When cold/warm or whatever I'll rev the car up then the rpms will drop to like 350/400 almost die then come back to 700. Any Clues?

 

hmmm... poorly tuned ignition, perhapse?

 

naw I'm running an MSD Coil , 6AL which bypasses the Ignition module, MSD Cap rotor , new pickup coil, new wires, new plugs, timed at 6*

 

Would seem your IAC may not be operating correctly...or isn't getting the correct info to operate as you need it.

IAC should maintain the idle RPMs for all occaisions..i/e under a load coming to a stop, or winding down in neutral.

Can you scan the ECM to see what to IAC is doing? i/e the counts?

 

I have a tech 1 scanner which shows the counts. Now I have never used this feature yrt. What should it read at idle and when i rev it up and let it come down should it hit teh same count as idle or go like -2 then come to the count for idle?

 

you may want to check the fuel pressure regulator diaphram. if it's leaking the high vacuum when caused by the rev down can suck fuel passed the regulator if there is a problem with the diaphram. i've ran into this problem before. also a problem with the minimum air setting can cause problems. what is the block learn numbers showing when this happens?

 

Heres the scoop. The FP at idle is 43PSI and 47PSI line disconnected. The FP at idle used to be 38 last year but over the winter I put in a new Walbro 255 unit and the pressure seems to be higher. blm's are 126/129 idle reved up and come down are 119/135 this is after a TF head swap and a Xtreme cam. I'm running the stock chip still.

 

don't know the size of your cam but, it is idle searching. you might be surpassing the stock chip's capability with the cam. the cam too large for stock programming so it is idle searching.

 

218/224 .496/.503 .521/.528 1.6RR's and 112 LSA

 

i would say time for a custom chip myself.

 

i'd agree, that's alot of cam with a stock chip to have no idle problems. do you have any numbers with the t.p.s reading at idle and mass air flow numbers at just a normal idle?

 

I know I am surprised. In Closed loop its 128/127 BLMs Smooth idle at 750 . TPS is .54 I havent checked the MAF Yet. Its brand new but i'll get the readings tomororw. But man does it Haul.