Sudden Limp Mode

[ericemir]

Hi,

I was on a 3 bar calibrated stock tune last night and messing on the high way I noticed that if I held throttle at high rpm in gear my car would go into limp mode. So I would be in 3rd gear going 60 and right before I punch it I loose all power. I then started to notice that If I did light acceleration and the boost gauge would read 7~9 psi then the motor would just go into limp mode with no power at all. I let the engine idle for a moment by holding the clutch in and a few seconds later BOOM full power back...

This is so strange! Any ideas? No check engine light has come on at all. No pending codes either....

2007 Sky Redline LNF

[Iam Broke]

You missed a table or two I think, someone will post up, I'm not where I can access it right now but you need to spread out the overboost & underboost tables also.

Make sure you did BOTH MAP sensors out to the least significant digit also. I forget, 6 places past the decimal, maybe 8. Right click on the value and run Precision all the way out.

[Iam Broke]

Here you go... see if yours is close.

[ericemir]

Here are two instances where Limp happens... I have checked all my lines and everything is intact. Going to install GMPP tune to see if it still happens. This tune is Stock tune with 3 bar calibration and few other small things torque management and boost related...

[ericemir]

maybe the mass airflow vs output frequency?

[Iam Broke]

There is a limit somewhere around 13000-14000 hz that the ECU will limp out on MAF Hz but at part throttle you shouldn't be there.

[ericemir]

There is a limit somewhere around 13000-14000 hz that the ECU will limp out on MAF Hz but at part throttle you shouldn't be there.

How can I fix this?

[Iam Broke]

Larger diameter intake tube at the MAF location to lower air velocity across the MAF sensor & then tune the MAF table.

I can't open your logs here @ work so I don't know what kind of freq you are seeing.

[cobaltssoverbooster]

are you adjusting your maf using ltft+stft pid and using the values as an average to correct the editor table? that corrected maf is so far off

[ericemir]

fixed by placing stock maf setting in my tune. But do I need any calibrations at this point? if so what do I need to do?

Thanks

[cobaltssoverbooster]

in my sig there is a link.....it has all the threads you could possibly want to make your car run like it should. lnf maf calibration w/ pics is probably what your thinking of...easy to follow instructions of byt's information.

[ericemir]

Larger diameter intake tube at the MAF location to lower air velocity across the MAF sensor & then tune the MAF table.

I can't open your logs here @ work so I don't know what kind of freq you are seeing.

Im using the stock air box with the stock maf location.

The problem used to occur low on the rpm range mid-high 2000 rpm not its happening at 4000+ rpm at part throttle...

This is really frustrating cause I cant downshift and floor it it just goes into limp mode...

I am going to try the guide on how to adjust the maf but I have a feeling this might not help im not sure.

[Iam Broke]

If you're stock turbo et al and your fuel trims are in line then I doubt the MAF freq is your issue.

If you are breaking the tires loose in third, the ESC nanny is prob taking over.

I never drove a Solstice or Sky so I'm not that close to them.

It would help to see a complete list of mods, fueling, ect to get the whole picture. Hard to diagnose over the interwebz.

[ericemir]

If you're stock turbo et al and your fuel trims are in line then I doubt the MAF freq is your issue.

If you are breaking the tires loose in third, the ESC nanny is prob taking over.

I never drove a Solstice or Sky so I'm not that close to them.

It would help to see a complete list of mods, fueling, ect to get the whole picture. Hard to diagnose over the interwebz.

Stock Turbo, Stock everything except a Tial BOV. The car ran great till I did my 3 bar calibration....

Just goes into limp mode prevents throttle past 40% and just a hazard on the highway cause it wont accelerate

[Iam Broke]

Disconnect the BOV and hook up the stock BPV and try it. All the BOV is is a noisemaker screwing up your fuel trims every time it pops. The MAF meters the air thinking the engine is getting it, then poof, it's gone and you go way rich every time it blows.

What # spring is in the BOV? Is it popping off under the higher boost? Not seating? Leaking?

[ericemir]

I dont think its the BOV. I am sitting at a stand still not moving and when I rev the motor past 3500 rpm it will go into limp mode. I am also getting a EVAP error code... P0441 and a wastegate solenoid gate A code.... Happened twice since this limp mode started....

[ericemir]

Guys this is my log this morning and I got another wastegate solenoid code... but it holds boost just fine and I have full control over boost. I have lowered and raised the boost and the wastegate is working just fine. BOV isnt opening or leaking at all. Going to inspect all my pipes and couplings but its odd its going into limp at the same exact rpm at the same load consistently.... Any suggestions will be greatly appreciated.

Thanks all

[planethax]

What are the exact DTCs you are getting?

[cobaltssoverbooster]

ok so you hae an evap code you listed, but as stated we need to know the others as well. so every code it throws in your log jot the number down for us. 8)
this is what i see:
in the scanner log:
-your maf sensor is of by at least on average +6.5% fuel.
-your throttle pedal is 100% but your tb is around 40% when your at the 2300rpm range? limp control is quite a possibility, the nanny shuts the plate a significant amount when in limp or traction control situations. other than the the high swings of the fuel trims i see everything else is pretty much in line with the regular running.
in the tune:
-you still havent fixed the 3bar maps i think i mentioned to you at some time...or maybe not but, its under engine diagnostics. (i circled the error in red) copy and paste the value from the lower section:
boost sensor p0236 to the problem spot. run the precision all the way out to the maximum decimal place before copy and paste.
-and for the overboost error you can use the stage kit values in all the boxes except for the one i have open in the picture and if you max it out it should prevent the map overboost codes from triggering, someone please correct me if they have better luck changing all of them because i personally havent had a problem with leaving the other over/underboost values alone.

by fixing the map scaler that i am seeing then you should be good to go, and im pretty sure it will make your maf trims a little bit easier to tune as well.

[ericemir]

This morning car went into limp at idle... no boost at all, no throttle response... felt like I was riding my lawn mower... The check engine light was on for the wastegate solenoid. I pulled over and swapped out my wastegate solenoid for my CBP solenoid and the damn car came back to life and ran like a bat out of hell!!!! ZERO limp mode ZERO check engine light car is perfect. going to stop by the dealer to pick up a wastegate solenoid because the mounting of these are different....

Before P0441 came on once or twice but not as often this morning its the only code that came on and would turn back on as soon as i would erase it. Problem solved!!! WOOT!!!!

Thanks all for your patience and help.