07 stage 2, ecu limiting boost 8-7 psi after hitting rev limiter

[Varanont]

I have an 07sti , Up until recently the car was running like a champ. However about a 2 weeks ago I was driving aggressively, and I missed the shift from 2 to 3rd. The car was on the rev limiter for no more than 2 seconds. Immediately after doing so, the car was still fine. After parking the car for about an hour, I went to drive home and noticed that boost in all gears was limited to about 7-8 psi. Went home checked to hoses and everything was fine so I reset the ecu and took it out for a spin. The car acted normal again, and boost was hitting target ranges.

All was going well for about 150 miles when I started to drive hard again. I went from a 4 to 3rd downshift but accidentally shifted into 2nd. I caught it in time and had not even fully released the clutch, but I am pretty sure I caught the rev limiter. Once again, after parking the car for 3-4 huors, I got in the car to drive home and boost once again was limited to about half of what it normally hits in all gears. Got home, reset the ecu and all if fine again....

What is going on? Any thoughts? I am worried b/c 07' STI's seem to be having all sorts of problems.

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[Badmunky]

Originally Posted by Varanont

I am worried b/c 07' STI's seem to be having all sorts of problems.

So dose your driving?
Its probably just a safety mode as it didn't like what you did to it.
I would take some more time and go slower to go faster. You know what I mean?
Later.

[waktasz]

I've never head of this before, but if you go from 4 to 2 and overrev the motor, the rev limiter won't stop it from revving past redline.

[Varanont]

Originally Posted by waktasz

I've never head of this before, but if you go from 4 to 2 and overrev the motor, the rev limiter won't stop it from revving past redline.

On the 4 to 2 mishift, I knew almost instantly and I don't think I ever fully got off the clutch, so if I overreved, maybe it was for a second at the most. I will just have to take it easy and drive like a granny I suppose, but the ecu should not be going into limp mode from a single incident like this should it?

[smokey07]

im wondering how on earth you mistaked 3rd for 2nd.. it sounds like valet mode after it bounces off redline, but i couldnt tell you why, just put the car in gear, quit missing and your good...

[Badmunky]

I found out why its doing that for you.
I was right its a protection in the ECU.

(From Cobbs web site)

"Most critical is the fact that the
ECU (on DBW vehicles) forces the boost control system to shut down completely (so the vehicle runs mechanical boost pressure) if detonation events are continuing to occur."

Thats from the EBC FAQ.
Its saying that your car is shutting off the EBC and going off the waist gate spring set at 7-8Psi because you are getting mad KR do to over reving the motor and toping out the fuel injectors.

Thats really bad!
Keep doing that and your motor will be blown in no time!

I had a car brake a shift cable during my 3-4 gear change one time and I got 2nd gear at the top of 3rd. Only for 1/2 a sec and that was enough to blow my motor.

You said "I'm worried about all th problems with the 07 STIs."
And yet your beating the **** out of yours.
I'm surprised you didn't blow the motor with what you did.
Vary surprised actually.


Later

[waktasz]

The ECU stops listening for knock past a certain RPM, so that's not it. It could be running off wastegate spring pressure, but that doesn't seem like the reason.

[Badmunky]

That was one posable reason. THe other that the EUC may do the same thing if it sees an over rev.

Ether way what he did was not good for that motor.

Later.

[Varanont]

Originally Posted by smokey07

im wondering how on earth you mistaked 3rd for 2nd.. it sounds like valet mode after it bounces off redline, but i couldnt tell you why, just put the car in gear, quit missing and your good...

I did not describe what happened accurately, I was in 5th, meant to shift to 4th, and hit 2nd accidentally... but not even for a second b/c I caught my mistake. sorry for the confusion. Anyway, update, after resetting the ecu again everything seemed normal for about 5 miles, but now I don't even have to hit 5k rpm before the ecu decides to limit boost. I was driving normally and the ecu started limiting boost again after not even 10 miles. If the injectors were blown or maxed out, after resetting the ecu, it would not allow me to ever build up 18psi of boost right? After resetting the ecu, the car will build normal stage II boost but then the ecu shuts down everything, even after driving in everyday driving. I think the ecu is detecting detonation, but why?

I added 104 octane booster at 1/4 tank and filled up with fresh 93 oct b/c I thought the ecu might be doing this to a bad tank of gas, but the problem is still occuring.

[Badmunky]

Have it checked to see if it stored any codes and get back to us.
Later.

[CynicX]

Seems like the solution would be stop over revving the motor. Since we all know its not good for the motor (spun bearing) there really isnt a reason to fix a problem that is occurring during an accidental misshift.

I dunno the operation of an over rev event so this is just a WAG but its pretty certain to say the ECU is shutting off the boost control and limiting you to mechanical pressures (7-8psi). This may be a built in function of the ECU during an over rev on the 2007 sti, or maybe you stayed on the gas and cause the car to over boost or something of that effect. Like I said thats just a guess though.

Down shifting into the incorrect gear will mechanically over ride the rev limiter. ECU may just be trying to save the car from your driving....

Have you tried calling cobb?

[AZScoobie]

Your Advance multiplier fell to a lower number which caused the boost system to be disabled. This happens when the car is knocking or if its banging off the rev limiter. ITs a protection feature. I really suggest you calm down and focus on making the shifts smooth. Over rev is not good for these cars.

Clark

[deathinacan]

limp mode dude. happens when the ecu recognizes unsafe situations within the gazillion sensors in and around your car.

learn how to drive properly, make sure you arent forcing the car past the rev limiter. Just consider the 'no-boost' situation a sign that your ECU is doing its job in protecting your 26,000 dollar investment....

kor
www.myspace.com/projectalphaproductions

[Varanont]

Originally Posted by AZScoobie

Your Advance multiplier fell to a lower number which caused the boost system to be disabled. This happens when the car is knocking or if its banging off the rev limiter. ITs a protection feature. I really suggest you calm down and focus on making the shifts smooth. Over rev is not good for these cars.

Clark

But I reset the ecu. Wouldn't that in theory clear out the memory. After the reset, the car will drive and hit targeted boost, (this is all under normal driving conditions) and then after about 10 miles or so, it cuts off boost. Thanks for the feedback everybody.

[Loubaru]

hmmm, how many miles are you putting on a reset before you give up and reset it again? i would put a couple hundred miles on a reset and see if it sorts itself out.

[Varanont]

I just drove about 80 miles today and the ecu is still limiting boost.

[tuffstuff]

take it to the dealer

[Varanont]

I bet the dealer will say, it is normal, and they cannot do anything about it.

[Badmunky]

Try removing the Cobb tune and then reinstalling it.
See if that works.
Later.

[Varanont]

I thought it was not safe to run the car with a TBE, without some sort of EM.

[shamrock 05]

Originally Posted by Varanont

On the 4 to 2 mishift, I knew almost instantly and I don't think I ever fully got off the clutch, so if I overreved, maybe it was for a second at the most. The first time this happened was when I was using Cobb's Flat footed shifting, so I had the gas foot flat (floored) hit the clutch, misshift, heard the rev limiter bounce off. It seems like whenever the engine revs past redline, the ecu goes into limp mode. I will just have to take it easy and drive like a granny I suppose, but the ecu should not be going into limp mode from a single incident like this should it?

Yea because that RED line is there for a reason. Watch how you shift and stay off the rev limiter

[Badmunky]

Originally Posted by Varanont

I thought it was not safe to run the car with a TBE, without some sort of EM.

I think he is running a Cobb OTS stage 2 map.
If not your right he needs EM right now!
Later

[doggetr]

I have the same problem , but I dont beat on mine its just some mystery to me. See my thread: "07 STI boost problems". please help!!!

[poopy]

this happens on my 07 lgt. i have a 5eat and after being ecutek'ed this happened to me. it happens on a 1-2 shift if i punch it. ecutek did endless data logging on my car to resolve the problem. it's been a month so far and still no answer. it shows a lean condition during the actual shift. the car hits fuel cut and then runs at 8-11 psi of boost. you're probably not resetting the ecu properly. disconnect neg. battery terminal, step on brake, and then turn ingnition to full power (don't crank motor) wait for gauges to sweep, listen for a click and then start car. this is per ecutek.

[csugden]

Poopy, you forgot to reconnect the battery, gauges can't sweep without power etc.