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sierrafery
20th June 2019, 03:42 PM
Hi all, i need some help... is it possible to loose boost at one of the exhaust or inlet manifold gaskets? if yes how can i check that?... I checked various data logs from mine with 3 different remapped chips(one from Alive which works the best), also with a stock non-remapped ECU and i'm sure it's not management issue cos all the readings are OK except the MAP which doesnt exceed 206 at 96 AAP reading but what ever i do i can't get more than 1.1 bar boost even with the pipe to the wastegate actuator clamped, i know the turbo spins fast cos the MAF exceeds 680 under heavy load(not a factor as mine is Eu2), new genuine MAP fitted last week and still the same....the intercooler was also pressure checked and no leak, fuel pressure in the FPR 4.1 bar, turbo was replaced bran new 3 years ago and it has the uprated hybrid billet chra in it + silicone hoses so it should boost the sh*t out of it(which it did at the beginning)... this thing didnt happen suddenly but get worst in time, i observed that on the EGT gauge as it became higher under load within a month then i checked the readings and realised the lack of boost. i've checked everything which is in my power and knowledge but it's doing my head now...What am i missing here? Should i get both manifolds skimmed? Any other sugestions please?

Kaaaiju
20th June 2019, 04:00 PM
what about fuel pump or fuel related issues?

onebob
20th June 2019, 04:22 PM
Look at the boost modulator to boost pipe hose - i have had one split at onetime and “bleed off” boost.

alien
20th June 2019, 06:09 PM
Bypassing the modulator would be my first step.
Then check the clamps on the intercooler hoses aren’t loose allowing boost to be lost.

sierrafery
20th June 2019, 06:21 PM
Thanks guys,
what about fuel pump or fuel related issues?
i checked the pressure in the FPR and i have 4.1 bar in the FT sensor's port

Look at the boost modulator to boost pipe hose - i have had one split at onetime and “bleed off” boost.

Bypassing the modulator would be my first step.
Then check the clamps on the intercooler hoses aren’t loose allowing boost to be lost
i'll check the pipes attached to the modulator cos those were neglected... eventually bypass it, i'l report with the results , if there are any other ideas keep posting them

Cheers

discorevy
20th June 2019, 09:49 PM
as well as the above
If the exhaust manifold is leaking you'll see soot around the ports
If the intake is leaking you'll see oily residue around the ports ,unless you have a provent.
try tightening the bolts as sometimes they come loose.
Is the wastegate actually closing ?
Is 96 AAP normal for your altitude ?
Seems odd that the maf is maxing out with low boost .

sierrafery
20th June 2019, 10:06 PM
I hope that the wastegate is closing internally cos the arm is free. The AAP dropped to 96 from 100 under heavy load cos there is a lot of sucction through the MAF just that the boost doesnt get into the engine ... i watched with endoscope and now i'm almost sure that the inlet manifold gasket is leaking cos all it's bottom side is gunked up around the ports... i ordered new gasket and the whole package of bolts, studs etc, i'll report back with the result. Thanks

twr7cx
22nd June 2019, 09:13 PM
Whee are you measuring your boost levels? Might be worth measuring from post turbo, pre intercooler (I think the metal pipe has a nipple on it that could be used?) and from the inlet manifold (drill and tap) to compare the differences.

sierrafery
2nd July 2019, 09:10 PM
FIXED... what i can't understand is how the heck this intercooler has passed the pressure test ??? http://www.thed2boysclub.co.uk/images/smilies/icon_wtf.gif i suspect that the guys who did that just took my money and did nothing http://www.thed2boysclub.co.uk/images/smilies/action-smiley-047.gif ... i'll never rely on others than my mechanic who insisted untill he found what's in the pic... 10 years old performance intercooler(Britpart)... they welded it for now cos i need the vehicle but i've ordered a new Serck one which will be fitted next week, at least i have a new inlet gasket too... it seems that the uprated hybrid turbo billet chra is doing it's job as long i've got 1.1 bar boost with that crack http://www.thed2boysclub.co.uk/images/smilies/icon_cool.gif

https://i.postimg.cc/0yN8JVnz/Cracked-Intercooler-2.jpg

discorevy
2nd July 2019, 09:42 PM
FIXED... what i can't understand is how the heck this intercooler has passed the pressure test ??? http://www.thed2boysclub.co.uk/images/smilies/icon_wtf.gif i suspect that the guys who did that just took my money and did nothing http://www.thed2boysclub.co.uk/images/smilies/action-smiley-047.gif ... i'll never rely on others than my mechanic who insisted untill he found what's in the pic... 10 years old performance intercooler(Britpart)... they welded it for now cos i need the vehicle but i've ordered a new Serck one which will be fitted next week, at least i have a new inlet gasket too... it seems that the uprated hybrid turbo billet chra is doing it's job as long i've got 1.1 bar boost with that crack http://www.thed2boysclub.co.uk/images/smilies/icon_cool.gif

https://i.postimg.cc/0yN8JVnz/Cracked-Intercooler-2.jpg


wouldn't have thought a pressure test was required to diagnose that, with the amount of gunk around the split. I'd be getting my money back .
A good fart as a pressure test would have found that

sierrafery
2nd July 2019, 10:57 PM
The intercooler was not removed from the vehicle untill now, they said that pressure was applied to it in situ [bighmmm] ...schmucks, i'll pay them a visit with the intercooler after it will be swapped and have a "friendly" chat