Idle Adjustment, fans and things.

[curtbriggs]

I just installed LT headers, no cats, Z06 manifold and a 224* 112* 0.580" cam. The idle speed is about 750 RPM and lumpy with engine rock. In the Scan program 850 to 900 RPM was an improvement.
In the car, with Tune, I down loaded my current PCM calibration, opened the file and opened idle, desired idle speed. The window has four columns, the two on the right were all zero and looked like the correct ones for my 6mn. I inserted 900 RPM for the current OAT.and interpolated for the seasonal temperature range where I live. Since I lost control of the fans due to the overheat warning yesterday with the old EFI program, I also reprogrammed the fans. I changed the #1 fan on to 184*F and off to 194*, #2194 & 185* since I have a 160* thermostat. There are many choices in the fans column, I only changed the on and off of 1 and 2. Is this correct?
I Programed the PCM with the changes with a "Test" first then programed. The fans now come on at the temperatures I changed to, but the Idle didn't seem to change to 900 although it was slightly higher. Should I try the idle with Scan as on page 130 to see what works and then go back to Tune with the results? I've read the other idle threads and may try the "jfpilla" method when I get more experience. Please, am I on the right track, mistakes??? what else can I do?
Thanks, Curt

[curtbriggs]

Sure could use some help on this. Why doesn't "Tune help" explain how to correctly set the idle speed and explain the idle selections in the Navigator? Scan help has more info but still doesn't fill in the blanks.
In the Air Force, we had an old saying, "You can't go unless you've already been", that's how the help section makes me feel. I've looked at the "more info" windows, these seem to give better info, but I can't pull them up with out being connected and I don't have my printer in my Vette.

How are the rest of you solving these problems. I have a binder with about 300 pages from help. I sit in the car with my lap top and the binder trying to sort through the multi choices that aren't covered.

Curt

[bink]

Idle speed - those are engine coolant temps (ECT)...as the car heats up from cold. You want to populate (only) the "In Gear" column. Park, Neutral - leave as zeros. You may want to start at 1000 RPM cold and work down to 900 RPM at running temp - 80*C and up.

Fans - what temp thermostat do you have??
I have a 160* T Stat and my fans are at :

1st Stage On-185*F
Off-180*F
2nd Stage On-194*F
Off-185*F

My Stock 2001 TStat (C5):

1st Stage On-229*F
Off-222*F
2nd Stage On-239*F
Off-230*F

Hope this helps some.
Cheers,
joel


Oh- I see you have a 160 TStat!

[curtbriggs]

Now that makes sense, ECT not ambient. OK, I'll try that, I just set the idle again starting at 1000 RPM but didn't get high enough in the temperature range.
Correct, my thermostat is a 160*. I set the fans at what my Hypertec had them set at, seemed to be a good setting.

Joel, thanks for the help.
Curt

[curtbriggs]

I just came in from my shop, your explanation worked perfectly. I now have a 900 RPM idle at all temperatures which for now is perfect. With no Cats, it smells and acts Fat. At WOT I was getting down to 11.8 to 1 on my Innovate LM1. Now to learn the AFR matters.
I really appreciate your time and help.

Thanks again, Curt

[bink]

You're welcome.
Even lean it will smell Rich when catless. Nature of the beast ( and Unleaded Fuel).

Cheers,
joel

[dfe1]

Your 11.8:1 air/fuel is a result of the Converter Overtemp being enabled. Go to Cat Converter under Engine Calibration, Fuel, and disable Catalytic Converter Protection. The system is designed to keep the converter from excessive temperature by adding a bunch of fuel. It's difficult (maybe impossible) to keep WOT air/fuel ratios in the 12.5-13:1 range unless Converter Protection (also called Converter Overtemp) is disabled.

[curtbriggs]

Your 11.8:1 air/fuel is a result of the Converter Overtemp being enabled. Go to Cat Converter under Engine Calibration, Fuel, and disable Catalytic Converter Protection. The system is designed to keep the converter from excessive temperature by adding a bunch of fuel. It's difficult (maybe impossible) to keep WOT air/fuel ratios in the 12.5-13:1 range unless Converter Protection (also called Converter Overtemp) is disabled.

dfe1, I did all the above, I'll check AFRs tomorow. Thank you very much for the help and adding to my learning curve.

Cheers, Curt