Sputter Off Idle

[MARKO]

My 86 GN is having a sputtering problem off idle. When I leave
from a set of lights i notice it sputters or somewhat hesitates and
then it will be fine in the 2500rpm and up range. There was a
coil pack put in about 8 months ago from the previous owner.
The MAF was changed with a jobber reman by me 2 months ago
because i had high low idle problems. The car has green stripe
injectors, 260H comp cam, 3"d/pipe, 340 f/pump, adj reg. hotwire kit. Is there any way to test the coil or module? Don't want to buy
the parts and find it hasn't fixed the problem. One other thing I'm having problems with is my fuel pressure keeps cutting out
once i build some boost or once it gets up to about 50psi it just
bogs and drops back to like 40 psi. WTF. I've changed the pump,
regulator, fuel filter and checked the hotwire kit to make sure
there wasn't a voltage drop and it was fine.
Thx for any input

 

[channer]

HI,

Do you have a scanmaster or a scanning tool. Your TPS and IAC maybe out of wack. They should be...

TPS should be .42
IAC should be around 20-25

good luck... dave

 

[MARKO]

ya i got a scanmaster. My tps is .42 and my iac is 30. It's
weird, today i had no sputter problem, but the fuel pressure
drop was there. It's really annoying with the sputter cause it's
intermittent. ??

 

[WarpSpeed]

An exhaust leak. or cracked header can cause hessssitation.
Fuel pressure, take a close look at the vac hoses for leaks. Also, i've seen the metal tube that the fuel pressure regulator vac hose attaches to, clog up with oily junk, which affects fuel pressure changes from vacume to boost, etc.
Oh, the IAC works better around 12-15, in my opinion.