Speed density, stalling out, sick of it.

[STI 2NR]

I have a great map for my sd tune. The one problem I am having lots of trouble with is stalling out. I can replicate it everytime sitting in my driveway. I thought it was my 5-0 motorsports injectors but my new injector dynamics exhibit the same behavior.

Anyone else have the same/similar issues??

I want to fix this and have tried numerous things.

The motor will oscillate back and forth when coming down to an idle and if you blip the throttle it will go up and then dip down and die. I can replicate it while driving around. The one thing that I changed that helps a teeny tiny bit was changing the base idle ignition timing to 17 degrees flat.

Thoughts? I am on a full mafless sd tune. Car runs way strong besides this stupid issue of idle oscillation and stalling out. Happens a lot in reverse.

 

[STI 2NR]

Keep in mind that this same behavior was on my old stock motor and is the exact same thing on my new built motor. Somewhere in my tune there is something not right.

 

[STI 2NR]

No response huh? Well how about 50 bucks paypalled to the first tuner that can fix this issue for me. The issue has to be gone 100% and you get 50 bucks in your pocket. I can give you my current map and you can review it. sti2nr2@live.com

 

[Spamby]

No response huh? Well how about 50 bucks paypalled to the first tuner that can fix this issue for me. The issue has to be gone 100% and you get 50 bucks in your pocket. I can give you my current map and you can review it. sti2nr2@live.com

The boards aren't as active on the weekends. Give them a chance to get back on and see your post. :tup:

 

[Td_d]

Hey STI 2NR

There are a number of ways you can tackle this. The very first thing I would do is reduce the filtering value on engine load - if you read the write up on COBB SD, you will see what I'm referring to.

The second thing is to up your overrun fueling injector resume point up by ~200 rpms (will not deal with the idle issue, but will assist with rapid deceleration).

The third option is to create a 'bowl' of timing around your idle RPM in the base timing table, and ensure that it's not too far from what your base idle timing table is. As soon as you touch the accelerator pedal, you are shifting to the primary timing table. When stationary and neutral, the idle timing. Large differential in timing will lead to a swing.

Lastly, if you are still struggling, it's time to mess around with the idle requested torque tables - but only if you don't come right above. Try each one in sequence, and see if it helps. I'm betting 1 goes a long way.

 

[Td_d]

Oh, and by the way - if those are ID1000's, I have the low pulse width compensation calibrations for them as well.

 

[HolyCrapItsFast]

I woul like to suggest exhausting all mechanical issues first by performing a boost leak test and a vacuum test. Then I would like to see a log when this happens..

 

[fuji_production]

are you using cobb SD?

 

[Boogieman98]

I had this happen on a Ford Focus and it was a vacuum hose.

 

[STI 2NR]

Hey STI 2NR

There are a number of ways you can tackle this. The very first thing I would do is reduce the filtering value on engine load - if you read the write up on COBB SD, you will see what I'm referring to.

The second thing is to up your overrun fueling injector resume point up by ~200 rpms (will not deal with the idle issue, but will assist with rapid deceleration).

The third option is to create a 'bowl' of timing around your idle RPM in the base timing table, and ensure that it's not too far from what your base idle timing table is. As soon as you touch the accelerator pedal, you are shifting to the primary timing table. When stationary and neutral, the idle timing. Large differential in timing will lead to a swing.

Lastly, if you are still struggling, it's time to mess around with the idle requested torque tables - but only if you don't come right above. Try each one in sequence, and see if it helps. I'm betting 1 goes a long way.

I do not have a filtering value on engine load. I am using ecuflash to modify/write maps. Overrun fueling resume is already at +200 rpms. I have messed with that before and it does not help. I do not have idle requested torque tables either. I do have requested torque tables though. I swear this has to do with timing and not fueling at all. I believe you are pointing me in the right direction though. I am so sick of stalling out in reverse every single time. ARRRGGGHHH!!

 

[STI 2NR]

Oh, and by the way - if those are ID1000's, I have the low pulse width compensation calibrations for them as well.

They are in fact ID1000ccs. Those values would help me immensely. I am running them at 50psi/350kpa at idle. Getting around a 2.05ms pulse width with that fuel pressure.

My mods are as follows:
Self built block from scratch; 05 case halves, 09 heat treated crankshaft, manley turbo tuff rods, manley 8.5-1 2618 pistons (standard bore), 11mm oil pump.

Fueling: Walbro e85 465lph fuel pump, sard fpr set at 50 psi, ID1000cc, agency power 6an feed lines to t1 side feed to top feed conversion rails.

Turbo: Kinugawa TD06SL2-20g with 45mm hypergate and a 15psi spring, grimmspeed bcs

Exhaust: Fully fabbed and rotated 3" with no cat, replica hks carbon ti muffler

Electronics: GM IAT and 3 bar MAP running full speed density (mafless), netbook running windows xp, ecuflash for maps and romraider logger to monitor/log vitals

Intake/intercooler: Fully fabbed 316ss aps kit modified to fit on my setup, 30x3x10 core with auto spray to improve efficiency, 3.25" 316ss cold air intake with a high flow k&n 4.5" air filter

That's all I can think of right now. I will futz with the timing a bit when I get a chance, if it works you got yourself 50 bucks td-d. Give me some time though, I am a busy man, tuning takes time.

 

[STI 2NR]

NO mechanical issues. Those were all fixed when I built my motor.

 

[fuji_production]

damn, 465 pump? are you using romraider? so you are on stock cams?

 

[STI 2NR]

damn, 465 pump? are you using romraider? so you are on stock cams?

Yup, yup, yup. Well, ecuflash technically. Romraider has no sd table in the vagcom cable version.

 

[Td_d]

I do not have a filtering value on engine load. I am using ecuflash to modify/write maps. Overrun fueling resume is already at +200 rpms. I have messed with that before and it does not help. I do not have idle requested torque tables either. I do have requested torque tables though. I swear this has to do with timing and not fueling at all. I believe you are pointing me in the right direction though. I am so sick of stalling out in reverse every single time. ARRRGGGHHH!!

Well, you've come to the right man
I'll pull out the relevant parameters and tables for you. What you ROM id? I'm betting the engine load filter will deal it.

 

[Td_d]

They are in fact ID1000ccs. Those values would help me immensely. I am running them at 50psi/350kpa at idle. Getting around a 2.05ms pulse width with that fuel pressure.

No problem - get your Rom ID to me, and I'll pull together the required definitions.

EDIT: CAL id A2ZJBSDJ, right?

I've pulled the engine load filter definition and the low pulse width table, might be easier if you just PM me the xml file. You running the latest 32BITBASE.xml from Merp's Github repository, right?

 

[STI 2NR]

No problem - get your Rom ID to me, and I'll pull together the required definitions.

EDIT: CAL id A2ZJBSDJ, right?

I've pulled the engine load filter definition and the low pulse width table, might be easier if you just PM me the xml file. You running the latest 32BITBASE.xml from Merp's Github repository, right?

I will send those files to you in a pm on romraider since I cannot attach any files to a pm here.

 

[Td_d]

Gotcha - I've received the files, will have a look today.

 

[Td_d]

Ok, I've responded on RR - I've also edited the rom for you (and fixed your low pulse width definition, it was off, and the value as a consequence completely out). Your values were zeroed - the opposite direction to what is required (once you drop off the the so-called knee, the linear relationship between volumetric flow and pulse width in ms. breaks, so more not less compensation is required

For others interested, the values for ID1000's are (as calculated by Jason, author of CarBerry):

 

[fuji_production]

is that in ecuflash? I'm not familiar with that parameter in RR