Car coughs and splutters on boost???

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FoRcE FeD GT-FOUR

New member
Its sort of as if it misses.but its the fuel.i dno if its fuel cut or not.sometimes wen i boost it hard itll sound like its missing.is this fuel cut??? another thort was that because its getting worse and worse...ie it happens more often.could it be the tvis shitting itself and the butterflys closing and opening...any thorts would be great
 
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FoRcE FeD GT-FOUR

New member
allright ive figured its fuel cut.this issue is frustrating me so bad.(im boosting 12psi) can someone please please please tell me were to locate the pressure line to block off that feeds the ecu for the fuel cut
 
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FoRcE FeD GT-FOUR

New member
how will it blow up my car??? i know wat im boosting and it doesnt spike..so it should be good wouldnt it???? can someone tell me were to find the pressure sensor
 
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tw2

New member
Don't take this the wrong way but if you ask for help it would be nice to write in clear concise sentences. If you have fuel cut the sensor is located behind the ac idle up which is what it sounds like you have found with the big knob. Anyway from the RHS of the intake manifold 2 small vacuum lines come off and one has a filter in it. Follow this behind the manifold and up to the pressure sensor. If you want to just get rid of the fuel cut just take this vac line off.

As has already been said, if something breaks, a hose comes off etc then you will have no protection from overboosting unless you catch it yourself. DO NOT undo the electrical connector to the pressure sensor or remove it or you will still have fuel cut but with a vengance at sometimes random psi.
 
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FoRcE FeD GT-FOUR

New member
ok.i have noticed that the turbo pressure sensor is not hooked up...under the sensor were the vac line should be there isnt one....but i still have fuel cut...could it be cos its not blocked off?
 
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tw2

New member
The sensor vac line does not need to be hooked up or capped off to avoid fuel cut. As long as the electrical connector is still there you shouldn't have a problem. Check your codes to make sure you do not have code 34 and/or 35 which will be due to a short or open in the curcuit and too high boost pressure.

Fuel cut will throw you forward very forcefully at 12psi as soon as you hit it and will cut all fuel if you try to go above 0psi until you restart the car. The code will still be logged though.
 
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FoRcE FeD GT-FOUR

New member
the 2 codes it brings up is 22 and 51....what happens is only sometimes and wen it happens is around 7psi but sometimes it will be higher.its not boost cut.i know what thats like...hitting a brick wall...its not that
 
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BriinumsBo

New member
did you fix your problem?
I have the same hesitation. It occurs seldomly when i boost. What i`ve noticed so far:

1.changing plugs didnt do nothing
2.changing fuel filter seemed to fix it for week (maybe i have junk in gas tank)
3.its not that boost dependant, more throttle
4.after long drive (like 50km) at some 120km/h this becomes very possible - i switch into 4th gear to overcome someone and the car just doesnt go as i press the accel. going fast for long time makes engine bay pretty cold, dont know if that matters.
5.after turning car off for 10 mins (after the long drive), then starting back up - cannot get hesitation again!
6.doesnt matter if tank is full or empty
7. gas - 98/95 - doesnt matter

wires, rotor and cap not changed YET
also could be injectors all in dust..
 
M

muneo

New member
2 things to check:

-Pop open your Distributor cap and look for oil collecting on the lower plug contact.

-Also, I noticed a correlation between being too low on oil to my cars bogging problems. Check your dip stick a minute or two after you shut off your car. That seems to be the most accurate oil level.
 
2

2RM

New member
+1 on that muneo. Get a good boost/vac gage. Its a must! Vac leak are very common. They would make you car run like crap. There is also a high possibility of boost leaks. Check your IC hoses. They are know to dryout and become brittle over time. If that doesnot help make yourself a boost leak tester. The instuctions are here just do a search. Some boost leaks start only over 5,6,7psi and could not be detected without that leak tester. Make sure you pull the falt codes. Sometimes the AFM go bad but it should bring the Check Engine light on. Also when you hit a fuel/boost cut it should bring the Check Engine light on and would not let you boost pass 2psi but after you turn off the engine in should reset it. You will hit fuel cut again if you go over the "safe" boost pressure. So it is not a one time thing.
 
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BriinumsBo

New member
fixed my problem changing everything - rotor, cap, plugs, wires. i guess the wires were f'd up, one had oil on it!

boost gauge is a must! unfortunately i got it too late. my service put bad hose from turbo to actuator, which led to 1.1bar boost, now the motor is dead for already 2 months, hope to get it in a few weeks :(
 
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