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Discussion Starter · #1 ·
my n18 valve is broken and i was wondering if i will be ok to use an n75 valve in its place?
 

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Now that is carbonisation.. bad design or what.. what happens when people dont know how to clean there egr pipes and jsut drive and drive and drive?
 

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Discussion Starter · #6 ·
my egr is blanked off and ive removed all the vac pipes from the n18.

my mpg has dropped tho and i wanna put it all back to check but i cant cos i snapped one of the vac connections off the n18.

i can get hold of an n75 easier so wondered if that would be ok to use instead
 

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TEAM 88 MOTORSPORT
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my egr is blanked off and ive removed all the vac pipes from the n18.

my mpg has dropped tho and i wanna put it all back to check but i cant cos i snapped one of the vac connections off the n18.

i can get hold of an n75 easier so wondered if that would be ok to use instead
Blanking the EGR will not affect your MPG...putting your foot down will[:cool:] Check your air filter, make sure its clean.
 

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Discussion Starter · #8 ·
I'll check the filter but I dond understand the sudden drop in mpg straight after the blank was fitted.

Surely the engine takes longer to warm up?

Anyway can I use an n75 in Place of the n18?
 

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Golf V R32 3.2 250PS DSG / Golf IV TDI-R 200PS
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If it's straight after the blank then you need to check a few things.

Did you fit the blank to the flexi pipe as per the instructions, or did you fit it directly to the manifold as most on here have done after finding out the hard way?

Did you seal off the relevant obsolete vac pipes or leave them in free air?
 

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You have taken the little connecter pipe off completely and blanked the two holes off haven't you? Just because if you leave the little pipe on, or don't block it at both ends it splits which might be causing your problems.

Sorry I can't help with the n75 question mate
 

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Discussion Starter · #11 ·
ok guys i blanked off the manifold and egr with 2 plates so i could get rid of the pipe between the 2 thats prone to splitting. i kept the gaskets in place under the plates.

at first the vac pipes were all left in place, then i just unplugged the wiring to the n18 valve. Then I followed a thread on here and removed the n18 valve from the vac circuit and blanked off the vac pipe to the egr valve.

all 3 of the above made no differnce.
 

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Golf V R32 3.2 250PS DSG / Golf IV TDI-R 200PS
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I didn't read this correctly at first - I thought you had put an EGR delete in and blanked off the manifold. It was only when you started talking about two blanking plates that the penny dropped.[:S]

Did you clean the EGR out before disabling it? I'm not sure if it uses exhaust pressure but if it does it will now be clogged with no way to clean itself.

Have you double checked your vac lines? The only ones you have left should be; the pipe from the tandem to servo pipe which goes directly into the black side of the one way valve (having removed the T going to the N18) then onto an optional T leading to the reservoir if you want to retain it for output tests or otherwise directly to the N75. If you imagine them as tiers of a wedding cake it would feed the top tier. The middle one feeds the turbo actuator and the bottom goes into your airbox. That's it! there should be no other lines. I would leave the electrical connections attached to the three N valves though to prevent faults.

If this all checks out and the vac pipes are undamaged then I would suggest your fault lies elsewhere.

In answer to your original question, I wouldn't use a N75 to do the N18 job IMO - I don't think they work exactly the same.
 

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Discussion Starter · #13 ·
I cleaned the egr and inlet when I blanked it.

I'll go over the vac lines again. Maybe ones split.
 

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I didn't read this correctly at first - I thought you had put an EGR delete in and blanked off the manifold. It was only when you started talking about two blanking plates that the penny dropped.


Did you clean the EGR out before disabling it? I'm not sure if it uses exhaust pressure but if it does it will now be clogged with no way to clean itself.

Have you double checked your vac lines? The only ones you have left should be; the pipe from the tandem to servo pipe which goes directly into the black side of the one way valve (having removed the T going to the N18) then onto an optional T leading to the reservoir if you want to retain it for output tests or otherwise directly to the N75. If you imagine them as tiers of a wedding cake it would feed the top tier. The middle one feeds the turbo actuator and the bottom goes into your airbox. That's it! there should be no other lines. I would leave the electrical connections attached to the three N valves though to prevent faults.

If this all checks out and the vac pipes are undamaged then I would suggest your fault lies elsewhere.

In answer to your original question, I wouldn't use a N75 to do the N18 job IMO - I don't think they work exactly the same.
I've tried it once, and it was working.
 
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