that's faulty and if it's still not right then it will be a actuator issue.

 

 

does seem the problem could be n75 yet, few people have suggested then failing even showing no fault codes, its got my head done in now like :lol:

[corrado_sunderland 0]

ok ok ive give up and got another genuine n75 of ebay, me m8s had an a3 that did the same all the time with same symptoms so i just said sod it and got one, got me new turbo coming this week too :) then remap next week and 240bhp rado here i come, yeah baby :rofl:

[junkie 0]

Hope it works but like I said you could have tested it to see if it was faulty before spending.

[corrado_sunderland 0]

Hope it works but like I said you could have tested it to see if it was faulty before spending.

 

 

its the original one anyway, its done 80k so about time for change and maf working ok as i tested that lastnite and it drove the same so other than a boost leak around turbo its all it can be really

[corrado_sunderland 0]

right after new map and test drive tnite :mad2:

 

car spec

1.8tagu in me rado with front mount silicone tip, kos3 and remap- 007dv yellow spring and no shims added

 

ok so ive spent alot of time going through all the possbile causes for the car not boosting properly, ive changed n75, maf, lamda (all genuine parts) temp sensor and put new plugs in (ngk plats),

 

The car ecu had communication problems but the lad now is aware of how to sort this as he needed to add an extra power pin on ecu but in the mean time he added a chip for me based off another car map he did with exact same set-up and soldered onot bored direct (car will get live mapped in new year now hes aware of how to get it communicating). The car should boost to 20psi with the new map and does not to much great and overwhelming frustation asi changed everything now that would cause boost retardation due to fueling.

 

The car pops and bangs so i think is overfueling still and for example of you got flat out in 2nd gear will achieve a steady 10 psi of boost, 4th gear manages 15 then drops to 14 and holds most of revs from what tests ive managed as i ran out of road earlier. 5th gear appears the same however earlier on the motorway it did hit 18psi for one time only when boosting up a hill but other than that it will not ever hit more than 14-15psi and it has me stumped, ive changed everything what the hell is causeing it to still not boost fully and never hold more than 10-15psi, and at times it even winds boost back from 15 then holds 10psi e.g. in 3rd i think it did it.

 

It should be achieveing 20 psi with this map and im greatly confused and need help here as im completely stumped now and have changed everything i can think of could it be down to needing shims in dv? or would it never of hit 18 ever at all if that was the case?

[DANG60 0]

Sorry this wont really help you but my car with a k03 s spikes at 22 and drops down and settles at about 13psi. Cars not hitting limp mode or anything is it? A constant 20 psi seems like a big ask 15 seems nearer the mark for a small turbo like that?

[corrado_sunderland 0]

Sorry this wont really help you but my car with a k03 s spikes at 22 and drops down and settles at about 13psi. Cars not hitting limp mode or anything is it? A constant 20 psi seems like a big ask 15 seems nearer the mark for a small turbo like that?

 

 

i would expect about 18 constant really and 22 spike from what ive seem on the net, its got me sick now... it should deliver same boost- every gear period and not being bollox on fuel like it is aswell, im getting 45 mile to a tenner

[DANG60 0]

not a knackerd recirc valve is it? i.e. dump valve

[corrado_sunderland 0]

not a knackerd recirc valve is it? i.e. dump valve

 

?

its a pretty brand new 007dv with yellow spring, i have thought that possibly its not shimmed up enough to handle the boost?

[DANG60 0]

maybe, you tired putting it in the other way round? my mate had a problem with his mk 2 20v and he did this and it sorted it for him. may be worth a try?

[corrado_sunderland 0]

maybe, you tired putting it in the other way round? my mate had a problem with his mk 2 20v and he did this and it sorted it for him. may be worth a try?

 

putting the spring the other way round ya mean?