Mega overboost then finally limp mode

brad1

Guest
Evening all

Ive had this fault code come up

17965 - Charge Pressure Control: Positive Deviation
P1557 - 35-10 - - - Intermittent

Seat Leon 1.9 TDi 110 (ASV engine) with a pd130 turbo

I searched and found lots of info, but couldnt find anything like what im getting, so this is why im posting :)

Basically when the oil temp is like reasonable temp like 70-90c the turbo doesnt overboost high, will overboost to like 23psi and drop down to 20psi, but the more i give it a thrashing, keeping racing, on private road of course lol, the hotter the oil gets on the gauge, the more it overboosts and holds overboost for longer during gear changes, when the oil is very hot i have seen the overboost spike to something ridiculous like 35psi when the oil is like 120c and it holds so i have to take my foot off the throttle, then after a while of thrashing and its overboosting it will chuck it in limp mode, but its weird, the hotter the engine gets the higher it overboosts if you get me, could this be because i have a side mount still, if i get a fmic will this keep the oil temps down and stop the turbo overboosting mega like this?
any help much appreciated
 

brad1

Guest
It's had a new maf, map and n75 within the past 3 months. I'm thinking maybe sticky veins, if it was to be this do you think AmD would be able to clean the turbo up themselves like others on here?
 

volvic

It's just water
Jun 28, 2008
791
0
House of Batiatus
i dont think a front mount would affect the oil temp that much would it? maybe slightly as the air would be cooler in the engine...

underneath the drivers seat (under the car) there is a cooler.... cant remember if thats oil or diesel?

does the PD130 even have an oil cooler?
 

brad1

Guest
i dont think a front mount would affect the oil temp that much would it? maybe slightly as the air would be cooler in the engine...

underneath the drivers seat (under the car) there is a cooler.... cant remember if thats oil or diesel?

does the PD130 even have an oil cooler?

Mine is a 110 non pd with a 130 turbo on it, like I say, I've seen the oil reach near enough 150c surely that's too hot, could a shagged oil cooler cause the oil to heat this much and after time chuck it in limp mode and cause this overboost??
 
Last edited by a moderator:

air121005

Active Member
Sep 28, 2006
1,609
6
Worcestershire
i dont think a front mount would affect the oil temp that much would it? maybe slightly as the air would be cooler in the engine...

underneath the drivers seat (under the car) there is a cooler.... cant remember if thats oil or diesel?

does the PD130 even have an oil cooler?

diesel cooler is located under the drivers seat ;)
i'm fairly sure :think: as its never been mentioned before, the ibiza doesn't have an oil cooler :no: on any of the PD TDi's. wasn't aware the Leon had one either:confused:

as for oil temps of 150c :wtf:, isn't that dangerous to the engine:confused:
surely if the oil is that hot the engine must be as hot :shrug:
 

brad1

Guest
I heard the cooler below the drivers seat on the underneath of the car is a fuel cooler, but i would like to know where the oil cooler is, also if its shagged, how much for a new one roughly on a non pd 110??
 

brad1

Guest
Brad, you need a 3bar (300kpa) map sensor to stop your car going into limp mode!



Greets, Alex

Please explain further mate lol, but it still shouldnt be mega overboosting like this, 35psi when the engine is hot :(
 

majesty78

Active Member
Oct 6, 2008
490
2
Austria
Overboosting in general is a mapping failure (when you are sure that your hardware is ok) , and if you far exceed the bandwidth of measurable boostpressure of your stock map sensor you get limp mode.
You get the higher overboosting because the hotter oil lets the turbo shaft spin easier/faster
There are 2 things to do:

1. Get the correct map sensor and
2. Find a tuner who is capable to CORRECTLY change the neccesary mappings to have correct boost level

In common: Overboosting issues show poor pre control mappings depending your turbo.

Greets, Alex
 
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jonjay

50 Years of 911
Jun 27, 2005
5,843
1
Essex
Overboosting in general is a mapping failure (when you are sure that your hardware is ok) , and if you far exceed the bandwidth of measurable boostpressure of your stock map sensor you get limp mode.
You get the higher overboosting because the hotter oil lets the turbo shaft spin easier/faster
There are 2 things to do:

1. Get the correct map sensor and
2. Find a tuner who is capable to CORRECTLY change the neccesary mappings to have correct boost level

In common: Overboosting issues show poor pre control mappings depending your turbo.

Greets, Alex
Dont agree at all its the mapping as his car has been fine since he had it done a month and a bit ago.

Overboosting can happen from a faulty wastegate, split vacuum hose, possibly a faulty turbo....
 

brad1

Guest
In all fairness maz the map is a excellent map, **** hot map actually, personally I don't think it's mapping issue, it has done this the whole time this turbo has been on but only hit limp mode once and I am starting to worry more about the continuos high overboost when it is hot during gear changes
 

majesty78

Active Member
Oct 6, 2008
490
2
Austria
Dont agree at all its the mapping as his car has been fine since he had it done a month and a bit ago.

Overboosting can happen from a faulty wastegate, split vacuum hose, possibly a faulty turbo....



You should read what i wrote...
 

jonjay

50 Years of 911
Jun 27, 2005
5,843
1
Essex
In all fairness maz the map is a excellent map, **** hot map actually, personally I don't think it's mapping issue, it has done this the whole time this turbo has been on but only hit limp mode once and I am starting to worry more about the continuos high overboost when it is hot during gear changes
The map is good but the requested and actual are consistant. Your problem happens when engine overheats or something starts going wrong else where....Anyway i dont claim to be an expert I just give opinions.

You should read what i wrote...
Make me believe it....
 

AJBrunt

Guest
*sigh*

You honestly should read what Majesty78 wrote

Now, read CAREFULLY

this is NOT a MAPPING issue. You just don't have the right map SENSOR for the ecu map.

So you may have the greatest tune in the world but it isn't responding properly because of an incorrect reading from a sensor.

Please replace with a 3Bar before you go saying that this theory is wrong


BTW a split boost line will not cause overboosting. PLEASE explain to me how if you have a boost leak you can over boost?
 

brad1

Guest
But will a 3bar map sensor stop this massive boost spike when changing gears?
 

n11tht

Active Member
Mar 17, 2009
278
0
under the bonnet
But will a 3bar map sensor stop this massive boost spike when changing gears?

This maybe the most stupid question of all time, but where is the best place to get a 3 bar map sensor? is it just the standard one that you can get from a stealer? Thanks