IAC increases in drive causing very fast idle

**Motors** · 09-01-2021

Ive got an 86 Monte with an 86 Camaro TPI setup. I'm trying to figure out why the IAC goes from 60 counts at idle resulting in an idle rpm of about 800 to 160 counts when drive is selected. With the brakes held of course the idle remains 900 rpm but if I let it role the idle will go up to 1250 rpm and about 25MPH. The engine is in closed loop, operating temp. The idle speed table vs temp is a little high on the idle, 750 at 68C, but the high idle problem doesn't occur unless park/reverse is selected.

Any ideas out there would be appreciated.

Thanks!!!!

Ok so it's the 10k resistor causing some of my idle problems.... the problem however is that I loose the data steam on tunerpro as soon as I remove the resistor. Does anybody know of a reliable way to log without the 10k in place?

**NomakeWan** · 09-01-2021

https://www.thirdgen.org/forums/diy-...when-aldl.html

Bunch of info here is probably related directly to your issue.

**Motors** · 09-02-2021

Thanks for the reply! I read all of that. I'm using a $32B mask and it appears that I'm not going to get data once the 10k jumper on my cable is removed. I've tried it many times and the data stops, both in TunerPro and WinALDL. This really wouldn't be an issue if I wasn't working on obtaining a better idle condition. So I read in the link you sent about switching to a $6E mask and using a new bin for that mask and removing the 9th injector. I kinda like my 9th injector, cold start is excellant but if that's the only way to datalog a 1227165, $32B mask I guess I'm gonna have to experiment. Do you know if that's the only way to data log the 1227165/$32B in normal mode?? I'm thinking but not sure that at one time Datamaster logged data successfully without the 10k in place.

Again thanks for the reply.

**In-Tech** · 09-02-2021

The 6E has better everything, including cold start without the 9th injector being triggered. 32 and 32b is 86-88. 6E is '89. Why would you not start with GM's latest?

**NomakeWan** · 09-02-2021

Agreed. In case it wasn't clear, $6E accomplishes the same great cold start characteristics without the need of the cold start injector. It is a far more refined piece of code. If you don't absolutely have to stick with $32 or $32B for whatever reason, it's best to switch to $6E for the '165.

**Motors** · 09-02-2021

Hahha... right I need to get current!! Ok, so can you point me towards a bin and a $6E mask to get started with? 86 305 200-4R with a mild cam, stock 350 injectors, stock heads everything port matched.

Thanks

**NomakeWan** · 09-02-2021

http://gearhead-efi.com/Fuel-Injecti...ull=1#post2649

Since you're already using a Camaro TPI setup (with an automatic?) I would pick AUJN, and then modify the fuel/ignition/TCC/etc tables to match the ones already in your tune.

**Motors** · 09-02-2021

Great. I looked at Eaglemark's post on that and was thinking one of those would work. AUJN is for a 350 and I have a 305... still ok? And yes automatic 200r4 with a 3.73 gear.

**NomakeWan** · 09-03-2021

Originally Posted by Motors

Great. I looked at Eaglemark's post on that and was thinking one of those would work. AUJN is for a 350 and I have a 305... still ok? And yes automatic 200r4 with a 3.73 gear.

305 is still a V8, right? If you use your current fuel and ignition tables (and anything else specific to your setup) it should work just fine. You can't just plop AUJN in without making any changes if that's what you're asking.