03.5 MSP bucking REALLY hard

[03.5_MSP]

Well not much to say other than my car is completely stock accept for boost guage, I did have a boost controller on it but I took it off a while ago and it just recently started bucking really F****** hard and I can't figure out why the heck it's doing that, whenever it's under boost it just starts bucking like crazy and will not stop until I let off the gas. It definely does not feel like stock boost tho, the turbo really spins up and pushes you back in your seat like crazy but I dont' understand why it would be pushing 12psi if I do not have a boost controller on it?? I'v messed with my boost controller before and had it where it was pushign close to 12psi and it would start bucking and i knew it was cutting off the fuel so I turned it down and it has alway been around 7-9 psi nothing hgiher, and all of a sudden it just started doing this....I can't figure out what the heck it's doing. maybe you guys can sshed some light on this. Thanks alot!

 

[Fudgie]

Double check your vacuum/boost hose connections going to the wastegate actuator. Sounds like fuel cut. If those are ok, may need a new actuator. Boost guage 12 psi when it cuts?

 

[Brian MP5T]

Fuel Cut. It's getting colder..

 

[Ryoga28]

Check your vac hoses for any leaks or breakage.

High boost plus fuel cut....needless to say what would happen.

 

[orng1]

Yeah I'd say fuel cut, I've only hit it once the whole time I've owned it and it was real cold that night. What are you boosting when it happens?

 

[Ryoga28]

another thing to avoid fuel cut is to not drive the car hard. Be gnetle with it.

Don't get a fuel cut defenser, as there is a reason why the fuel cut was programmed.

 

[MSP608]

how come other turbo cars dont have to worry about fuel cut? is it bc they run something other than a maf sensor?

 

[Brian MP5T]

Mazda knows that the motor is only good for 7 Psi..

Dense air makes more power.

It's a type of protection.

 

[MSP_4_CODY]

yea fuel cut! same thing happend to my friends evo, the wastegate line popped off and it felt really fast untill it slammed you lol.

 

[MSP608]

Mazda knows that the motor is only good for 7 Psi..

Dense air makes more power.

It's a type of protection.

well the fs-de was never meant to be boosted in the first place. i know the denser the air the more power but its not the motor its the ecu that causes the fuel cut. how do srt4's, sti's, and evo's not have to worry about it. i hear the ms6 even hits fuel cut. should mazda just run a different ecu setup on their cars?

 

[MSP#735]

welcome to the "Fuel Cut" world...enjoy!

 

[SeR_Cyclops]

welcome to the "Fuel Cut" world...enjoy!

no joke its really annoying btw

 

[Jaysanooch]

another thing to avoid fuel cut is to not drive the car hard. Be gnetle with it.

Don't get a fuel cut defenser, as there is a reason why the fuel cut was programmed.

Ya obviously, but it just killed me to have a car that I couldn't drive the way I wanted. Be gentle ya, but fuel cut has also happened when barely pushing it. I couldn't take it no more...I got informed and slapped on a FCD with proper tuning.

Driving fast is stupid an dangerous no doubt but sometimes using the power to get out of dangerous situations is an advantage. Try hitting fuel cut when accelerating to pass on the left to avoid a stalled and no time to brake....well I did! I lost power and momentum and barely avoided the stalled car and the car who boxed me in. Last April...I'll never forget that.

FCD...ftw!

 

[03.5_MSP]

Well, I'm not sure what the heck I did, but I popped the hood and was moving my intercooler pipin around got back in the car and it only does it ONE time in second gear, almsot everytime around 3k rpm's it bucks a little bit and than takes off, no problem in any of the other gears tho, just second....kinda weird. Probably a vacuum leak I had somewhere, I don't have a boost controller or anything on at the moment. When it was bucking if felt extremely fast and all of a sudden it just start bucking realy effing hard. Not sure what it was but something to do with a leak somewhere in either a vacuum line or the turbo/intercooler piping.