Brake Torquing and Idle issues

[mini zilo]

When I brake torque up to about 3000 RPMs, if I let off the gas, the cars idle drops extremely low and the car almost dies. Is this normal? I thought it was due to a boost leak but I fixed it and it still happens. When I brake torque normal and just let the brake go, it all works fine. But if I stall up, and then release the gas, the car drops down to around 400 RPMs.


Is this normal??

 

[ypnas777]

Mine does the same thing.

 

[mini zilo]

Here is a video of mine when it does. You guys tell me if the same thing happens.


<embed width="448" height="361" type="application/x-shockwave-flash" wmode="transparent" src="http://vid97.photobucket.com/player.swf?file=http://vid97.photobucket.com/albums/l229/dmc0162/MVI_8609.flv"></embed>

 

[Geezus_Aach]

yep, mine does that too...

 

[kiggly]

This is normal. It is because the factory ECU uses an airmeter that experiences reverse flows when you let off the throttle. The intake tract and intercooler system has to depressurize as you let off the gas. Some air flows backwards out the airmeter, some gets consumed by the motor. The ECU has no idea how much air is actually going into the motor at this point. Mitsu added in their 'airmeter reset' line on 1g's to hack around this deficiency. It pretty much just puts fuel in for an approximate idling condition when that function is activated (when you lift throttle like this).

This problem is intrinsic to any draw through airmeter setup. I honestly have no idea how it could pass emissions like this. You will see the same thing happen when you go from WOT to mid throttle.

Kevin

 

[oldman]

Did you stall out trying to do a BOV salute to impress some chick?

Kevin, congrats on the 9.096. Let's see that 8sec slip soon.

 

[mini zilo]

Did you stall out trying to do a BOV salute to impress some chick?

Um. Alrighty then...

 

[oldman]

Um. Alrighty then...

Relax, it was only a joke. Plus I can't think of any situation where you would run into this problem except doing a BOV salute in the parking lot.

 

[mini zilo]

Oh, . No it actually happened to me while I was brake torquing to see how high my stall could go, and when I let off it just dropped.

 

[oldman]

I tried to do a BOV salute with my AT 95' on my driveway after reading this thread just to see what happens, car died.

 

[1stGenGSX]

mine does it to, i thought it was a boost leak at first but it still does it.