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Discussion Starter #1
Hello there, quickly checked to see if i could find this issue on other posts... couldn't find any, but didn't look for to long.

Anyways, this issue just started not long ago, (maybe a week ago i noticed it).
When im cruising at approx 50mph + with steady throttle input to stay at selected speed car will do a very light "hesitation" and my afr's will jump from 14s into the 15s for a split second. When it does this the boost goes from right at about zero or very low vaccum to a higher vaccum for a split second and then it evens out for a bit and will do it again. It's worse if cruise control is on at approx 75 on the freeway. It's not by any means an aggressive hesitation, but I can feel it as the driver, a passenger might never notice. If im in the throttle it will still build boost as it seems like it should.

Hopefully that makes some sense as to what is happening?

I am not sure on all the correct names of each line going to and from the maggie, as a previous owner did install. But i replaced the vaccum line going to the bypass valve along with all the other small lines going to and from the blower as they were starting to get some small cracks etc from age/heat. This did not fix the issue. From the bit of reading i've done maybe it could be an issue with the bypass valve? Air intake system one of the K&N tubes is slightly caved in due to a previous owner over tightening a clamp, but it still seals fine, so don't think its that causing an air fluctuation.

Any input or thoughts would be appreciated.
Car is an M6 if that helps at all.
Thanks!
 

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First: 04 or 05-06? Looks like an 05-06 from your profile pic.

Second: Post clear pictures showing all of the vacuum/pcv lines.

An intake leak after the MAF can/will cause a lean condition, so that’s definitely something to address.
 

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Discussion Starter #3
I will get pictures later and post them up!
Car is an 06.
 

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Discussion Starter #4
I circled each ends of lines I replaced due to heat stress cracks etc. Checked other lines and no cracks or visible wear. I also replaced the short small line seen in second picture that goes to the bypass valve as it was worn as well. After I replaced those I disasemled air intake to see if there were any visible issues, found the collapsed piece seen in pic 3. Even tho it seemed to still be sealed would this be first place to start? Any idea if you can buy just that piece from k&n anywhere?
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IMG_20200802_110813.jpg
 

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I’d start with that intake elbow as that’s definitely a source for an after MAF leak that can cause a lean condition.

The elbow is part of the Maggie kit, so if you can’t fix it yourself, you’d need to contact them for a new one.
 

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Discussion Starter #6
Alright so I was able to get the intake piece bent back to an acceptable spot, not ideal and eventually i'll get around to replacing, but I know thats not where my leak/issue is for now.
Took it for a cruise and it still does the same symptoms as i described. Would a failing supercharger bypass valve cause the erratic dropping out of boost (only when hovering at the "zero" psi range) and into vaccum? Along with the somewhat erratic AFR's during cruising? If I had the info/knowledge on how to do the data logging and such I would do more research before posting this stuff...

Thanks
 

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Really need HP Tuners to data log and see what's going on. Your MAF could be dirty/failing at that point which would cause a fueling error, you could have a vacuum leak somewhere, your tune could need some work, etc.

When you say your AFR's jump up to the 15's at steady light throttle, how far up into the 15's does it go? A 15.5 is roughly only 5% higher than stoich, and isn't out of the "normal" parameter in certain conditions. That said, it's always best to target your trims to be within -5 to 0% at part throttle, so am wondering if your tune may just need some adjustment. The key is what does your AFR look like at moderate to wide open throttle? I hope WOT is close to 11.5% give or take a half a percent.
 

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Discussion Starter #8
Yeah I was going to clean the maf today when I get home from work and see if that by chance fixes it. And it will go to 15.7 or so but only for a split second, gauge barely has time to display it before it drops back down to 14s...
And yes WOT is generally 11.0 -11.4ish.

How much can you get hp tuners software/tool for? Is it worth it? Or is it not worth getting and just bring it to a knowledgeable LS tuner and have them check it out? I hate to spend the money to have people work on my stuff but I also know my limitations with trying to mess with tuning which I probably have no business doing at this point as I don't want to mess up a tune bad enough to damage engine 🙄💸.
Will post later if cleaning maf helped at all.
 

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I'd really like to see a log before I comment any further. Is your wideband calibrated? They don't last forever.

HP Tuners was one of the best investments I've ever made and has paid for itself many times over for instances just like this. You'd have to search around as I have no idea what HP Tuners goes for now.

Where are you located by the way?
 

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Discussion Starter #10
Yeah I am going to look into getting it if its not to much money as I would enjoy being able to diagnose most of my issues I ever run into. But I know you pay to play as well.
And I am located in Minnesota.

Appreciate replies despite my lack of knowledge on the tuning end of things. I know guys use wideband sensors during tuning, but if sensor goes bad will it cause the tune to change and cause issues? My AFR gauge has been acting a little weird as of late and there are some reported issues about the brand "Innovative motorsports" from some reviews i've seen. Previous owner installed so I'm having to research everything as I go with this car..
 

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HP Tuners is about $395 at Summit Racing, includes the needed 2 credits. Quick blips in AFR isn't too concerning, longer than a couple seconds or so could be problematic.
 

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I'd be more than happy to look over your tune for you if you decide to buy HP tuners as you can easily email and share logs and tune files.

An uncalibrated or malfunctioning wideband used during the tuning process is bad. Once you have your tune dialed in though, a permanently installed wideband is just a monitor for your AFR's, so no, it possibly malfunctioning now would not cause any change to your tune.
 
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Discussion Starter #13
I did see it was 395 with credits at summit. Not bad if you can tune, data log, save files, diagnose etc... cheaper than most relatively basic scan tools...

I have no idea what program was used to tune my car previously as it was all previous owners... so just by the fact of plugging in a HP tuner with the unlock credits will that screw up the current tune? Or can I still data log and view things without messing up current tune?

And if i get the tuner I would very much appreciate someone looking over data logs etc!
Once again, sorry i'm new to the tuning world. But looking forward to start dabbling in it... Thanks!
 

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No. You cannot screw up your current tune by plugging any tuning software into your car unless you purposely write a new tune file to the ECM with it.

If you purchase HP Tuners, give me a holler and I'll walk you thru the steps to get it connected, pull a copy of your current tune, and show you how to setup the scanner to data log.
 

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Discussion Starter #15
I am most likely buying hptuners (without credits for now as I don't plan to tune anything just yet) so I can datalog etc...


But car finally threw a code tonight. It happened twice, it was in 6th gear both times when it happened at approx 65mph first time and 60 second time. Cruising on flat ground with light throttle input as described previously where the boost/vaccum is jumping around.
Code is P060E to do with throttle position from what I looked up. Any direction of where you would go first? Or could something else be screwing up and causing this to be persay a false code covering up something else?
Thanks
 
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