02 TA idle problem

[bigbucks39]

all i have done to my car is 92 mm intake/TB, headers, 2400 stall converter, and stage 2 trans. everything else is stock the tune is pretty much stock as well. i have this problem when im slowing down sometimes where the car just goes dead, the idle slows down like normal and then goes under 500 rpm and quits sometimes it will revive it self sometimes it wont. so can anyone take a look at my tune and tell me if maybe there is somthing i didnt do for the stall converter. and any other pointers would be awesome. thanks in advance.

[bigbucks39]

uhhh.. anyone??

[WeathermanShawn]

I would approach your idle problem with the same methods used in tuning a car with a bigger cam. Obviously, your airflow requirements must have changed.

There are some great tips in the 'idle tuning' tutorial found in the 'stickies', but here is a synopsis.

1). Are you now overly rich upon startup? (stock VE).
2). Double-check your desired airflow. Might need more.
3). Utilize some of the tutorial tips concerning the learned airflow corrections.

You might just try adding some air via the desired airflow table.

[Goldfinger911]

In looking at your tune... who messed up your Throttle Cracker and Follower tables? I would start by trying the stock tables then make slight adjustments from there based on idle down and deceleration behavior. Get those tables close, then go through the RAFIG or RAFIN process as well as get your VE table tuned properly. Especially around the idle area in the table.

[bigbucks39]

i didnt mess with any of that stuff but ill look into it thanks

[bigbucks39]

i just looked at all the throttle cracker and follower tables and they are the same as the tune that the car came with when i got it. if that is wrong can someone send me a tune to know what its supposed to look like. thanks

[Doc]

Did you use the FAST valley cover button head bolts? Did you employ the stock torque pattern and spec for the intake? Is the MAP sensor fitted secure?

[WeathermanShawn]

As outlined in the idle tuning tutorial, in addition to airflow adjustments, there are several tips concerning spark. In addition to the idle spark underspeed and overspeed tables, I have made the timing at rpms (400rpm & 0) higher than the idle rpms ( base spark). If it is a spark problem related to idle, as your rpm's drop and your spark increases it prevents spark from dropping further.

You could always P.M. SSpdDmon. He might tell you to apply the idle tutorial tips first, but either he or someone else might catch something else in your tune that is causing you problems. Other than a vacuum leak, those are my suggestions.

[Goldfinger911]

Ditto. Weatherman has excellent advice. You can PM SspDmon. He also wrote some excellent articles on idle tuning. I would use his advice, but start from using stock tables. Not a stock tune!! Use your tune, just replace your cracker and follower tables with the stock ones. Stock tunes can be found here:

http://www.holdencrazy.com/EFILive/stockTunes.php

SspDmons article can be found here:
http://forum.efilive.com/showthread.php?t=4661

Is your car cammed? If you want to see my tune, let me know. Nothing about my motor is stock except the block... but it idles great, and never stalls. Keep us posted how it goes.

Lastly, you also need to get that Desired Airflow at Idle set properly. Or at least close. This thread outlines how to do it. Thanks to SspDmon yet again. :)

http://forum.efilive.com/showthread.php?t=5035&highlight=RAFIG+process

[bigbucks39]

ok so i have 4 different tunes open and im looking at all the cracker and follower tables. the automatics are different from the manuals. so far i havent found anything different from the stock settings to my tune for the automatic cars. my head is starting to spin a little bit. im pretty new to this still im looking into all the idle tuning thanks for the help and opinions

[Goldfinger911]

My bad. I was comparing against other 12212156 OS's which were all Manual cars. You are correct... your tables are stock. The fact still remains that you need to ensure Desired Airflow is set correctly, as well as add some airflow to the Throttle Follower, and possibly the Throttle Cracker as well. For example, the stock tune has the TC table zeroed from 19kmh and lower, in the 1000 and 400rpm cells. I would try adding some airflow to the 13 and 19kmh cells and see what the effects are. You can log TC and TF airflow and then try to make it stall... then look which airflow is zeroing out when the stall occure. If you are on the gas, it isprobably TF. If you are off the gas, it is probably TC that will need a little more. Read SspDmon's article. He makes refernces to both and automatic cars I think.

[5.7ute]

I was having a similar problem with my cammed M6 car that occasionally when coming to a stop the engine would stall. The fix in my case was a small increase in throttle cracker airflow and slowing the TC decay rate in the low speed areas. What this does is act like a cushion for idle & will prevent the idle speed from dropping too fast.