Flat Spot ?!?

[Havok316]

Can anybody tell me what a flat spot is? I dont think ive ever experienced it. Is it when you presh down the accelerator the car feels like its not going any faster for a short second or two then kicks in? Also what causes a flat spot?

 

[Funkyfin2000]

mine does that everynow and again, i think that more to do with the N75 valve...

i can floor mine at high speed it will not do anything and then suddenly surges forward

 

[Havok316]

ah right i see might have to do some logging cheers

 

[G2232]

flooring it at high speed and experiencing a "surge" i would say is more turbo lag than a flat spot.
a flat spot i would explain as accelerating turbo kicks in then eases off or holds before climbing again.

I could be wrong though

 

[Hicks]

I know exactly what a flat spot is, because mine does it right now. I can put my foot down in 4th gear and get no boost. The car just refuses to accelerate. I did change the N75 a couple of weeks ago, but it's still doing it.

 

[Funkyfin2000]

yeah thats what i mean, u put ur foot down and nothing happens and then the power suddenly surges in!

 

[G2232]

but if nothing happens immediately thats turbo lag not a flat spot

 

[Havok316]

Im getting it in 1st/2nd gear when i accelerate i feel the car not accelerating and it feels like the car is pulling pack and i can feel myself moving forward on the seat. doing 20mph about.

 

[G2232]

yeah that sounds like a flat spot to me.
Rather than a delay and then being pined back in your seat

 

[Havok316]

So what actually causes flat spots? The n75 valve? or something like coil packs spark plugs etc?

 

[G2232]

see know thats where my knowledge actually ends in not too sure what can cause it

 

[willcooke]

A lack of power, and then it all coming in at about 3k revs was caused on my car by a faulty coolant temp. sensor.

Search for "green top coolant sensor" for details of fitting. It's a cheap part and a 5 minute job to fit.

 

[somie2k]

just want to say just read this post and checked my n75 to find out it was not plugged in a a huge thanks to all who posted about it

the smile is back on my face having gone from 4 psi to 10