First log with dsmlink. Car not running right

tbonitz301 · 05-14-2008, 09:49 AM

Ok guys im going to try and post this log, but im not sure how its going to turn out. First i zeroed out the global and deadtime because im running 450's at the present time. The car idles great and cruises well, but when i start to boost it really acts up so i aborted the run. Slow spool and lots of jerking,flucuating boost, and thats about it. I did the clutch wire mod that came with it. I was thinking that might be whats shutting it down, but i'd rather see what you guys have to say rather than me guessing.EDIT: hey guys how do i convert this file to raw values?

dsm-onster · 05-14-2008, 10:35 AM

Check for boost leaks. Sounds like a boost leak to me.

You're doing a run before you warm up your coolant temp sensor is outputing only 125*F. It should be around 190-200 before doing a run. Does it do this when your engine is warm?

It may be your TPS. Connect dsmlink to your laptop/pc activate dsmlink and go to "ecu/logfile". There go down to the last option "captured values..." Plug in ThrotPos and MAFRaw. And make another run when your engine warms up to 190+.

snowborder714 · 05-14-2008, 11:01 AM

Here's how to post values of the log (in a scroll box):
How to post logs so that people can actually read them.

You should do these things before starting to tune:
-verify that base timing is correct (~5 degrees)
-verify fuel pressure is correct (43.5psi - use DSMlink's fuel pump button with car off and leave vacuum line connected)
-verify no boost leaks

Here is a good guide that will get you started and show you where certain values should be at:
Basic DSMLink Tuning Guide

And for some reason when looking at your log it's showing you still have your deadtime set at 345. Not sure why but you might want to double check that.

1992awdlaser · 05-14-2008, 11:21 AM

Change your dead time and do another pull once the car is fully warmed up. Once you change the deadtime it will run better. By having the deadtime set to that it is making the injectors stay open for less time than they need to. This should cause you car to run lean.

Do you have a widebannd? How much boost?

tbonitz301 · 05-14-2008, 11:41 AM

I agree man.I dont have a wideband right now but i am getting another one. It does feel like im running lean. I'll adjust the deadtime and report back.I'm running 15psi for now till i get my 750's back.I had a problem uploading my last log, but i'll try to post this next one

steve · 05-14-2008, 11:52 AM

Quote:

Originally Posted by 1992awdlaser

By having the deadtime set to that it is making the injectors stay open for less time than they need to. This should cause you car to run lean.

I don't think so. DSMLink deadtime are additive over the stock setting. By adding 345uS make the injectors stay open longer than they would stock and run richer.

tbonitz301 · 05-14-2008, 12:25 PM

Ok. so i went for a little ride, and got a couple logs. The car is running better. I adjusted the deadtime to 145, and the global-10 and it got better, but i'm done tinkering with it till i know exactly what to do.Still running like poo

The second link is the first log. just kinda cruisin. The first link i ran the car a little harder.

1992awdlaser · 05-14-2008, 12:58 PM

Quote:

Originally Posted by steve

I don't think so. DSMLink deadtime are additive over the stock setting. By adding 345uS make the injectors stay open longer than they would stock and run richer.

Atcually, now that I think about it I think we are both wrong. Isn't deadtime when the injector is told to open and global is how long to stay open? Because it takes longer for a bigger injector to open than it does a smaller injector. This would mean the stock injectors are being told to open before they should. If this is happening I would think there is a bigger chance of the gas igniting before it should since it "sits" in the cylinder slightly longer which would cause it to heat up.

dsm-onster · 05-14-2008, 01:01 PM

Why are you running with any additional dead time? Zero out the deadtime box. Raise the global fuel slider to zero. Those are the settings for 450s. . .

Quote:

Originally Posted by 1992awdlaser

Atcually, now that I think about it I think we are both wrong. Isn't deadtime when the injector is told to open and global is how long to stay open? Because it takes longer for a bigger injector to open than it does a smaller injector. This would mean the stock injectors are being told to open before they should. If this is happening I would think there is a bigger chance of the gas igniting before it should since it "sits" in the cylinder slightly longer which would cause it to heat up.

Steve is rarely wrong about ecu workings

. Injector pulse width is the 'on time'. Global is what is told to the ecu so that it knows how long to make the pulsewidth. Deadtime is the time it takes from when the signal pulsewidth starts to the time the injector solenoid actually opens to flow fuel. This is a perameter told to the ecu with the memory, too. By typing any number in the deadtime box, the OP is making the pulsewidth longer than what the ecu normally would make it. Normally the ecu operates 450s. And the dead time is preset for 450s. The box is what is added to the original pulsewidth from the factory eprom. Steve, please correct me if I'm wrong.

1992awdlaser · 05-14-2008, 01:10 PM

Your car is running pretty hot. Your global and deadtime should be at 0 since you are using stock injectors. Hit f4 and click one time on boostest on the right. Then click on props in the middle and input your altitude. With how boostest is reading between 5000-5500 rpm right now compared to actuall boost it would indicate that you need to calibrate your maf or fix boost leaks. The value boostest shows should change when you change your altitude setting though.

tbonitz301 · 05-14-2008, 01:15 PM

I will change it back, but why does it run like crap zeroed out?I will try that. also this dsmlink was used, and i'm not real sure what i need to set to default. Like the maf for instance

1992awdlaser · 05-14-2008, 01:16 PM

Quote:

Originally Posted by dsm-onster

Injector pulse width is the 'on time'. Global is what is told to the ecu so that it knows how long to make the pulsewidth. Deadtime is the time it takes from when the signal pulsewidth starts to the time the injector solenoid actually opens to flow fuel.

Exactly. Global changes how long (pulse width) the injector will stay open. Deadtime will determine when the ecu needs to tell the injector to open not for how long though.

Do you see what I am saying? Maybe I am wrong though.

steve · 05-14-2008, 01:24 PM

Quote:

Originally Posted by 1992awdlaser

Actually, now that I think about it I think we are both wrong.

Isn't deadtime when the injector is told to open and global is how long to stay open?

Nope.

The global is a sizing factor. How big the injectors are. It's used to calculate the base injector pulse width to get a 14.7:1 AFR from the current airflow. That is then modified when running open loop to hit a target AFR by the fuel maps.

Deadtime is the correction by voltage needed to account for the fact than mechanical devices need time to work. Time after the electricity is turned on for the pintle to move and open the injector and time after it's turned off for the injector to close. The ECU has values stored to the stock injectors at different voltages and the parameter you enter into DSMLink is added to them.

Once all the pulse width corrections are made the dead time is added and the result stuffed into a timer.

Quote:

Originally Posted by 1992awdlaser

Because it takes longer for a bigger injector to open than it does a smaller injector. This would mean the stock injectors are being told to open before they should.

Almost right. What it means is that the stock injectors are spraying fuel longer than expected since they don't need as much time to open as currently programmed. That extra time = extra fuel = richer.

Quote:

Originally Posted by 1992awdlaser

If this is happening I would think there is a bigger chance of the gas igniting before it should since it "sits" in the cylinder slightly longer which would cause it to heat up.

Big reach here. You assume that the injectors are firing while the valve is open. That's actually a short window of time compared to the total time between cycles.

1992awdlaser · 05-14-2008, 01:38 PM

Quote:

Originally Posted by steve

Almost right. What it means is that the stock injectors are spraying fuel longer than expected since they don't need as much time to open as currently programmed. That extra time = extra fuel = richer.

I think I know what you mean now because of this statement. You mean the injectors are being told to open sooner by the deadtime setting, so they do. But since they open quicker than the injectors that the deadtime value is for they actually open even quicker which in turn means they start spraying the fuel sooner and they stay open for the normal amount of time for stock injectors. This means there is extra fuel. If I am wrong you can pm me if you want to keep this thread on topic.

This could explain why it ran better in the second set of logs since you changed the global to subtract fuel. So that will make up for some of the extra fuel the deadtime is adding. In the firstlog global wasstock and deadtime was 345. In the second set of logs both were changed to make up for eachother. Set both to zero and it should run better.

steve · 05-14-2008, 02:02 PM

Quote:

Originally Posted by 1992awdlaser

You mean the injectors are being told to open sooner by the deadtime setting, so they do.

Not sooner, longer. The start of the injector pulse is fixed to cam angle events. How long the injectors stay open is variable.

Quote:

Originally Posted by 1992awdlaser

But since they open quicker than the injectors that the deadtime value is for they actually open even quicker which in turn means they start spraying the fuel sooner and they stay open for the normal amount of time for stock injectors. This means there is extra fuel.

Yes since the stock injectors don't need the extra 345uS that the DSMLink deadtime parameter added, they spray fuel during the extra time. They aren't opening quicker than stock injectors because they are stock injectors but they will spray longer due to the additional time added to the IPW by the DSMLink deadtime parameter.

90laserRSfwd · 05-14-2008, 02:23 PM

whats the deal with your knock sensor? is it loose or something? why do you get a constant 3 degree's of knock?

tbonitz301 · 05-14-2008, 03:07 PM

I'm not real sure. I better make sure it's still torque'd to spec. This is the scenario. Car ran awesome. Installed dsmlink immediately after taking a ride. Global and deadtime are zeroed out. Car runs like crap.I had an aftermarket chip in it before. I believe it was a tmo chip. My question is what did that chip have that i havent added back into the equation.Also my injectors are neon green where they go into the fuel rail. Those are 450's right

Edit: for some reason the car runs better at -15 global, but im sure thats not right. any suggestions guys?

1992awdlaser · 05-14-2008, 03:37 PM

Quote:

Originally Posted by steve

Not sooner, longer. The start of the injector pulse is fixed to cam angle events. How long the injectors stay open is variable.

Yes since the stock injectors don't need the extra 345uS that the DSMLink deadtime parameter added, they spray fuel during the extra time. They aren't opening quicker than stock injectors because they are stock injectors but they will spray longer due to the additional time added to the IPW by the DSMLink deadtime parameter.

Thanks for explaining.