First Log with DSMLink, Help me get rid of 5,000 / 5,000 RPM Stutter

[majik2k5]

Ok, here it goes. This is the first log I've taken with DSM Link, so every setting on the car is how it was set when I got it.

I'm running roughly 20 pounds of boost, and would like to get it dialed in right around in that area.

However, around 5,000 to 5,500RPM's, or somewhere right in between there, the car starts to hesitate and buck, like it doesn't want to go past there at all.

I logged and, and was hoping someone could tell me what was going on and give me a little help into curing this problem.

http://webf1.filecrunch.com/hitfile...055c956dabb16ae7666b636b8b7/run12272007-1.dat

 

[gixrman]

I can't open the file, have you done a boost leak test? Can you just load the dat. file?

 

[greentrbo_95gst]

"The page is currently unavailable"

Test is for boost leaks #2 and check your plugs.

 

[majik2k5]

Car has been boost leak tested at 25+ pounds with a smoker. No leaks, and brand new plugs. Here's another link to the log.

run12272007-1.dat

 

[majik2k5]

The issue seems to be boost related after driving it around a litlte bit last night. I turned it down, and it was still there but not as violent. The thing is, I know I'm not hitting fuel cut at 20psi with a 255 and 850cc injectors, along with an AFPR. There has to be something that can be dialed in through DSMLink here to get her going strong.

 

[turbosax2]

The issue seems to be boost related after driving it around a litlte bit last night. I turned it down, and it was still there but not as violent. The thing is, I know I'm not hitting fuel cut at 20psi with a 255 and 850cc injectors, along with an AFPR. There has to be something that can be dialed in through DSMLink here to get her going strong.

DSMlink automatically eliminates fuel cut so it should never happen.

 

[majik2k5]

That was the impression I was under, but being new to DSM Link I wasn't 100% positive. And being that it's not fuel cut, I'm a little puzzled as to what else could be adjusted to cure it.

 

[turbosax2]

Is your "Invert CAS" button checked? It's found in ECU/Logfile > Miscellaneous.

I don't know if this would cause your problem or not but I thought I would mention it. The button should be checked since you are using a 1g CAS.

 

[turboglenn]

I can't see throttle position, but it looks like you're leaning out under boost if you look at the log at 39.84 seconds you will see it get knock and go lean several times in that one small area of the log.

 

[majik2k5]

So should I add fuel in those certain RPM's, or reduce airflow? Again, I'm new to DSM Link. And I actually don't have my CAS inverted, so I'm going to do that tonight when I get home.

 

[Black95TSIawd]

Do you have the clutch cut wire installed? Is it checked off that the clutch cut is enabled?

 

[majik2k5]

I don't believe the clutch cut wire is enabled to be completely honest. Could you elaborate?

 

[Black95TSIawd]

Did you wire in the clutch switch to the ECU? If you did, make sure the clutch cut feature is enabled in the RPM window.

 

[majik2k5]

I'm gonna try to contact the guy that had the car before me. He installed DSM Link on it, but I don't know about the clutch cut wire.

 

[MrBoxx]

In the "ECU" menu, scroll down to "RPMS" and make sure the "Enable clutch cut" box is unchecked. Then look at your "Rev Limit" in the same box. If you don't intend on using the clutch-cut features, put that at redline (7500rpms or so). What is the current rpm value there, as well as the "launch" values?

 

[turboglenn]

Is clutch cut, just a secondary rev limiter on the DSMlink? I've not really messed with too much on it but fuel and spark adjustments. And i had to setup something to run a GM MAP on one once. It's the regular Link Systems ECU i'm more familiar with. Also i don't get why you need to invert the CAS if it's running. Doesn't all that do is swap the firing order on the coils making you change the plug wires to get the spark right again afterwards? Or is it so you don't have to swap the plug wires? Some of the weird ass stuff they have to put into these proprietary systems confuses and annoys me.

I ask about those 2 things because I don't see what that would have to do with his engine breaking up at 5k RPM.

 

[MrBoxx]

The clutch-cut wire allows for studder-box and No-Lift To Shift functions. If the rev-limit is set at 5000 on the clutch-cut menu, the car will break up at 5000 as if it's hit a rev-limiter.

 

[gsx951]

Ok, here it goes. This is the first log I've taken with DSM Link, so every setting on the car is how it was set when I got it.

I'm running roughly 20 pounds of boost, and would like to get it dialed in right around in that area.

However, around 5,000 to 5,500RPM's, or somewhere right in between there, the car starts to hesitate and buck, like it doesn't want to go past there at all.

I logged and, and was hoping someone could tell me what was going on and give me a little help into curing this problem.

http://webf1.filecrunch.com/hitfile...055c956dabb16ae7666b636b8b7/run12272007-1.dat

Register on the dsmlink forum and post a log

 

[MrBoxx]

Just a few things I notice: Around the 5000 rpm range, you're getting almost 2 degrees of knock retard, but your injector duty cycle is only in the 60's or so. Was this a WOT run, or a gradual acceleration? I can't seem to display TPS on this log, so make sure that's one of your captured values.

Also, your coolant temps look to be around 220, which is a little high. The ECU will start to retard timing after a certain point, so that's something to look into at some point.

 

[turboglenn]

The clutch-cut wire allows for studder-box and No-Lift To Shift functions. If the rev-limit is set at 5000 on the clutch-cut menu, the car will break up at 5000 as if it's hit a rev-limiter.

I see, so there could be a possibility thyat it's checked and that the wire is either getting grounded some where ( or pulled open) depending on how it works and rev limiting the car. The part of that log I was pointing out looked like that very well could be the case.

 

[Black95TSIawd]

I used to drive with my foot leaned onto the clutch pedal. Although it isn't enough to disengage the clutch, the slightest movement triggers the clutch switch. Instead of setting the clutch cut to a higher rpm in order to not mistakenly hit it, I realized how fun NLTS is and changed my driving habits.

 

[majik2k5]

Directed towards MrBoxx,

The run was a WOT run. I've also disabled the clutch cut, and raised the rev limiters on both. The car doesn't seem to break up as bad, but it's still doing it.

 

[MrBoxx]

I admit, I don't have as much experience actually tuning with Link as I'd like. That's the plan for this year, however. One thing to try first is to get rid of that knock, either by adding fuel or pulling timing. You've got plenty of fuel left, as far as your IDC's are concerned, so you may start there. Or leave fuel as it is and pull timing down a few degrees and see if that improves anything. It certainly easy enough to make back to back pulls with the different settings and see which works out better.

 

[gsx951]

No offense to MrBoxx, or any othe contributors who have tried to help .....


Thomas and Dave at DSMlink have one of the best DSM specific forums on the net as a part of their product support.
It is free to anyone with a registered copy of DSMlink.
You need only to register and post a log.


DSMLink Homepage

 

[gixrman]

I don't know if you heard about this guide but I followed this guide and this is what I used to setup my car and start tunning with link. It worked verywell wor me. Also are you running a MAFT? I almost the same problem and it was the fuel cut dip switch. http://www.jeffgst.com/index.html