Horrible hesitation

[Titanium-99]

Today while I was driving my MSP to work I decided to have a little fun as I always do on an open stretch of road. So there I am cursing in third gear and decide to punch it so I do and the rpms start to climb, they get to about 3 1/2k and all of the sudden it feels like my car is about to stall and it starts lunging forward like it would do if it wasnt getting any air or fuel I also almost loose control of the car once this happens so I back it off and put it in 4th and try to punch it again and the same thing happens at about 4k rpms. Well the Mazda dealer isnt to far so I decide to take it there, and me and the shop foreman take it for a real quick spin and the car dose it again and the foreman get's this look of death on his face and says oh s*** thats not good. So as we are pulling back up to the shop he says lets pop the hood and take a look, that it could just be a turbo hose come loose or possibly a hole in one of the hoses but he finds nothing and says thats weird I dont know what it could be, but that he wanted me to leave it there and they would get it fixed so I did and they give me a rental and I leave. Now I am scared shitless because I dont know what it could be. I dont have any mods and I havent had any so I dont know what to think. My car is still under warranty but I am still worried about the fact that I dont know what is wrong with it. If any one knows what this could be please let me know.

 

[jersey_emt]

Sounds like you just hit fuel cut.

 

[Titanium-99]

what would cause that?

 

[jersey_emt]

The cooler temperatures most likely. Do you have any mods done to the car?

 

[Titanium-99]

no I do not have any mod's nor have I had any. now today so far is the coldest day this year in texas with the high at 54 this morning and it started dropping from there at around 8:00am. I think currently we are in the 40's.

 

[jersey_emt]

Shouldn't be cold enough to be hitting fuel cut on a stock car, unless there's a leak in the wastegate hose which would cause the boost to be raised.

Could also be a bad MAF sensor.

Tough to troubleshoot when you don't have the car in front of you

 

[Aaron]

do you have a boost gauge? if so what were you reading? Mine is boosting 10psi stock and the first dealer i took it to didn't do s***. I am going to another dealer next week.

 

[Titanium-99]

I don't know bro all I know was it want good. its almost like the engine was choking

 

[jersey_emt]

Felt like you hit a brick wall?

 

[Titanium-99]

nope no boost gage.

 

[Titanium-99]

yes it felt like I hit a brick wall.

 

[jersey_emt]

Definitely fuel cut. It should not be happening on a stock car. I would make sure they checked the wastegate hose for leaks, and tested the MAF sensor.

Fuel cut happens when the MAF sensor clips (reaches or goes past it's maximum value of 5 volts). The MAF sensor measure the amount of air going into the engine, the more air, the higher the voltage. If too much air is measure by the MAF, the ECU doesn't know what to do, so it shuts off the injectors to prevent damage to the motor.

 

[Titanium-99]

HMMMMM that could very well be happening but like you said its a stock msp and i havent touched a thing under that hood I wonder if the MAF is possibly gone bad and not reading correctly.