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Need help! Hesitation after cold start.

cgriffin

New Member
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Location
Laguna Vista
#1
Hey guys so I bought my 14 FIST about 5 months ago with 10,000 miles on it. The problem I'm having is that after a cold start. IF I don't let the car warm up 100% before driving off I will experience a sort of hesitation in the first couple of gears during acceleration. I have always just chalked this up to the warm up process. The car has done this since I bought it about 4 months ago and I now have about 18,000 miles on it now. I want to try and get this resolved before I feel comfortable doing any real performance modifications. Or atleast discover if it's normal or not.

Cody
 


zanethan

Active member
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557
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192
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Charlotte
#2
I'm going to resurrect this thread as mine seems to be doing the same thing. It only does it when the engine is cold and only after the first start. After that everything is normal.
 


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0
Location
Ballarat
#3
Sorry to resurrect the thread again, my car does the exact same thing, been doing it from new, kind of disconcerting.
 


CanadianGuy

4000 Post Club
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942
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Southern Ontario
#4
Sure its not an EVAP issue. Overfilling the gas tank will, over time, cause issues in the EVAP system which is described as almost stall/hesitation. Never try to top up. Just putting out there as information, not as anything definitive.
 


zanethan

Active member
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Charlotte
#5
Can't comment on others but I never overfill my tank. Once the pump clicks off once I stop filling the tank.
 


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5
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0
Location
Ballarat
#6
Yep, I always stop filling at first click too. Good suggestion though CanadianGuy good advice in general.
 


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182
Location
corpus christi
#7
It is normal. I probably won't say this as good as a tuner would, but your ecu is in an "open loop" mode while warming up. Once warmed up it goes into a "closed loop" setting and your car will run normal. People who slowly cruise off with a cold engine won't notice like someone who has to immediately get going. After a few seconds of driving, the car is warmed up enough to go to the "closed loop" setting. I know that's probably not the exact way to say it, but in a nutshell everything is OK with your car.
 


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Location
Ballarat
#8
This does sound like the most reasonable explanation, it's possible that the throttle map is different in open loop, which is what mine feels like. Thanks for the post!
 


Quisp

1000 Post Club
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Davenport
#9
It is normal. I probably won't say this as good as a tuner would, but your ecu is in an "open loop" mode while warming up. Once warmed up it goes into a "closed loop" setting and your car will run normal. People who slowly cruise off with a cold engine won't notice like someone who has to immediately get going. After a few seconds of driving, the car is warmed up enough to go to the "closed loop" setting. I know that's probably not the exact way to say it, but in a nutshell everything is OK with your car.
Isn't it the opposite?
http://www.clarkscarcare.com/cars-optimal-temperature-explained-closed-open-loop-cycle/
 


Messages
173
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28
Location
LA
#11
You're not alone. I've noticed this with my car as well. The first few hundred yards after a cold-start has an odd throttle response, almost as if the turbo isn't spooling. I wouldn't really call it a hesitation as the engine doesn't stumble or misfire; it just seems less responsive. Once I'm around the block, though, all is well. Its done this since new and I have 20k miles on the clock with a Mountune MP215 kit. Did it both with and without the re-flash.
 


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1
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0
Location
UK
#12
Hi guys,

I have an MP215 upgrade, 17K miles with the same problem. The turbo doesn't spool much until the 4th bar on the engine heat meter is reached. From what I've read so far, this is by design, to allow the oil to warm up to operating temperature before full power is enabled.
 


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