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Discussion Starter #1
hi all well i would like to know if someone can explain me de differences between the soft limp mode and the hard limp mode infact before installing the n75j valve i sometime soffered from soft limp mode but after installing it i go always in HARD limp mode and the only thing that i can do to boost again is vag my car hope that someone can help me because i have a custom chip made by my mechanic and we don't know the reason i have already ordered the mbc overboost solution kit to prevent spikes but HARD limp mode is always caused by spikes or something else?
 

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Limp mode is when your boost (map) sensor sends a signal to ecu that 1.45 bar boost has been exceeded and the ecu cuts max requested boost back to basically zero, maybe .3-.5 bar. That's the only kind of real limp mode I know of. Otherwise, I think "soft" limp mode is just "car not running right", ie, timing getting cut because of fuel or ignition problems, boost loss or erratic boost because of bad DV, other boost leaks, etc.

Your new N75 is letting boost spike over the 1.45 threshold and you go limp. Same thing happened to me with K03 GIAC programming and the H valve. Fix was to go back to stock valve.
 

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Discussion Starter #3
when you hitted limp mode you had just to turn off the ignition key or to vag the car ?
 

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Vag'd it to get rid of the code, but I'm not sure it's necessary. Ignition off also works I believe, but of course if you step on it too much again, it will come right back.
 

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I noticed I am having problems, but I believe it has to do with the temp. sensor being bad......... anyway, my car went into limp-mode today, but when it goes into limp-mode is it normal when you are on the Highway, for the car to rev and not shift?
 
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