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So, what would I need to focus on to keep the engine from bogging down and dying? Like when I'm backing out of my garage and if I'm not feathering the throttle and I turn the wheel, the car will die most of the time.
Is this an issue with A/F at idle? Or is this too low of an idle RPM? It idles beautifully and doesn't have problems like in parking lots where I am able to actually give it a little throttle. But like backing out of parking spots or my driveway where I may have to wait on someone usually results in a stall.
To many variable to nail it down to one particular cause but keep in mind that at idle your making very little power with a stock engine. Throw in a aftermarket cam and other modification and it's probably even making less at low RPMs than stock. I don't know what you're running for a cam but that would be my first guess. Easiest fix would be to bring idle up and hope that it's still low enough to not start bumping the converter.
Leaning it out at idle will help if it's running rich.
That's my thought. It's a 234/242 111, so it's pulling almost no vaccum, though I do have it in the high 60s kPa in idle. I have it set to 900 in drive, but that may simply be too low. It idles fine there until I put a load on it. I guess I should say the load with the brakes and steering will always kill it. My driveway is sloped, so I don't need to gas it to get it rolling backwards.
I have plenty of converter, so I can raise it up to 1000 or 1100 and see.
Watched your Youtube videos. Idle speed in one was around 900rpms and if that's still the case I would look at the tune. I don't think you can or would want to go any higher from there and the cam doesn't sound like it has a lot of overlap. An under drive pulley maybe? It will give you a better mechanical advantage when driving the power steering pump and alternator, The down side is the power steering and alternator won't be as effective at idle.
edit: Cooling at idle could also become an issue.
Last edited by LLLosingit; 02-03-2015 at 09:22 PM.
Here is couple of random thoughts, BRAF isn't correct, what does your STIT show when you are headed for the stall?
Idle timing is beyond best torque, so there is no reserve torque when the under speed timing table is trying to save you from the stall.
You also maybe dealing with two different situations, is it still running on the idle tables while all of this going on? Or is at times moved into the rolling tables causing issue? If it is timing during a rolling condition how are your main & idle timing tables setup in those offending area's?
I tried opening your tune file in another thread & could not. It's something how my computer wants to open the file that I have not explored.
BRAF needs to be reset because my cold idle was off due to it being rich with the Open Loop E/Q table. I was going to try to mess with it this week. May get some time today.
Idle timing is 28 degrees across the board.
I'll need to look and see what tables it is falling to, but I think it's still in the idle tables. I have the idle tables and running tables set to 28-30 in the same areas so there is no drop or weird transitions.
Hey Jake there is a torque management table that has a table for accessory load. I bumped mine up quite a bit and it did help a little. I played with timing on mine and raised the idle to 900 which was the biggest helper on mine. My 850rpm idle with a 30lb clutch setup just didnt like life. My stit's and such were all good and never went into the negative.
Another thing I did was alter the range of the ltit. I noticed on mine with the range set from -3 g/s to 3g/s after some observations of what they did during the stalls I changed them to -.5 g/s and then left the adder to 3 g/s. The ltit was subtrating air when it wasnt really needed and caused the stall. y changing he subtractor to -.5 it limited the amount that was remembered.
In the end nothing really fixed it 100% I still live with some of the tribulations of having such a light clutch. I also played with the decay rate of the follower to make it a little slower. Its not perfect but its real close.
I also happened to get a turn one power steering pump and that flows less fluid than stock ie less load and that also helped a bit
Up the RPM, adjust the values in over and underspeed idle tables to about half of stock, play with live spark settings to find the ignition that creates most torque (smallest MAP), adjust idle airflow until STIT's and spark based modifiers are more stable.
Okay. I'll play with it today some more if I get the time. I have my STITs fairly stable, but I'll play with spark and reduce it from -3 to -.5g sec. I also reduced the adjusted the over and underspeed idle to get rid of those wild swings.
I'll also look at that torque management table. It's a 9.5" billet torque converter, so it definitely is more like having a lightened flywheel. I may need to up those values.
Also, the Turn One is on my list of the next round of mods. How did that help with steering feedback? The suspension that's on here now is like whoa in how much it changed how the car feels, but was wondering if the Turn One does even more to help?
good try those and report back. I put timing at 15-30 degrees and ended up just leaving it at the stock 22 for idle since it really didn't change much. I also tried enabling the main spark table for anything over speeds of like .5 mph and .2% tps just as an experiment. That pretty much fixed it but the downside was that it wouln't enter the idle spark table while rolling causing an idle hang. I could never figure out why it did it as the parameters were being met. It seems sometimes the pcm's do things just because they feel like it lol
The turn one made the steering a little heavier in parking lots. Driving normally the steerings isnt any harder but does feel more responsive when you turn the wheel. The billet pulley looks sick though and gives access. I dont currently have a cooler on it either and the fluid doesnt ooze from the cap like the stocker did.
One of the issues I was having was cold start and cold running. I was running it fairly rich at idle because my OLSD table had some high *** numbers in there. Like the EQ was 1.15 to 1.24 as it heated up in the 65-70 kPa range. As it warmed up and leaned out to where the VE table was right, it'd definitely idle right, but when the car isn't warm and I'd back out of the garage, I was essentially dumping fuel like crazy. I'm hoping fixing that helps as well as the issue is less pronounced at temp.
Yeah. I did that months ago. Here is the current tune. I need to log it tomorrow to watch as I do low speed stuff.
You'll see I've massaged quite a bit more in there than what the HPT tuning guideline calls for... the car is a finicky bitch with the 102, 9.5" stall, and big cam.
I had made a comment early about opening the tune file issue, I normally use explorer as my browser. Downloaded Chrome for ***** & giggles, the file opens just fine.....just saying for anyone else having a problem.
The idle timing is probably way over best idle torque, so the nannies under/over speed are not able to help. The idle table needs to be few degree's under best torque so when the under speed steps in it can actually help. That cam is going to lope let say 50 rpm as an example, so having under/over speed correction in those cells isn't helping & possibly aggravating the condition.
A really good tip I read, in the VCM controls turn off the over/under speed timing tables. Work the fuel & air tables of course the idle timing for the best stable idle you can get. That would include those idle load conditions such as turning the wheel, then turn the over /under speed timing tables back on.
The BRAF does not seem right BTW, how are doing that?
The BRAF is what it calls for. It calls for a tremendous amount of air for some reason. The dumped fuel might be the cause there. It'll probably need less air after leaning out my OLSD table when I re-run the RAF.
I turned off the idle spark and tuned the a/f so it would run stable. But that was with no load. I took so much fuel out it wouldn't rev. Seriously. But it idled stable at 900 with no issues. It would drive fine because the PE mode would enable and I'd actually get moving under load. The issue was I should be able to free rev in park. So I ended up adding a bit of fuel back in in the 800 and 1200 cells in the VE table to correct that. Because it still idles fine with the overspeed/underspeed corrections, but no longer without their nanny help. I may just need to work on that balance a bit more.
As you said, it's not a bad idea to log the conditions where it stalls and see what it does and then try to figure out what it needs (more or less spark, more or less fuel, changes to the RAF/cracker/follower).
I turned off the idle spark and tuned the a/f so it would run stable. But that was with no load. I took so much fuel out it wouldn't rev. Seriously. But it idled stable at 900 with no issues. It would drive fine because the PE mode would enable and I'd actually get moving under load..
You did this with Hi idle timing? I don't doubt it would idle stable until you apply load, power is fuel So if you are taking the fuel away to that degree something is wrong...correct. Such as needing PE to get rolling.
I actually think it needs more air, which is what may happen when you find happy idle timing.
Yeah, I've seen that the RAF table changes based on the idle timing. 28-30 degrees is when it idled smooth and the kPa was in the 60s. Anything lower and it ends up in the mid 70s.
I go with what makes the motor happy, idle, off idle are more up to you than the gauges. There are expected results when you make changes, if you fall out of that then you decide the if it is acceptable or not.
Pull 10* of idle timing, hit your RTT if in VE & do a 3x3 square & find where it idles nicely. Then do a little load testing with the steering wheel & see if it is better. Just for fun of course & don't touch the pedal
02-03-2015, 08:31 PM
Low Speed Steering Stalls Motor 
So if you are taking the fuel away to that degree something is wrong...correct. Such as needing PE to get rolling.