My 95Z 28 m6 will drop from 1k to 500rpm or less randomly, it will go a month without this happening somtimes, then it might happen 4-5 times a week. Doesn't seem to make a difference whether the A/C is on or not. I've never allowed the car to die (because I'm in traffic) so I'm not sure if it would or not, I just start blipping the throttle to keep it running. When I rev it to keep it running, it rev's up perfect without missing, and I can launch it, and it has the normal amount of power. Any ideas?
The car has a mild comp cam. CAI, !Cat, !muffler, TB bypass... 255lph walbro..
The only problem I've noted with the car while on a scanner.. is at WOT it retards the timming up to 10 degrees. but at idle it does not.. so probably not related..

 

Sounds like you need a Computer Tune from www.madz28.com.
Hopefully "madwolf" from madz28 willreply soon.
I personally think you need to bump up your idle a bit.
Also check your IAC, and your Air Intake System for any leaks

 

Possibly.. I have a set of headers I was going to bolt up this weekend.. I guess I'm pushing the stock timing quite a bit.. It might be an intake leak.. becuase I made the intake.. out of exhuast tubing ect. I'll look into that

 

Could probably use some tweaking on the iac and maf. Bryan at PCM for less got mine pretty much dead on.

I idle at 650rpm with my ccc306. Almost as soon as I push in the clutch it drops to that and stays there.

A cheap tune won't hurt, but check your IAC motor. Maybe clean it if it hasn't been done in a while. (Usually revs up not down though I thought....)

 

Could be your cam. What size is it? My car does the same thing when it's a hot day out. Soon as the weather cools back down she idles fine.

 

clean your IAC


Brad

 

Like posted before clean the IAC, an check your TB fins for buildup and see if they are sticking this happened to me there was a load of carbon buildup and my idle was terrible but only sometimes. Ive heard of problems like this when people have de-screened their MAF too so if you did make sure somethin isnt stuck to it that got through the filter. Just possibilities, im not saying any of these are your problem. Goodluck

 

MAF still have the screen.. I can't remember the specs on my cam.. but it's just a little more hot than the LT4 hot cam (when you consider the proper rockers) I"ve never cleaned the IAC.. and don't know how to.. anyone have a link? Also.. someone mentioned their car has a aftermarket cam and does this on hot days, That's def. true for me too, it seems to occur more often on HOT days, and my car generally just runs porly on hot days, the hot hotter the temperature gets on my car, the more it starts to hesitate.. It's almost like it "loads up" with fuel.. while idleing.. but I never get any black smoke.. but... I think if it idled for a long time without getting over 190 degrees, I don't think it would hesistate. (sorry this is long and incoherent)

 

could my air foil be causeing this problem? doesn't it cover the hole where the air is supposed to go in, which is controled by the IAC?

 

and.. what are Throttle body fins?