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No boost .
Posted: Sat Mar 04, 2017 6:07 pm
by Devcos666
So ladies and gents , give it wot and it boosts as it should , back off the throttle and wot again and no boost .
Swtich off and start again and its fine again until i let off the throttle and go to wot and no boost ?
I have scanned the car today and no errors are present , any ideas thanks .
Re: No boost .
Posted: Sat Mar 04, 2017 6:17 pm
by Shoppinit
If there are no codes then it sounds like a dumb component getting stuck / failing. I'd probably start by changing the N75 and DVs. Good preventive maintenance that anyway.
/actually I'd start by logging the boost values when the problem occurs.
Re: No boost .
Posted: Sat Mar 04, 2017 6:25 pm
by Devcos666
Thanks for the quick reply , i have changed the DVs and its the same , i have a spare n75 so i will try that next cheers .
Re: No boost .
Posted: Sat Mar 04, 2017 6:29 pm
by Shoppinit
If that doesn't work then you need to see whether the ECU is requesting boost or not.
Check the condition of your vac hoses while you're in there.
Re: No boost .
Posted: Sat Mar 04, 2017 6:39 pm
by Devcos666
Cheers yes i will check vac lines although the ones i can see have been replaced with quality silicone hoses .
I will start again tomorrow fingers crossed .
Re: No boost .
Posted: Sun Mar 05, 2017 2:23 pm
by srichards
Waste gate or similar stuck open? I'd hope that would raise a code though.
Re: No boost .
Posted: Mon Mar 06, 2017 11:47 pm
by sweegie
Sounds like the ECU is putting the car into soft limp due to an overboost condition.
Has it been mapped?
Re: No boost .
Posted: Tue Mar 07, 2017 9:48 am
by Shoppinit
^^That's what I thought initially, but there should be a DTC if that's the case.
Re: No boost .
Posted: Thu Mar 09, 2017 5:50 pm
by sweegie
True, unless it's been mapped by some bampot who's fudged more than they should!
Re: No boost .
Posted: Thu Mar 09, 2017 6:07 pm
by Shoppinit
We'll probably never know...
Re: No boost .
Posted: Thu Mar 09, 2017 6:26 pm
by bam_bam
sweegie wrote: ↑Thu Mar 09, 2017 5:50 pm
True, unless it's been mapped by some bampot who's fudged more than they should!
Bampot? I'm banking that one.
Re: No boost .
Posted: Thu Mar 09, 2017 9:25 pm
by Devcos666
Okay so i didnt get round to looking last weekend due to work and <beep> weather .
I have no history regarding a map , so am still going to go the n75 route next and see what happens .
Cheers .
Re: No boost .
Posted: Mon Mar 27, 2017 8:02 pm
by Devcos666
Right i finally got a bit of time to get the airbox mafs off and noticed the short vac line to the fuel press reg was split in two .
So i replaced this but also noted another line sort of inbetween the dv,s and then it disapears down by the right hand headlight ? This line is spurred off a larger diameter hose under the right dv , i cant seem to find where it goes .
Thanks for the help so far .
Re: No boost .
Posted: Mon Mar 27, 2017 8:20 pm
by Shoppinit
Sounds like it's going to the N80 Evap valve.
Re: No boost .
Posted: Mon Mar 27, 2017 8:25 pm
by Devcos666
Could this also be part of the problem ? What does the N80 valve do .