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n75 and reason for poor turbo boost???

22812 Views 7 Replies 5 Participants Last post by  Two Mikes, 
I
Hy

I have a toledo 1.9 tdi 90 PS 1999 , golf IV platform offcourse :D

My problem is that my turbo boost is not good. Overboost is 0.75 and max longer pressure is 0.6

Standar boost should be 0.85 for my motor and my is chipptuned and should go arroun 1.1 to 1.2

Maf is good, and today i disconnected two hosses from n75 (red on the pic) and my car boosted like crazy, boost jumped to 1.7 with no problem :D

I didnt drive arround like that a lot but car was going as it should until 130 km/h and then safe mode, no over 0.6 :D

Turn off car, turn on and power is here again :D

Then i connected back hosses and now i got no strenght or boost again :(

What do this hosses do and why am i lossing boost when they are connected.. What could that be

Thanks

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R
Did you ever remove them? Maybe you connected them backwards? I bet there is a leak somewhere on the vacuum hoses or the N75 valve is bad. Try removing the N75 and cleaning it with carburator cleaner and then WD-40. It could be bad.
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rsdi4 said:
Did you ever remove them? Maybe you connected them backwards? I bet there is a leak somewhere on the vacuum hoses or the N75 valve is bad. Try removing the N75 and cleaning it with carburator cleaner and then WD-40. It could be bad.
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yes, today i removed them completly from n75 (hosses) and then car has full boost. I would like to know if anyone had similiar problem, faulty n75 or hoses. will clean it tomorrow, tnx
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B
Probably a bad n75 or wires. Do you have an EGR solenoid that you can swap it with? Don't know if your car has the same equipemnt as US cars.
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BMWnugen said:
Probably a bad n75 or wires. Do you have an EGR solenoid that you can swap it with? Don't know if your car has the same equipemnt as US cars.
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i guess egr solenoid would be a thing left from n75, similiar loking, also with vacum hoses?

i just swap them or should i make some other adjusments to fit it?

i think is has the same equipment
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chittychittybangbang
North American 90hp TDI are equipped with a N75 solenoid that can be swapped with the EGR. It looks like you have the older style N75 - on USA mk3 TDI, the EGR and N75 are totally different. If they look similar on your car, try swapping them. I don't know what it looks like on yours.

To be certain, try reading this article:

http://www.myturbodiesel.com/1000q_how_to/multi/limpmodetdi.htm

You do need a vag com (now called VCDS) to test some things but try as many tests as you can now.
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rsdi4 said:
Did you ever remove them? Maybe you connected them backwards? I bet there is a leak somewhere on the vacuum hoses or the N75 valve is bad. Try removing the N75 and cleaning it with carburator cleaner and then WD-40. It could be bad.
Click to expand...
mine are totally different :(

when i unplug both of the hosses on the left, i get big boost, when i plug them back i get 0.6 max... is this becouse of bad n75 or bad hosses
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T
definitely a sensor or solenoid problem, if you are getting boost problems but it's otherwise normal, sensor or solenoid problem, you confirmed the other vac lines too
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