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ECMlink Why is my tune so messed up

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I had to change the ISC because I took it off to test it and found out that the plunger didnt work and the casing was cracked in 3 different spots. So, I had no choice but to change it
 
You have something really funky going on.

Your MAF signal isn't changing much at all (like 10hz across the entire log); especially for the RPMs that you are cycling. This probably explains why your ISC is just sitting there around 34 and not trying to control the idle, and timing is just cycling at what it normally would based on the RPM...rather than dropping down to even things out. Based on just the MAF signal, it almost looks like your ECU doesn't know that their is an airflow problem....and yet there is definitely surging.

As for the O2 signal, it's just bizarre. My guess is that your AFRs are so out of whack due to the surging and lack of MAFComp adjustment that it just isn't reading correctly.

I still don't know why you decided to fix stuff that wasn't broken. You just about had everything dialed in, and then switched out the MAF, ISC, etc. (Cracked or not, your ISC was working and looked pretty normal in the earlier log).

When you changed the ISC, did you mess with the idle switch or throttle cable?
 
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Sorry if this is an obvious question, but how much can a leaking valve cover gasket affect idle? If any.. I'm still unable to get my idle stable. What else could cause the problem besides vac leak and IAC "brand new 2 weeks ago" im thinking maybe the Tps?
 
I'm actually in the process of looking for a VC gasket. The engine holds air up to 35psi , so would that mean it is for sure a vac leak? And can that leak be bad enough to make my car idle at 2500 rpms?
 
You would know if the valve cover is leaking badly enough to have air escape from the gasket. You would be able to hear/feel it. If the car holds 35 psi without a problem, then I'd say you don't have a leak at the valve cover that should cause any issues with idle.

I think you should drive down to me and I'll take a look at it. There's got to be something small/stupid causing this. I don't even remember what all you've checked other than the ISC.
 
I just took this log today. I switched my Maf with my old one and i adjusted the BISS and got the idle to stablize till the end of the log. I've went through everything I can think of and just replaced with new parts. Only thing I did fix was my catch can vac leak. I never had a problem with it this way before the turbo went. Any pointers or settings that look weird or idea of why it would of just very slowly stalled. Thank, :thumb:

You would know if the valve cover is leaking badly enough to have air escape from the gasket. You would be able to hear/feel it. If the car holds 35 psi without a problem, then I'd say you don't have a leak at the valve cover that should cause any issues with idle.

I think you should drive down to me and I'll take a look at it. There's got to be something small/stupid causing this. I don't even remember what all you've checked other than the ISC.

The valve cover leaks oil out of the seam between the head and the VC. Thats what made me think maybe a new gasket was needed. It probably is something small causing all my problems, knowing my luck :ohdamn: But I dont trust driving the car at all even around the block. the tune is so out of whack and i dont really want to risk doing any kind of damage that could have been avoided. Thats why I havent really even tried to mess with it too much latly. Im not sure what safe and whats not and what I can do and what I cant do.
 

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1. Why are your MAF settings in the -40% range for idle? That should not be that low and will indicate your fuel settings are incorrect.

2. You have no front o2 signal as it's sitting at .02v. This will cause a really bad idle. Try setting up narrowband sim based off the wideband input and see if you can get a cycling front o2 signal.

3. Your ISCPosition value is maxed out at 120. There's something not working right there - either the ISC is compensating too much for a leak or something's broke.
 
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1. Why are your MAF settings in the -40% range for idle? That should not be that low and will indicate your fuel settings are incorrect.

2. You have no front o2 signal as it's sitting at .02v. This will cause a really bad idle. Try setting up narrowband sim based off the wideband input and see if you can get a cycling front o2 signal.

3. Your ISCPosition value is maxed out at 120. There's something not working right there - either the ISC is compensating too much for a leak or something's broke.

The maf setting are like that because the airflowperrev would not drop lower then .36. I was wondering also why those sliders dropped so low before it made a change.


Ill try and see if I can sim the narrowband and see what happends :thumb:


I think the BISS needs to be tightened in just alittle bit to make that value drop some "hopefully" Its been awhile since I messed with this car. I moved to buffalo and its just been sitting at my parents house in rochester Because I dont trust the way things are going with this car and I dont have the money to bring it to a shop like STM :banghead:
 
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