Fitting a manual boost controller ?

[wild willy]

Right, still have the mbc connected with the n75, but still I have a problem!!

Even though I have turned the boost down to 15 psi , it will still go into ****ing limp mode

Take for example tonight. I ran some friends into town just cruising in 5th gear. Cruised most of the way home but thought while I was on the motorway I would see how the car would go if I dropped to third. So down to third , accelerate and then limp mode.

The most annoying thing is that the problem is completely intermittent.

Could I be looking at a dodgy n75 valve ? Im going to run the mbc on its own without the n75 to see if there is any improvement

have you been adjusting the actuator.

 

[ibizacupra]

what code has it logged?

 

[gregorcupra]

I really dont think its a boost leak due to how intermittent the problem is, but Ive had the issue over a year now so I have no idea.

I havent touched the actuator at all , and the code is 17965

 

[ibizacupra]

I really dont think its a boost leak due to how intermittent the problem is, but Ive had the issue over a year now so I have no idea.

I havent touched the actuator at all , and the code is 17965

17965 P1557 Charge Pressure Contr. Positive Deviation

aka you have asked it for more boost than it was mapped for so deviation had tripped in.
you are stuffed with this unless you get a map to suit deviations and or exceeded coded out

 

[gregorcupra]

Yeah I see what youre saying but the idea behind the boost controller was to turn dwn the boost , due to it saying it was overboosting. However , now that Ive turned it down I get the same code.

This morning I piped the mbc as others have suggested, disconnecting the pipework but leaving it plugged in. I took the car out and adjusted it to 17/18 psi. It has mate a noteable difference , because where before the car would shoot way up to 20 it now goes to around the 17 mark and holds a lot longer.

I thrashed the car about for a good 20 minutes / half hour and got no limp mode but theres only so much thrashing I could do ! The annoying thing with this problem is that I could have continued driving say for another 5 minutes and it may well have gone into limp!

I scanned for fault codes when I got home only to yet again find 17965.

Thanks for all the help guys

 

[ibizacupra]

its the different responce from mbc to n75 which just slides outside the stock +/- 250mb deviation limits

 

[gregorcupra]

hmm gets more and more confusing

Think ill just set it alight !

 

[ibizacupra]

i think some folk plumb n75 along side mbc to clip the spike, but without adding more boost

 

[tarzan]

i think some folk plumb n75 along side mbc to clip the spike, but without adding more boost

correct to get the spike away. not to adding boost.

 

[ibizacupra]

correct to get the spike away. not to adding boost.

kinda what I said fella

 

[tarzan]

kinda what I said fella

i know

 

[aaron-gardner]

dont mean to drag up old threds but this is a good one in regards to fitting a mbc.

what i want to know is if im running my mbc in replace of my n75 which is electronically connected but not plummed into anything. and the mbc is used to take over. what i get is peak boost in all gears all the time. i got a stock 180bhp cupra so im assuming that its normal peak boost is 0.8bar as this is what my gauge gives me on the n75. so what i have done is set my mbc so that it peaks at 0.8-0.85 bar and it only drops about 0.05 bar and holds until the redline. the power delivery is smoother and it does not jerk at low revs. what i want to know is it safe for the car to run this way without causing any damage as im not requesting more boost but it has however got better boost when its held.

 

[aaron-gardner]

also my n75 peaked at 0.8bar but then in 4th gear would struggle to always hold 0.6bar. it seemed to trail off in every gear. no boost leaks and as said with the mbc fitted its a solid boost.

 

[tstrahonja]

I am also wondering...my boost is a bit lower than requested..requested is 1 bar (stage 1, k03) and i get 0.8, 0.85.
Can i use MBC and set it to 1 bar?

 

[ibizacupra]

log block 118 and see n75 duty cycle. if its >95% its pegged and turbo is already flat out. MBC wont add antyhing if so

 

[tstrahonja]

I did log block 118 some time ago looking to find a solution to my problem..
n75 values were normal..around 80 on low revs, 55 on mid revs and around 65 on higher revs..
That should be ok, right?
What i find weird is my knock table, block 020
All zeroes..



Should i open a new topic cuz this is a bit offtopic now..

 

[ibizacupra]

I did log block 118 some time ago looking to find a solution to my problem..
n75 values were normal..around 80 on low revs, 55 on mid revs and around 65 on higher revs..
That should be ok, right?
What i find weird is my knock table, block 020
All zeroes..



Should i open a new topic cuz this is a bit offtopic now..

either it has not timing pull, which leaves some margin for adding more until you do see some CF's or its not working.. Add some timing 2-3 deg at a time with unisettings and relog.. you will likely see some CF's appear

 

[tstrahonja]

I am not familiar with unisettings nor have the access to it
Is it possible that the timing pull is not working? What should i check if that is the case?
When i bought it 5 years ago, it was fast..much faster than now..then something happened and i just lost performance..

 

[ibizacupra]

I am not familiar with unisettings nor have the access to it
Is it possible that the timing pull is not working? What should i check if that is the case?
When i bought it 5 years ago, it was fast..much faster than now..then something happened and i just lost performance..

you do> http://www.unitronic-chipped.com/uni-setting

download from here, use your vagcom cable

 

[tstrahonja]

Oh..nice
Although, i have to admit that i dont feel very confident messing with my ecu..
But i will try..
Is it possible that timing pull isn't working, need's to be reset or something like that?