boost and hesitation

[speedmo21]

hey im boostin around 9psi in my msp..sometimes when i accelerate hard my car hestitates alittle bit..ive seen people talkin about this.. but what is this from and is there anything i can do or buy to make it go smoother? ihave those ngk plugs too..that are 1 step colder..i was thinkin maybe iridium plugs

 

[MSP#735]

try a FCD (fuel cut defender) that will most likely help out ALOT! they run about $45-$50.....

 

[CrackedOutMSP]

I've got the same problem like in 2nd and 3rd gear accelerating hard it feels like the car is struggling to go then eventually it breaks out, doesnt happen all the time though and I"m boostin 10psi

 

[MazdaspeedZOOM]

you might get slight hesitation no matter what you try, nature of the car we own... A Fuel Cut Defender may even it out a little bit, thats what it did for me and i'm running a lot more boost than that... Also you may be experiancing some of the heat soak of the intercooler...

 

[Bhamsan]

Engine management.

 

[speedmo21]

fcd..what exactly does the fcd do? also is it a b**** to install or what? dont know muhc about this

 

[irr5302]

unichip + good gas 93+

solve all your problem

 

[jonbig]

its prolly heat soak from that tiny as stock SMIC

 

[Yay-Boost]

Fcd is fairly easy to install. You attach it to a vacuum line and tap into an electrical line going into the computer. When you go into boost it triggers a switch that reduces the signal comming from the MAF so the computer thinks the car is seeing less air than it really is. The stock computer shuts down once a preset air flow is reached. The FCD sends an adjusted signal so the shutdown happens at a higher air flow amount.

 

[irr5302]

when you up the boost this increase the intercooler heat and the computer pull the time when detect detonation

unichip + FMIC is the best solution

 

[03MSP]

Fuel Pressure Reducer (FPR) would help more than FCD if you aren't hitting spark cut from boosting too much.

 

[EvilMSP]

Also you can learn to get around it. If you want a real fix everything listed above is great but you can also limit the hesitation through good driving. Once you learn when/how the car goes into massive lag mode (lol.) You can play with the throttle and find ways to ease into it a little more, or when in the rpm range to accelerate hard. It's kind of hard to describe but after having my car for a year + I can pretty much stop the lag from happening just by using the pedal wisely. A good fine touch can really change how the car drives. Cause at certain rpm's if you give just a little too much gas BAM it bogs down with too much fuel.

Now of course with good mods you wont need to bother with this. But it's a free and easy thing you can do yourself.

 

[Dr.Sound]

^ exactly what i learned to do

 

[thunder]

I always thought that at a certain RPM (don't remember but around 4500) our PMC goes open-loop, which means it dumps max fuel regardeless of boost etc... You may have a spike that triggers the fuel cut, maybe...
Iridiums plus are great! They'll help with the power and throttle response too. You may not need colder plugs with 9 psi, just check periodically the plugs and you'll know. Driving style also helps... a lot!
my 2 cents

 

[BlkZoomZoom]

Yeah some hesitation is gonna happen on a basically stock MSP...on a good note though once you go past 12psi the hesitation is replaced with tire spin!!!!!

 

[EvilMSP]

Yes open loop drowns the car but you can control it easily with a well trained foot. You just can't floor it, especially in certain RPM's. If you go with a smooth roll into the power there wont be any hesitation. Or atleast it can be controlled.

 

[Glowmunkey]

Yes open loop drowns the car but you can control it easily with a well trained foot. You just can't floor it, especially in certain RPM's. If you go with a smooth roll into the power there wont be any hesitation. Or atleast it can be controlled.

Yeah, I can attest to this... but it's still not cool.

And everyone, it is NOT heatsoak... stop suggesting that.

 

[EvilMSP]

Well actually heatsoak is to blame in some ways. Cause when that happens your turbo charge is not as good, and your not making as much power. So when you jam on the gas, the car goes into drown mode AND you have less power to eat up that stuff. So in some ways when driven "wrong" there would be more hesitation with soak then without. Anyone else agree with that theory?

 

[Dr.Sound]

yeah, for sure.
that's why hesitation is almost invisible with FMIC or upgraded SMIC.

 

[jonbig]

yea i mean when i drive my car in the morning when its cold, it doesent hesitate..pulls like hell, but when its hot its hesitates a little bit..guess that wil change when i put in the FMIC