siggy_freud

Howdy there people. I am writing concerning idle troubles I am having with my engine using the 6E mask. I have been doing some reading on this board about the subject. I finally cured my long crank time problem thanks to some very helpful posts, but am still having some idleing trouble when cold.

First off, this is what I have. 350 cu/in engine with a TPI using an 89 6E mask. The cam is a 224/224 @.050 - .528/.528 lift and a 112 LSA. Some trickflow 195 heads top it off. I also am using a Super Ram base (hopefully the rest will follow soon).

Now to what its doing. It now starts up and fires after 1 or 2 revolutions which is much nicer than what it was doing. However it still will die within a few seconds of starting if I dont fiddle with the gas. If I do, it will idle smoothly around 750 RPM, however anything below that and its rough until it warms up.

I have tried playing with the Idle RPM vs. Coolant Temp table, as well as phyiscally moving the screw on the throttle blades. I can seem to find a happy medium. If I adjust the blades to keep it alive during cold startup, it idles at 1200 RPM no matter that the commanded RPM via my chip is 700. If I adjust the blades (with the AB pins jumpered and then IAC unplugged as per setup instructions) so that its at 700 RPM when warm, then the idle is WAY to low to sustain itself during cold startup.

I have read some threads pertaining to this, but most concern a different mask and a Speed Density setup vs. what I am using.

Any thoughts on to what can be done? I have also played with Startup Enrichment and havent really been able to make a helping difference.

Thanks for your time,

Dylan.

RednGold86Z

iTrader: (1)

Kind of seems like your IAC isn't working. Put your hand on the IAC and feel it while someone else keys on and off. Do the other standard diagnostics on it too.

327_TPI_77_Maro

iTrader: (8)

Make your open loop AFRs a ton richer at colder temps. I had to do this with the 232@0.05 cam I was running. It was too lean and couldn't hit its target idle speed until I richened OL up a lot. You should not be playing with the idle screw. This is only used to set minimum air. You are going to screw up your IAC counts by playing with this.

siggy_freud

I played with the idle screw to see if I could get the IAC to take over. I figured if my target idle was 750 RPM, and the IAC was closed because the butterflies were open enough to allow that RPM, then as I closed the blades the IAC should start opening and take over and maintain that higher RPM. This was not the case. This leads me to believe the IAC isn't functioning. I am going to look into that first, and then look into the open loop air/fuel during cold engine temps.

Thanks both of you.

88 350 tpi formula

iTrader: (9)

I am having the same problem now that it is warmer out? (started fine when it was colder out) odd but when I first start it I am having the same problem. I tried to richen it up but I still don't have it down. funny thing though in limp mode it starts and holds it's idle like a champ! how rich should I go? o2 seems to stay around 380 -390 tops but, I may get a new one just to see

it's a 350 with a big cam heads ect ect... it has 42# injectors so should I cut all the ratios in half since it idles great with the limp home mode (since it's for 22# vs 42# I have in it = almost half?)