Boost Problem - please help

[Callumc]

Hi there. I have a 2001 Seat Ibiza and am quite new to this site, I wont go into detail on visual mods. Basically I bought the car off of my brother about 2 months ago (he has been a member on this site) It has had a remap years ago and was pretty standard. My brother fitted an exhaust sytem, dump valve,intercooler, induction kit, bypassed n249. The car started to boost fine until 5th gear it would go into limp mode and faults - 17963 would come up and so would 17965. He then fitted a manual boost controller (he was told the remap could be too much for the car with the current remap causing overbost). The manual boost controller sorted it until I bought it and the problem is back. We turned the boost down and it was still there, so I fitted an n75 valve - all seemed much better. I then turned up the boost and the faults are back - could the n75 have blown? I do feel like a saw a massive difference but don't know whats happened. Basically I am trying to find the problem or I may need a remap. I was thinking about getting another new n75 and seeing what happens

I hope someone can help. Thanks guys.

 

[ibizacupra]

Hi there. I have a 2001 Seat Ibiza and am quite new to this site, I wont go into detail on visual mods. Basically I bought the car off of my brother about 2 months ago (he has been a member on this site) It has had a remap years ago and was pretty standard. My brother fitted an exhaust sytem, dump valve,intercooler, induction kit, bypassed n249. The car started to boost fine until 5th gear it would go into limp mode and faults - 17963 would come up and so would 17965. He then fitted a manual boost controller (he was told the remap could be too much for the car with the current remap causing overbost). The manual boost controller sorted it until I bought it and the problem is back. We turned the boost down and it was still there, so I fitted an n75 valve - all seemed much better. I then turned up the boost and the faults are back - could the n75 have blown? I do feel like a saw a massive difference but don't know whats happened. Basically I am trying to find the problem or I may need a remap. I was thinking about getting another new n75 and seeing what happens

I hope someone can help. Thanks guys.

17963/P1555 - Boost Pressure Control: Upper Limit Exceeded
Possible Symptoms
Reduced power output
Limp mode
Possible Causes
Boost Pressure too High
Hoses/Pipes incorrect connected, disconnected, blocked or leaking
Charger Pressure Control defective
VNT (variable nozzle turbo): nozzles stuck
Solenoid Valve for Boost Pressure Control (N75) defective
Possible Solutions
Check Hoses/Pipes to/between Components
Check Solenoid Valve for Boost Pressure Control (N75)
Check / Clean / Replace Charge Pressure Control
Check / Clean mechanism for variable nozzles


17965/P1557/005463 - Charge Pressure Control: Positive Deviation
Possible Symptoms
Reduced power output
Limp mode
Possible Causes
Boost Pressure too High
Hoses/Pipes incorrect connected, disconnected, blocked or leaking
Charger Pressure Control defective
VNT (variable nozzle turbo): nozzles stuck
Solenoid Valve for Boost Pressure Control (N75) defective
Possible Solutions
Check Hoses/Pipes to/between Components
Check Solenoid Valve for Boost Pressure Control (N75)
Check / Clean / Replace Charge Pressure Control
Check / Clean mechanism for variable nozzles


Got VCDS or access to it? (www.ross-tech.com)
log block 115

disconnect n75 electrically and see what boost it does then... confirms what the actuators wound up to.

5psi is std

 

[Callumc]

I can be driving the car and it goes into limp mode after 20 minutes, other times it can go into limp mode as soon as i put my foot down in 5th gear

 

[cus]

mine did the same.. turned out i have a leak from a vac pipe going into the n75 valve. check to make sure all the pipes are connected properly.
you also mention is has a dump valve fitted? are you sure its not a recirc valve matey?

 

[Callumc]

This has been an ongoing problem since 2009. It was fixed somehow when my brother fitted an mbc. it has been garaged for 2 years and the problem is now back. on 2009/2010 it was taken to a very good garage and they were puzzled as to what the problem was! Its a forge dump valve mate

 

[cus]

mbc is gonna be the problem imo. get a new n75 put on.
i was always under the impression that the ECU/map controls the boost pressure..? unless a MBC is required, its best to stick with the n75 .

or i could be talking out of my ar*e lol

 

[Callumc]

Someone on here told my brother an mbc would turn the boost down. I think the boost may be to high on the ecu and cant be solved without a new remap. I was thinking about a new n75 but i only fitted one a month ago

 

[daz69er]

i thought if u have manual boost controller it by-passes the n75 valve well mine has :/

 

[cus]

yeah it does bypass it. you would take the n75 valve off to fit the MBC.
i personally think that unless required, put the n75 back on and get it remapped to what the car 'should' be running to.
if you find that it is over boosting, then maybe check the maf sensor or for air leaks etc. ?

 

[ibizacupra]

log 115 dude with vcds.... see if actual boost request is low and by how far actual deviates from it

if someone had added more preload to the actuator rod for example it could cause this deviation.
+/-250mb is sufficient deviation from request to cause limp...

cr4p map also can cause this too mind you

check actuator by unplugging n75 electrically and it should run 5psi.. if its a lot more this is your issue..

vac leaks also the enemy soo sooo often on these

 

[brad1002]

Bill, I unplugged my n75 on my lcr and went for a drive, it goes to 6psi the when I it get up the revs get to 15psi at about 6k. Is this a sign of actuator Faulty? I'm having over boost problems.