First cruise log

[RocCitySlayer]

Here is my first cruise log.. it hit knock at a 5th gear pull but then it didnt come back at all. i have a couple more logs and yes they all have a few quick pulls.. "even though its untuned " I know its not the smartest but oh well i just got the car running good... any advise is appreciated

Does everything look ok untill i can get it tuned? hopefully going to bring it to stm this week

 

[snowborder714]

There's either an issue with your ISC or your BISS needs adjusted pretty badly. Looking at the 2nd log posted, your ISCPosition is maxed out at 100.

Once you get that fixed, monitor your AirflowPerRev value and CombinedFT to make sure they're in check.


Your cruise log looked pretty good.

 

[RocCitySlayer]

I cant get the ISC to stay steady at one number in link. It eather goes to high or to low. The biss screw seems to only lower the idle... Is there something im not doing right?

Thanks for the reply

 

[snowborder714]

And it tested out fine with a multimeter?

Did your boost leak test show any leaks at the BISS screw? Or the ISC o-ring? Just trying to cover common leaking areas. I think you already mentioned the shaft seals were fine.

The only reasons you wouldn't be able to get it solid and down is either a bad ISC unit or a boost leak.

 

[RocCitySlayer]

And it tested out fine with a multimeter?

Did your boost leak test show any leaks at the BISS screw? Or the ISC o-ring? Just trying to cover common leaking areas. I think you already mentioned the shaft seals were fine.

The only reasons you wouldn't be able to get it solid and down is either a bad ISC unit or a boost leak.

I tested it once on the car. Then again when i had the throttlebody off the car to change the shaft seals and everything tested fine at 38-42 ohms. With the boost leak test i finally got the throttlebody to seal completly and changed to biss oring and i did another BLT and there are no leaks.. So Im kind of confused

 

[snowborder714]

Idle the car up to temp and back the BISS out as far as you can until either you see a change or the car starts to idle like crap/die. Check the ISCPosition value. See if you can get it to change that way.

 

[Burntz]

Did you ground the diagnostic pin through ecm link before adjusting your biss to find find a proper idle? I believe thats how you do it

 

[RocCitySlayer]

Idle the car up to temp and back the BISS out as far as you can until either you see a change or the car starts to idle like crap/die. Check the ISCPosition value. See if you can get it to change that way.

Ok ill try to go do that in a few minutes. Im planning on bringing it to Stm to get the car tuned next week. In your OPINION do you think its good enough to have tuned?

Did you ground the diagnostic pin through ecm link before adjusting your biss to find find a proper idle? I believe thats how you do it

No i didnt. I heard about that but I didnt know if was something I had to do or not

 

[snowborder714]

FWIW, I've never grounded anything when adjusting my BISS. Just get it up to temp (after making sure there's no boost leaks) and slowly adjust. After a small adjustment, let it sit for a bit and relearn idle and settle out.

If you're taking it some where, I don't think there's any "good enough to have it tuned". If they're a good shop, they'll make sure idle/cruise is tuned well and all the basics/normal stuff is set and has been covered before tuning WOT. I'm one to do it myself, so I don't know how shops normally handle this or what they look for to consider a car "good enough for WOT tuning".

 

[RocCitySlayer]

FWIW, I've never grounded anything when adjusting my BISS. Just get it up to temp (after making sure there's no boost leaks) and slowly adjust. After a small adjustment, let it sit for a bit and relearn idle and settle out.

If you're taking it some where, I don't think there's any "good enough to have it tuned". If they're a good shop, they'll make sure idle/cruise is tuned well and all the basics/normal stuff is set and has been covered before tuning WOT. I'm one to do it myself, so I don't know how shops normally handle this or what they look for to consider a car "good enough for WOT tuning".

How long should I let it idle after adjusting to make sure it fully settles?

I want to do as much as I can myself. But Im going to have it fine tuned and dynoed. I took it out yesterday to do the logs and when it pulled it pulled SOOO hard. But I want to make sure its done the right way

 

[snowborder714]

Watch ISCPosition and see when it stops fluctuating a lot. It should settle in to bouncing around some number at some point (e.g. 30±3).

If you're looking to have it fine tuned, then I'd say you're not ready at all. You haven't got the idle under control, which means you haven't even started on WOT tuning. If you want them to do all of your WOT tuning, then that's fine.

I'm sure it pulls hard. And I can make it pull even harder (lean it out and add some timing up top with just a simple DA map change). But you have to get the basics down first.

 

[RocCitySlayer]

Watch ISCPosition and see when it stops fluctuating a lot. It should settle in to bouncing around some number at some point (e.g. 30±3).

If you're looking to have it fine tuned, then I'd say you're not ready at all. You haven't got the idle under control, which means you haven't even started on WOT tuning. If you want them to do all of your WOT tuning, then that's fine.

I'm sure it pulls hard. And I can make it pull even harder (lean it out and add some timing up top with just a simple DA map change). But you have to get the basics down first.

Im going to warm the car up now and try to get the isc correct.

And yea when I bring it to them im getting a full tune so hopefully they can straighten everything out

this is with biss all the way out almost.. its at idle by itself the whole time..

I dont understand this $hit man... If I turn the biss a hair touch and it goes from 100 to 0... I dont understand Why i cant get this thing to settle at the right spot

 

[snowborder714]

I see it hitting a bunch of positions between 0 and 100. You can't get it to stabilize on anything? That just seems weird.

The only things I can think that would cause it:
-bad ISC (maybe try another?)
-issue with throttle body that isn't allowing enough air into engine (possibly the ISC passage is obstructed)
-issue with ISC drivers on ECU board
-too thick of a BISS o-ring (did you replace it with an OEM unit?)
-boost leak

When you backed out the BISS, did the idle RPM increase?

Might provide some help as well.
idlesurge [ECMTuning - wiki]

 

[RocCitySlayer]

I see it hitting a bunch of positions between 0 and 100. You can't get it to stabilize on anything? That just seems weird.

The only things I can think that would cause it:
-bad ISC (maybe try another?)
-issue with throttle body that isn't allowing enough air into engine (possibly the ISC passage is obstructed)
-issue with ISC drivers on ECU board
-too thick of a BISS o-ring (did you replace it with an OEM unit?)
-boost leak

When you backed out the BISS, did the idle RPM increase?

Might provide some help as well.
idlesurge [ECMTuning - wiki]

I got it to stay at 34 but then I turned it alittle bit to try to lower it just alittle and it just dropped to 0 and now I cant get it to stay... and yes I got the oem oring and I just did another BLT to make sure and I have no leaks at all.. and yes the idle went way up when I turned it out thats why the rpms are so high in the log

 

[snowborder714]

I would've stopped at 34

Back it the whole way out and try starting again. If you got it to stay once, you should be able to do it again. And if you can try another ISC, I'd do that as well, just to rule it out.

 

[RocCitySlayer]

I would've stopped at 34

Back it the whole way out and try starting again. If you got it to stay once, you should be able to do it again. And if you can try another ISC, I'd do that as well, just to rule it out.

Yea I know I wanted to get it alittle lower but now im regreting it.. and I dont have another isc and my local part store wants $97.00

 

[snowborder714]

Well, depending on how close you are to STM, you can see if they have one you could try.

 

[RocCitySlayer]

is there a way to post a bigger log file without it excedding the allowed limit?

 

[snowborder714]

If it does exceed the limit, then clip it down.

 

[RocCitySlayer]

If it does exceed the limit, then clip it down.

How do I do that? Its a 800kb file and its saying the limit is 488kb. And this is the better log of them all

Edit: Just figured it out

Heres the new log.. Has a couple pulls

It seems to be running pretty good.. but if i turn my hids on the voltage drops to 12.5 then a second later its back at 13.7