Warning Of Dangerous Limp Mode
Mar 17, 2008 | 07:21 AM
#31
If the 4B is anything like other DBW setups, it will actually open the throttle plate ALL the way at partial pedal angles and use the stock BCS to modulate boost (and therefore tq). Problem with a BC thats not part of that system is that it allows more boost at partial pedal angles than the computer wants to see. It freaks and goes into limp mode. Will happen every time.
Mar 17, 2008 | 07:34 AM
#32
It is directly related to pressure differential. The ecu uses a fuel modifier for part throttle tip in that causes a ridiculously rich misfire. It is a preventative measure to keep the car running safely. It can easily be fixed with the new EkuTek software comming out.
It will not cause any damage. It just removes a tremendous amount of timing lead.
We have since fixed the problem by running a standalone.
It will not cause any damage. It just removes a tremendous amount of timing lead.
We have since fixed the problem by running a standalone.
Mar 17, 2008 | 07:43 AM
#33
I'm getting this code also and haven't been able to get the description for it.
I installed a AEM Tru boost controller. I get a CEL light boosting partial throttle in
5th gear and the car doesn't go into limp but at a stop my rpms are sitting at 2k???
I installed a AEM Tru boost controller. I get a CEL light boosting partial throttle in
5th gear and the car doesn't go into limp but at a stop my rpms are sitting at 2k???
Mar 17, 2008 | 09:24 AM
#34
A lot of people seem to think the ecu is blind when you turn up the boost. This is not likely to be the case. The X has a map sensor as well as a maf sensor, I would imagine the map is used to regulate boost and trigger overboost codes, easily fixed with the PROcede or a reflash, the maf output will go up with boost and as a result your calculated load will go up providing more than adequate fueling for the given boost pressure.
In short just because the throttle is at 60 % and the boost is at 22psi does not mean your calculated load would be lower than it would if the throttle were at 100%.
I don't know much about the drive by wire hardware, but is it possible that if you hit a load or boost based fuel cut while at part throttle that the throttle plate could change position fast enough or erratically enough to trigger the throttle cell code?
In short just because the throttle is at 60 % and the boost is at 22psi does not mean your calculated load would be lower than it would if the throttle were at 100%.
I don't know much about the drive by wire hardware, but is it possible that if you hit a load or boost based fuel cut while at part throttle that the throttle plate could change position fast enough or erratically enough to trigger the throttle cell code?
Mar 17, 2008 | 09:58 AM
#35
Mar 17, 2008 | 10:12 AM
#37
Mar 17, 2008 | 10:25 AM
#38
bchappy, who said the AFR's were 14:1? Wasn't me. Of course I don't want 19 psi and 14:1 afr's, don't make things up to add to the conversation........the AFR's are deep in the 10's at that boost level and part throttle.
I agree Al, it would make sense it is a torque problem which is some calculation and since the boost is high at part throttle I am in agreement. I wish Ecutek would hurry the F up.
PDXEVO, I don't remember the code but that may have been it, did you get one too?
I agree Al, it would make sense it is a torque problem which is some calculation and since the boost is high at part throttle I am in agreement. I wish Ecutek would hurry the F up.
PDXEVO, I don't remember the code but that may have been it, did you get one too?
DTC P1235: Mass Airflow Sensor Plausibility
TECHNICAL DESCRIPTION
Compare the actual measurement of volumetric effi-
ciency by a mass airflow sensor signal with volumet-
ric efficiency estimated from a throttle position
sensor (main or sub) signal.
Judgment Criterion
• For 0.76 second, the difference between the volu-
metric efficiency estimated by the throttle position
sensor (main) and the volumetric efficiency esti-
mated by the throttle position sensor (sub) is 8.8
percent or less.
FAIL-SAFE AND BACKUP FUNCTION
• Fuel control is carried out using throttle opening
degree and engine speed in accordance with pre-
set map.
However, like I said, I dont get stuck in the mode after shutting the car off, and restarting it. But, I think the issue you are having is this one:
DTC P1238: Mass Airflow Sensor Plausibility (Torque Monitor)
TECHNICAL DESCRIPTION
Compare the actual measurement of volumetric effi-
ciency by a mass airflow sensor signal with volumet-
ric efficiency estimated from a throttle position
sensor (main or sub) signal.
Check Conditions
• The difference between the actual volumetric effi-
ciency and the volumetric efficiency estimated by
the throttle position sensor (main) is 0 percent or
more.
• Engine speed is 750 r/min or higher.
Judgment Criterion
• For 0.9 second, the difference between the actual
volumetric efficiency and the volumetric efficiency
estimated by the throttle position sensor (main) is
45 percent or more.
FAIL-SAFE AND BACKUP FUNCTION
• Throttle opening degree position is in default
position.
Since the fail safe is a locked throttle body, you would be limited to speed. Please send me the code the next time you get it.
Mar 17, 2008 | 10:32 AM
#39
Actual torque - permitted torque > 130N-m (96ft-lb)
If this is true for a continuous 1 second, then you go into throttle body lock mode. The requirement for the check is VE is >= 16%, and engine speed is 500/rmin or higher.
Mar 17, 2008 | 12:51 PM
#40
EvoM Community Team Leader
iTrader: (2)
Joined: Sep 2001
Posts: 3,135
Likes: 6
From: chicago, michigan, arkansas
quickly hide this thread before the X haters find them! I think I have experienced the same thing with my "stock" evo but after I just let it idle for a few seconds, it gets the boost and rpm back without actually turning off the engine.
Mar 18, 2008 | 12:07 PM
#41
No this topic is not about someone's *****
Seriously. The EVO X has a problem that I think Mitsubishi screwed up on. The car will go into a limp mode. I've had it happen to me twice now and know other shops have had the same thing happen.
Last week I was coming home from work. I went to about 50% throttle in 4th gear, which would produce peak boost with our manual controller and the car "backfired" it felt like typical fuel cut. Problem was after this happened the car had very little power. I drove the few miles that were left to my house, pulled the code and reset it with the scanner. All was good. The code was for the TPS. This made no sense. I have not touched the throttle body or any other wiring on the car.
Last week Robert and I were driving the car, again back to my house. I left town rolled into the throttle in 5th gear, again maybe 60% throttle and the car did the same "backfire". It actually felt like the i/c pipe blew off. This time was horrible, had I been in heavy traffic we'd have been killed. I could barely get the car off the road as the top speed as 20 mph. Nothing over a few percent of throttle opening would make the car move. I pulled the code on the side of the road, again a TPS code. It would not re-set. I cussed the car, cussed Mitsubishi and wished for the 4G63 and old stuff to come back! haha Then finally the code re-set. All was good again.
So, this is all I can figure and I am basing it on tuning the drive by wire ECU's in the Subaru's. My guess is because of the manual boost controller and no engine management on the car the car is seeing too much load for a given throttle percentage, when it sees this it is shutting the car down and limiting the throttle opening.
For those of you that are putting a manual boost controller on your car I just want to make you aware of this situation as it is a huge safety issue. It has only happened at part throttle, "high" boost situations. If I run the car directly to WOT it will NOT happen, ever. I have tried to force it into that situation and it won't happen.
We need some freaking tuning software!! I know it's coming, I can't wait.
Please be careful in the meantime.
Have a great day and enjoy your cars.
Seriously. The EVO X has a problem that I think Mitsubishi screwed up on. The car will go into a limp mode. I've had it happen to me twice now and know other shops have had the same thing happen.
Last week I was coming home from work. I went to about 50% throttle in 4th gear, which would produce peak boost with our manual controller and the car "backfired" it felt like typical fuel cut. Problem was after this happened the car had very little power. I drove the few miles that were left to my house, pulled the code and reset it with the scanner. All was good. The code was for the TPS. This made no sense. I have not touched the throttle body or any other wiring on the car.
Last week Robert and I were driving the car, again back to my house. I left town rolled into the throttle in 5th gear, again maybe 60% throttle and the car did the same "backfire". It actually felt like the i/c pipe blew off. This time was horrible, had I been in heavy traffic we'd have been killed. I could barely get the car off the road as the top speed as 20 mph. Nothing over a few percent of throttle opening would make the car move. I pulled the code on the side of the road, again a TPS code. It would not re-set. I cussed the car, cussed Mitsubishi and wished for the 4G63 and old stuff to come back! haha Then finally the code re-set. All was good again.
So, this is all I can figure and I am basing it on tuning the drive by wire ECU's in the Subaru's. My guess is because of the manual boost controller and no engine management on the car the car is seeing too much load for a given throttle percentage, when it sees this it is shutting the car down and limiting the throttle opening.
For those of you that are putting a manual boost controller on your car I just want to make you aware of this situation as it is a huge safety issue. It has only happened at part throttle, "high" boost situations. If I run the car directly to WOT it will NOT happen, ever. I have tried to force it into that situation and it won't happen.
We need some freaking tuning software!! I know it's coming, I can't wait.
Please be careful in the meantime.
Have a great day and enjoy your cars.
What we need is a REAL EVO....not this butchere first model year of the generation.
I would NEVER trust the FIRST year of a BRAND NEW engine and all!.....its ASKING for trouble.
Lookat the recall specs on the gov'nt sites for the first years of new cars/generations. Not only are they quirky, but they have the highest claims for 'lemon law'
Obviously , in MY personal opinion the evoX is at best a decent car....for the price! Its a somewhat nice car....but that effin sticker price is what astonishes me !...id get a MS3, a jetski and a truck and have three power sports at my disposal, not one overpriced 20-25k looking car...that goes fora whopping 40k..
Wait until the evo 11 or 12, and then i feel it will START to unleash the power.
Last edited by RED DEMON; Mar 18, 2008 at 12:15 PM.
Mar 18, 2008 | 12:09 PM
#42
TOO LATE NIKKA!
Come on...its WAY too tempting! A evoX post like this....posted by david bushur...how can you NOT want to make some snappy comment, all i need next is warrtalon creating a thread saying how he can mop the floor with his stock evo X compared to the shop cars (ams, bushur, etc)
Mar 18, 2008 | 12:11 PM
#43
in response to a PM i got within minutes of posting....
to answer- i didnt throw a single code on my car until 61k miles! not a single effing CEL! I had the perrin 02 sim, and i didnt get a p0300 until 61k!
Now i need to wait for the parasites to come and eat me away...for showing my opinion of the first model years of a generation...and linking that to the evoX
to answer- i didnt throw a single code on my car until 61k miles! not a single effing CEL! I had the perrin 02 sim, and i didnt get a p0300 until 61k!
Now i need to wait for the parasites to come and eat me away...for showing my opinion of the first model years of a generation...and linking that to the evoX
Mar 18, 2008 | 12:29 PM
#44
red demon, luckily not everyone has a bad attitude like you do, if we all did then the first year would be the last year as no manufacturer would ever build a car two years in a row that nobody bought the first year. So you can sit back and thank all us dumb asses for going out and buying Mitsubishi's first year cars so you could end up with an EVO8.
Mar 18, 2008 | 12:46 PM
#45
EvoM Community Team Leader
iTrader: (2)
Joined: Sep 2001
Posts: 3,135
Likes: 6
From: chicago, michigan, arkansas
well, I think this limp mode is a safety feature by the ECU in preventing the all-aluminum 4B11 from blowing up. It is a lot better to get all this limp mode to aggressive "mods" than having blown 4B11 all over the place. We know new owners would like to modify their evo one way or another.