2G Base Idle tune Running lean

[Potenze]

So I got my 2g running, if anyone remembers my first post (rebuilt the evo III big 16g, New timing kit).

But I had/have fast idle and an idle surge, so I replaced a bunch of vacuum lines, EGR gasket, and the IAC motor (old one had a bad coil). At the same time I adjusted throttle cable and my TPS to ~.6v (my multimeter is crap). Now it idles at 1000RPM with the BISS all the way in with a little surge 100-200rpm, so i figure I'm leaking air from somewhere but would this also make me lean out?

I have an AEM A/F ratio gauge don't, know what wide-band its connected to, But at idle it reads at ~14.5-15.1, but when I open it up it leans all the way out by ~4500RPM. Before this it was pulling like mad, and held strong all the way to 7k.

I also have another issue, does anyone know what actuator came with an extremePSI evo III big 16g? Cause with my MBC all the way down it still spools to 20PSI and I'm not sure how much this engine was built up (it has a 6bolt bottom end).

 

[jed344]

A/F sounds fine for idle as far as the 20psi that sounds high for just waste gate pressure.

 

[Potenze]

A/F sounds fine for idle as far as the 20psi that sounds high for just waste gate pressure.

Yeah it seems high to me as well, I heard that they can have a 19psi actuator, But I don't know which one they get loaded up with from ExtremePSI.

Can i test to see if its my MBC that's bad, by deleting it out of the loop? aka run a vac line from the j-pipe directly to the actuator?

 

[sRtNeOn]

Yes you can run a vac straight to the wastegate to run wastegate boost. The idle afr's are fine. You need to do a boost leak test. 20psi on the stock fuel system will make it lean out. I wouldnt do anymore WOT pulls until you get everything figure out.

 

[Potenze]

Not running a completely stock fuel system there's a walbro in tank, and 550cc injectors in the stock fuel rail, but still running the stock Fuel pressure regulator. Would a venom fuel rail and an aeromotive fuel pressure regulator help out? Would it allow me to run any richer? I really feel un-easy running so lean.

 

[sRtNeOn]

What are you tuning with?

 

[Potenze]

What are you tuning with?

Luck, I have no tuning equipment, the car came with a faulty A'pexi SAFC II, which had to be removed cause it was blocking signal from the maf to the ecu.

 

[snowborder714]

That's a horrible approach. Either get a tuning device or swap out the injectors for stock ones.

 

[sRtNeOn]

I can't see how it's even running as good as you say with 550's and nothing to tune with. Dsmlink does wonders.

 

[Potenze]

Its not really an approach, this is kind of an oxy-moron in this specific case, and may not even be possible, but i want to sure i can pass smog before i dump a ton of money into this car.

I have no doubt that it will be one of my favorite cars, and would like add dsmlink, and all the goodies, but I cant afford to just throw money at it, and i have to make sure I understand everything that i do to it.

On another note, with dsm link, from what i understand I need a 95' dsm ecu correct? and it cant be a 420a ecu either?

 

[92AWDHX40]

You need a eprom ecu or have it converted never heard of a 420a ecu being converted, i could be wrong though.

 

[Potenze]

You need a eprom ecu or have it converted never heard of a 420a ecu being converted, i could be wrong though.

What do you mean "converted" I'm new to DSMlink, but I am very confident with a soldering iron.

I'm just wondering cause theres a 2g down at my pick and pull but i think it might have had a 420a in it.

 

[OLDGREG]

What's the proper idle for a 2g?

 

[Potenze]

What's the proper idle for a 2g?

Its Supposed to be 750rpm, heres a pretty good video for adjusting your base idle correctly.

JafroMobile's base idle tuning

to do the Throttle position sensor, you want to probe the #2 and #4 wire with a multimeter and watch the voltage.

 

[snowborder714]

The ECU has to be either a '95 EPROM ECU (which can be socketed to accept the ECMlink chip) or a '96/'97 non-EPROM ECU (which ECMTuning will convert to EPROM to accept the ECMlink chip - you can't do this yourself). Any other ECU will not work.

 

[Potenze]

So last night I took my SAFC II apart and found a mass amount of gunk it it, after cleaning it out it worked like a charm.

But it didn't fix my issue my current tune looks like this.
RPM 800 1800 3000 4000 4400 5000 5400 6000 6400 7000 7200

Hi -21 -28 -34 -38 -44 -48 -50 -50 -48 -46 -44

~AFR 14.8 15.0 13.4 12.1 11.8 10.5 10.2 10.2 10.2 10.4 10.6

Low throttle seems fine, but even with the safc pegged i cant get rich.

And currently the waste-gate acuator is hooked straight up to the j-pipe so i think that my wg actuator is either dead or its a 19psi actuator. either way i think this means its time for injectors but im more likely going to try and find a different wg actuator. really that's my only option at this point right?

 

[ennioGST]

find yourself am evo 8 ecu. i got one for 200 bucks ### my ecu was not flashable. it worked great have a solid tune.