ECMlink DSMLink Idle Surge.. Tuning Issue???

[crazyquik22023]

I'm having a problem with a really bad idle surge. I checked coils on ISC, ISC motor is working, No leaks, I can't figure it out. My ISCpositon is around 30 like it should be, I can't really get my airflow per revs to where they should be b/c the idle surge is too bad. If anybody has any ideas by looking at my log please let me know. Thanks

 

[Absit]

Without being able to view the log, you don't need a log, you need a link.
Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[gofer]

Under your RPM/TPS tab select the "simulate idle switch from TPS" block and it should fix your issue.

 

[crazyquik22023]

Under your RPM/TPS tab select the "simulate idle switch from TPS" block and it should fix your issue.

Ya I know I was going to try this tom. I just figure I should use the ISC sensor since it's there.. I hope this fixes the problem but I doubt it will since my ISC sensor isn't bad.

Without being able to view the log, you don't need a log, you need a link.
Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

Thanks I've read it numerous times...

 

[Absit]

Well that's what I get for posting without viewing the log. Today's not my best day.

 

[gofer]

The idle switch and the ISC have nothing to do with each other, the idle switch is controlled through your TPS. I looked through your mods list and didn't see 1g TB but its a common problem that when 2g DSM'rs switch to a 1g TB they use the TPS thats on there. You can pull the connector off of your TPS and verify it has a (4) pin 2g TPS, thats if you've swapped to a 1g TB of course.

 

[crazyquik22023]

The idle switch and the ISC have nothing to do with each other, the idle switch is controlled through your TPS. I looked through your mods list and didn't see 1g TB but its a common problem that when 2g DSM'rs switch to a 1g TB they use the TPS thats on there. You can pull the connector off of your TPS and verify it has a (4) pin 2g TPS, thats if you've swapped to a 1g TB of course.

Right I know the ISC and idle switch have nothing to do with each other. I was saying that the surge prob isn't being caused by a bad idle switch since all of the coils have resistance and the motor works. And since simulating idle from the TPS is just in a way replacing the ISC by using the TPS it shouldn't fix the problem, but it might well see tomorrow. Also I am using a 1g throttle body, with the 2g TPS.

 

[Calan]

Your idle switch and TPS look fine. It looks to me like your ISC is bottomed out (or not working), and the ECU is cranking on the timing in an attempt to manage the idle.

Do a proper BISS adjustment, set the base timing, and make sure that ISCPosition reads around 34 or so.

 

[crazyquik22023]

Looks to me like your ISC is bottomed out (or not working), and the ECU is cranking on the timing in an attempt to manage the idle.

Do a proper BISS adjustment, set the base timing, and make sure that ISCPosition reads around 34 or so.

Ya I need to adjust the BISS a little, base timing is set correctly, and I tried to get ISC Position as close to 30 as I could. Now if I simulate idle switch from TPS, the ISC postition shouldn't matter, correct? Also is there any benefit or disadvantage from using the TPS for the idle switch or using the TPS to simulate it? I can't really see that there would be any difference.

 

[Calan]

On a 1G TB, the idle switch can be a PITA to get adjusted properly. There is a very fine line between the ECU seeing a closed idle switch and how much air it lets past the throttle blade. Using the TPS to simulate it makes life much easier; not to mention the fact that it frees up an ECU switch input that can be used for things like switching to alternate AFR and timing maps.

But... as I mentioned, your TPS is reading 0% and the ECU is seeing a closed idle switch, which appears correct (unless the idle switch is not adjusted properly and is keeping the throttle blade open too much). The problem you're having is due to excessive air entering the intake that that the ECU can't compensate for; most likely because of a BISS adjustment, a vac leak at the TB or IM, or possibly an improperly adjusted throttle cable. Whatever it is, it appears that the ICS has reached it's travel limit, and the ECU can no longer use it to compensate.

Here's what I would do (with simulated idle switch):

1. Make sure there aren't any vac leaks. (BLT)

2. Make sure the throttle cable is properly adjusted, and isn't preventing the throttle from fully closing.

3. Adjust the idle switch per factory procedure.

4. Run the TPS tool in ECMLink to ensure that the TPS is calibrated.

5. Double-check that base timing is at 5* BTDC

6. Adjust the BISS per factory procedure

7. Log the car at idle again after warming it up. You should see ICSPosition hovering around 34 or so, and timing should be pretty steady at around 12*-15*, give or take a few degrees.

 

[gofer]

You could also update your firmware since you're running the old version of link.

First download the most recent stable version v3.21.40 and then download early access v3.21.109 from the ECMLink Downloads page. After doing this you'll want to update your firmware as well but to do so its a bit trickier than just clicking a link.

1. You'll want to submit a firmware request and to do it requires you to connect to your cars ECU. Click ECU from the drop down and click Create Firmware Request... paying close attention to where its saved on your computer.
2. Request Firmware Upgrade... and select Choose File and find your firmware file you just saved.
3. Download the new firmware to your desktop or somewhere you can easily access it and then open up ECMLink.
4. Click the ECU drop down menu and select Upgrade Firmware and then pick the file you just downloaded while your connected to the ECU in the car.

Craig is right, the idle switch sim from the TPS probably won't fix the issue, I could have swore last night the logged IdleSw value was 0- with 0% throttle. Basically, to correct idle surge you can use this write-up in the ECMLink Wiki. ECMLink Wiki: Idle Surge

 

[crazyquik22023]

So i just tried fixing the problem, i got the idle to be pretty good right where I want it around 1100. You can see that in this log start at about 140 seconds. But then I tried revving it to about 3000 rpms and then the idle would just sit at like 2500-3000 for a few seconds then drop back to around 1100. I then took off the throttle body to check to make sure there all of the bolts are tight etc. Then I tried starting the car again and the idle jumped to 2500rpms and wouldn't go lower.WTF I adjusted the TPS before the car was started this time, but when I did start the car the TPS% went to 5% and wouldn't go lower even if I used TPS adjust while the car was running. I'm stumped. BTW I am using TPS simulation now for idle switch and I haven't updated to the most recent firmware yet.
EDIT: I just noticed in my log that had a good idle my TPS volts were only at .15-.20volts??? Could this mean a bad TPS sensor?? Also can the TPS sensor be installed backwards??

 

[Calan]

So... did you follow all of the steps I mentioned up there in the order I listed them (especially #2 and #3)?

 

[crazyquik22023]

So... did you follow all of the steps I mentioned up there in the order I listed them (especially #3)?

Yes I did, by adjust idle switch I assumed you meant adjust TPS by moving it back and forth until it is at .63 volts.

 

[Calan]

Yes I did, by adjust idle switch I assumed you meant adjust TPS by moving it back and forth until it is at .63 volts.

Nope. The idle switch is a separate adjustment, and sets how "open" the throttle blade is when the throttle cable is fully relaxed. It's a VERY sensitive adjustment, and has to be done properly. If it isn't correct, everything goes out the window.

It's important to do things in the right order. If the throttle cable isn't properly adjusted (too tight or a binding return spring for example), you won't be able to accurately set the idle switch. If the idle switch isn't adjusted properly, the TPS will be off, etc. etc..

Go to step #1 and start over.

 

[crazyquik22023]

Nope. The idle switch is a separate adjustment, and sets how "open" the throttle blade is when the throttle cable is fully relaxed. It's a VERY sensitive adjustment, and has to be done properly. If it isn't correct, everything goes out the window.

It's important to do things in the right order. If the throttle cable isn't properly adjusted (too tight or a binding return spring for example), you won't be able to accurately set the idle switch. If the idle switch isn't adjusted properly, the TPS will be off, etc. etc..

Go to step #1 and start over.

Ok, so how do you adjust the idle switch? The cable is adjusted properly I'm just not sure how to adjust the idle switch??
EDIT: Nevermind found the answer, my throttle body doesn't have the idle switch on it but it is a 1g throttle body. So looks like I need to find an idle switch or a new throttle body.

 

[Calan]

Ok, so how do you adjust the idle switch? The cable is adjusted properly I'm just not sure how to adjust the idle switch??
EDIT: Nevermind found the answer, my throttle body doesn't have the idle switch on it but it is a 1g throttle body. So looks like I need to find an idle switch or a new throttle body.

For starters, you really need this:

Download 1G service manual (for your 1G parts)
Download 2G service manual

Nevermind found the answer, my throttle body doesn't have the idle switch on it but it is a 1g throttle body. So looks like I need to find an idle switch or a new throttle body.

DOH!

Yeah... that could be a contributing factor.

BTW - When you get everything hooked back up, make sure you have a good electrical ground going to the TB. From the factory, it's grounded to the IM via a small metal strap on the top front mounting bolt.

 

[crazyquik22023]

For starters, you really need this:

Download 1G service manual (for your 1G parts)
Download 2G service manual




DOH!

Yeah... that could be a contributing factor.

BTW - When you get everything hooked back up, make sure you have a good electrical ground going to the TB. From the factory, it's grounded to the IM via a small metal strap on the top front mounting bolt.

Yes I do have that grounded to the IM. I do not need to ground the idle switch when I put it on correct?

 

[Calan]

Yes I do have that grounded to the IM. I do not need to ground the idle switch when I put it on correct?

The idle switch just has a single wire that connects it to the ECU. When the throttle closes, the switch grounds that signal through the TB > IM > firewall > battery. (or maybe it opens the circuit... I forget; I'm a bit brain dead at the moment. )

Simulating the idle switch with the TPS in ECMLink makes that irrelevant, but you still need the switch adjusted properly since it also functions as the mechanical stop for the throttle blade.

 

[crazyquik22023]

The idle switch just has a single wire that connects it to the ECU. When the throttle closes, the switch grounds that signal through the TB > IM > firewall > battery. (or maybe it opens the circuit... I forget; I'm a bit brain dead at the moment. )

Simulating the idle switch with the TPS in ECMLink makes that irrelevant, but you still need the switch adjusted properly since it also functions as the mechanical stop for the throttle blade.

Right thats what I thought that I only need the idle switch for the the throttle stop. Thanks for the help I'll hopefully get the idle switch in a few days and hopefully it will work.

 

[snowborder714]

If you have a 2g TPS (4 pin) then you don't need to simulate the idle switch as one of those pins feeds the idle switch value. If you're using a 1g TPS, then you need to simulate it.

Your 1g throttle body should have an idle switch on it (threaded item on back side with male spade connection on top), but nothing hooked up. This is normal. But if you don't have anything there, then you probably have a bigger problem that you would have known about (sticking throttle plate).

 

[crazyquik22023]

If you have a 2g TPS (4 pin) then you don't need to simulate the idle switch as one of those pins feeds the idle switch value. If you're using a 1g TPS, then you need to simulate it.

Your 1g throttle body should have an idle switch on it (threaded item on back side with male spade connection on top), but nothing hooked up. This is normal. But if you don't have anything there, then you probably have a bigger problem that you would have known about (sticking throttle plate).

Yes, I've already come to the conclusion that I don't have an idle switch, as stated above I am using a 2g TPS, and I was only simulating the idle switch through TPS b/c of the surge.

 

[Calan]

If you have a 2g TPS (4 pin) then you don't need to simulate the idle switch as one of those pins feeds the idle switch value. If you're using a 1g TPS, then you need to simulate it.

Your 1g throttle body should have an idle switch on it (threaded item on back side with male spade connection on top), but nothing hooked up. This is normal. But if you don't have anything there, then you probably have a bigger problem that you would have known about (sticking throttle plate).

Yeah... it looks like the ECU is happy with the TPS and idle switch signals. I think he has something hosed up with the throttle plate/BISS, and the recently discovered missing idle switch could definitely be causing some mechanical issues.

I was wondering when you were gonna jump in here and help with this one.

 

[RedTurboEclipse]

sorry to bring this back up, but this comes close to my scenario.

i have a 1g tb on my 2g gsx with dsmlink. i dont have the latest link version.

anyways starting cold, it idles high at first like most.. but as it starts to get warm, it surges badly. like goes to 2000 and drops to 1500, and does that forever. the only way i can make it stop is to rev the car steady at like 3k for a while. then eventually it will settle at my set idle that i have on link.

ive tested isc and comes in spec, even switched it just for safe measure still does it. no leaks from my tests also. this only happened since the 1g tb swap.

 

[snowborder714]

Is the idle switch adjusted properly?
http://www.dsmtuners.com/forums/151826306-post2.html

Is the throttle cable adjusted properly?