i think i know what limp mode feels like...[help!]
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Joined: Sep 2005
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RE: i think i know what limp mode feels like...[help!]
ORIGINAL: brrman
Not an accurate description there, kakarot....
Limp mode is engine controlled - not TCU controlled. Boost is limited to 5psi. It does not prevent your car from changing gears in D mode. It does not even prevent overdrive. It is merely a preventative measure take by the ECU to tone down the parameters of the engine when it recognizes an malfunction or anomally.
onePoint8Tee - if you are DBW then is could be your manifold absolute pressure sensor (MAP). It can throw the car into limp more if one or more parameters steps out of place (ie gets too high). Happens to me sometimes when I really hammer it off a stoplight. It's not really a problem. Clearing the code will fix this. Most times restarting the car too.
ORIGINAL: kakarot
LIMP MODE, is when tranny stops using TCU, when that hapens you have to use gear lever to switch between gears. its nasty and you cannot go into overdrive mode. what you have is simple mulfunction of the engine.
LIMP MODE, is when tranny stops using TCU, when that hapens you have to use gear lever to switch between gears. its nasty and you cannot go into overdrive mode. what you have is simple mulfunction of the engine.
Limp mode is engine controlled - not TCU controlled. Boost is limited to 5psi. It does not prevent your car from changing gears in D mode. It does not even prevent overdrive. It is merely a preventative measure take by the ECU to tone down the parameters of the engine when it recognizes an malfunction or anomally.
ORIGINAL: onePoint8Tee
Whenever i drive REAL fast i go into limp limp mode.. Like over 100mph and really aggressive driving. Its happened a few times.. I just restart and its fine. Maybe that a MAF going bad?
Whenever i drive REAL fast i go into limp limp mode.. Like over 100mph and really aggressive driving. Its happened a few times.. I just restart and its fine. Maybe that a MAF going bad?
Joined: Nov 2005
Posts: 12,826
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RE: i think i know what limp mode feels like...[help!]
code 16684 is the cause of all the other codes ( random/multiple cylinder(s) - misfire detected ), areas to check are spark plugs, plug leads, injectors, ignition coil(s), low compression, wiring.
now whats that burned wire your on about
now whats that burned wire your on about
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2nd Gear
Joined: Dec 2004
Posts: 614
From: Asheville, NC
RE: i think i know what limp mode feels like...[help!]
sweet...thanks for all the help everyone. Today I ordered a new ICM after researching on AZ and AW forever. Testing it sounded like a real PITA, so I'm going out on a limb here. The stealership wanted $373 and I got it shipped for $80. 
Anyway, we'll see what's going on. And I found out that my frayed wire is a ground wire, so I'll fix that too. If this doesn't solve the problem then I'll check the injectors and wiring a little more carefully but everything I researched pointed to the ICM (little thing on top of the airbox).
Anyway, we'll see what's going on. And I found out that my frayed wire is a ground wire, so I'll fix that too. If this doesn't solve the problem then I'll check the injectors and wiring a little more carefully but everything I researched pointed to the ICM (little thing on top of the airbox).
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Joined: May 2003
Posts: 3,927
From: Indianapolis, IN
RE: i think i know what limp mode feels like...[help!]
onepoint8tee
Its not a malfunction of the MAP, its the MAP doing its job because it noticed some parameters out of spec for a split second. This is common for chipped cars to send parameters like this on very hard acceleration. Don't give it any more thought. Its not a problem unless it happens to you during normal driving.
Its not a malfunction of the MAP, its the MAP doing its job because it noticed some parameters out of spec for a split second. This is common for chipped cars to send parameters like this on very hard acceleration. Don't give it any more thought. Its not a problem unless it happens to you during normal driving.
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Joined: Sep 2005
Posts: 13,664
RE: i think i know what limp mode feels like...[help!]
ORIGINAL: brrman
onepoint8tee
Its not a malfunction of the MAP, its the MAP doing its job because it noticed some parameters out of spec for a split second. This is common for chipped cars to send parameters like this on very hard acceleration. Don't give it any more thought. Its not a problem unless it happens to you during normal driving.
onepoint8tee
Its not a malfunction of the MAP, its the MAP doing its job because it noticed some parameters out of spec for a split second. This is common for chipped cars to send parameters like this on very hard acceleration. Don't give it any more thought. Its not a problem unless it happens to you during normal driving.
Joined: Aug 2005
Posts: 1,561
From: Brooklyn, NY
RE: i think i know what limp mode feels like...[help!]
DUDE okey:
limp mode is a mulfunction on the tranny computer
closed loop mode is when its is asociated with ECU.
EXAMPLES:
Limp mode- for example when TCU detects that governer is mulfunctioning, the TCU throw into limp mode it which driver uses gear selector to switch between gears. it stais like that till mulfunction is elimited and TCU reseted or not. That hapens becouse TCU does not know when to switch gears. FAILSAFE
Closed loop mode- most noticble when engine is cold and just started, even though it does not say that it is. another is whne a sensor mulfunctioning, the ECU jumps into closed loop mode, in which the ECU skips sensors and uses basic programing to operate the car. it does use crancshaft position sensrot and some more basic sensors.
NOTE: the limp mode and closed loop mode have levels, there are simple and more complex. the basic failsafe on limp mode is restriction of overdrive. the restriction of closed loop mode is a lot so basicly it reverses it self into basic system, like old 5000 and 4000 and more.
to see closed loop try boosting full when the engine is cold, as when just started.
limp mode is a mulfunction on the tranny computer
closed loop mode is when its is asociated with ECU.
EXAMPLES:
Limp mode- for example when TCU detects that governer is mulfunctioning, the TCU throw into limp mode it which driver uses gear selector to switch between gears. it stais like that till mulfunction is elimited and TCU reseted or not. That hapens becouse TCU does not know when to switch gears. FAILSAFE
Closed loop mode- most noticble when engine is cold and just started, even though it does not say that it is. another is whne a sensor mulfunctioning, the ECU jumps into closed loop mode, in which the ECU skips sensors and uses basic programing to operate the car. it does use crancshaft position sensrot and some more basic sensors.
NOTE: the limp mode and closed loop mode have levels, there are simple and more complex. the basic failsafe on limp mode is restriction of overdrive. the restriction of closed loop mode is a lot so basicly it reverses it self into basic system, like old 5000 and 4000 and more.
to see closed loop try boosting full when the engine is cold, as when just started.
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Joined: May 2003
Posts: 3,927
From: Indianapolis, IN
RE: i think i know what limp mode feels like...[help!]
hmm... yeah I agree you are pretty much correct after brushing up on my reading, kakarot.
What is typically called "Limp Mode" by many of us is not really limp mode at all, but simply the car reacting to odd sensor data via Closed Loop mode.
And yes, I do stand corrected - the TCU is affected by Limp Mode. Like when all the gears light up in the dash at one time. But I think you got it backwards with the gear shifting - it does not allow you to use the tiptronic. It only allows D mode. I have had my tranny in limp mode in my old car before and I noticed my tip function did not work. But like you said, maybe it it has diff levels of operation.
So in OnePoint8Tee's case - his car would effectively be going into Closed Loop Mode after his MAP sensor recorded unanticipated levels. Not limp mode.
I'm glad you did, drkenan - it's not often anymore that I find out anything new about my car...
cool beans
What is typically called "Limp Mode" by many of us is not really limp mode at all, but simply the car reacting to odd sensor data via Closed Loop mode.
And yes, I do stand corrected - the TCU is affected by Limp Mode. Like when all the gears light up in the dash at one time. But I think you got it backwards with the gear shifting - it does not allow you to use the tiptronic. It only allows D mode. I have had my tranny in limp mode in my old car before and I noticed my tip function did not work. But like you said, maybe it it has diff levels of operation.
So in OnePoint8Tee's case - his car would effectively be going into Closed Loop Mode after his MAP sensor recorded unanticipated levels. Not limp mode.
ORIGINAL: drkenan
^^ Maybe I shouldn't have included "limp mode" in the title.
^^ Maybe I shouldn't have included "limp mode" in the title.
cool beans
Joined: Aug 2005
Posts: 1,561
From: Brooklyn, NY
RE: i think i know what limp mode feels like...[help!]
^^^^^^^^ you welcome.
well some cars like mine old when it goes into limp mode it starts to jerk and you use the gear select to switch. On new cars is posible or even likly that only D works. each tranny is a bit diferent. so I agree with you too.
well some cars like mine old when it goes into limp mode it starts to jerk and you use the gear select to switch. On new cars is posible or even likly that only D works. each tranny is a bit diferent. so I agree with you too.
