boost problems & N75...

[thenofjboy]

i am in the process of trying to figure out why i have a loss of boost. I replaced the tube going from the turbo to the N75 today and i went to test the wattage on the wire that connects to the N75. What is the correct number of volts that wire should be getting? Mine is around 5.31 volts. I am not sure if it should read 12v. Maybe the wires are frayed or there isnt a good connection....
Im going to bypass my N75 tomorrow and see how my boost is then.
O yeh, what are the part numbers for the 2 tubes that connect to the N75? The one to the WG, and the one to the turbo? Thanks in advance

[a4_1.8t_01]

You want people to help you and you dont even mention what car you have. Do some searching before you post non sense.

[Rico750]

i am in the process of trying to figure out why i have a loss of boost. I replaced the tube going from the turbo to the N75 today and i went to test the wattage on the wire that connects to the N75. What is the correct number of volts that wire should be getting? Mine is around 5.31 volts. I am not sure if it should read 12v. Maybe the wires are frayed or there isnt a good connection....
Im going to bypass my N75 tomorrow and see how my boost is then.
O yeh, what are the part numbers for the 2 tubes that connect to the N75? The one to the WG, and the one to the turbo? Thanks in advance

what is loss of boost? you have a gauge? how much boost does it have? do you hear it leaking? does it limp? did you check for vaccum/boost leaks first? give us some more info..

[biketsai]

You want people to help you and you dont even mention what car you have. Do some searching before you post non sense.

lol, i think they only made the b5 a4 in a 1.8t or a 2.8 v6.
I think he has the 1.8.

For the N75 valve, the longest plastic tube goes to the turbo inlet pipe. the two others go to the wastegate/turbo

[ModifiedA4]

lol, i think they only made the b5 a4 in a 1.8t or a 2.8 v6.
I think he has the 1.8.

*slap* it matters if hes DBW or not *slap*

so yeah, if he wants help he should tell us what car he driving. you'd think a "BAT" member would know this. lol.

[maxspeed]

*slap* it matters if hes DBW or not *slap*

so yeah, if he wants help he should tell us what car he driving. you'd think a "BAT" member would know this. lol.

seriously, maybe we should starft a KTU group....

"Knowledgable Turbo Users"

[thenofjboy]

sorry for the lack of information. i have a 98 1.8T GIAC chipped and some other small things.
I usually get around 15psi & everything was fine Friday but when i went to drive Saturday, that was it. I was working on my heat shield friday and was moving the air box around etc. but i checked everything all the tubes and hoses that are attached to the lid of the airbox.
Now i boost to almost 10psi. and its weird when i am in any gear and let off the throttle, the boost reads 25hg. It idles fine at around 19hg in the hose pressure. Even when im driven, the gauge reads 0 or below. i have to almost floor it to get it over the 0 degree mark. I used to be able to floor it and hit 15psi no problem. I am still boosting a little but its nothing like it was before. My acceleration is a joke ha...
I do not hear anything leaking air wise. I am going to bypass the N75 tonite and see what happens & if nothing comes out of it, im going to make that tool to test the boost pressure.

[thenofjboy]

anyone?? any comments at all are MUCH appreciated :) TIA

[biketsai]

Do a boost leak test

[thenofjboy]

im going to home depot to buy the materials tomorrow. one question though, i put the testing tool on the TIP correct? I got a little confused bc i was reading a post and somone said to put it on the turbo inlet, rather than the TIP itself....
please advise. i miss boost haha

[Rico750]

maybe you reversed the check valve above the airbox. (little valve that blows 1 way) re-check the hoses.. you must have connected something wrong.. did you reverse the N75? long sinde goed in the turbo inlet hose. Do you have a VAG by any chance ?

[thenofjboy]

maybe you reversed the check valve above the airbox. (little valve that blows 1 way) re-check the hoses.. you must have connected something wrong.. did you reverse the N75? long sinde goed in the turbo inlet hose. Do you have a VAG by any chance ?

I didnt touch anything on top of the airbox, i just flipped it back to expose the air filter. I was gentle with the tubes when i did this. And the only thing i did with the N75 is unhook the electrical connection a bunch of times (checked the wries under the rubber) & the hose to the turbo.
I also unhooked that tube on the side of the airbox that leads down to umm i forget haha not sure what that tube is for. no Vag....but ive checked alot of things - dv, boost gauge, vacuum hoses, election connection of n75 with meter and not that little tool to test the pressure. I should have done this 1st but o well i learned alot more about me B5 engine

[Rico750]

im allmost positive this is n75 related.. i broke mine once taking it out.. do you have another n75 to test?

[thenofjboy]

im allmost positive this is n75 related.. i broke mine once taking it out.. do you have another n75 to test?

I do not have one on hand. i was going ot bypass the N75 and see what happens. I tested the N75 and got 31 ohms. i think im supposed to get between 30-40. If i bypass it and boost like i usualy did, then its the N75?

[Rico750]

i think the only way to bypass it safe is with a mbc.. (and im not sure if the n75 then still needs to be plugged in to the electrical wires or not. Not recommended recommended though... but it should help you troublshoot... im not sure on the ohm's just never checked that..

to the rest: can't he not just pull the hose off the waistgate to test if he has boost?