I have a 96 impreza sti import
when putting my foot down the car gets to about 5000 revs and starts to splutter and not go any further which i can only describe as the car is choking ive asked a few people and had a mixed response a few are
.fuel pump
.injectors
.the fact my exhaust isnt straight through
.air filter
but i seriously dont know, Any help would be apreciated
many thanks

 

Possibly limp home mode.
Does the CEL illuminate on the dash?

 

As it is an import could it be that the car has not been re-mapped for UK fuel. JAP fuel is 100 RON our super unleaded is 97 to 99 RON. So it could be detecting det and cutting back to save the engine.

 

its had a remap and its currently an open remap or so i was told by the bloke i bought it from

 

If no cel light is showing it's worth cleaning the boost solenoid hoses & check the ends of the coil packs aren't cracking up under the boots. When were the plugs last changed?

 

Had the same problem with my import same year as yours and it turned out 2 of the coil packs were cracked.
That was about a year ago still no sign of hesitation.

 

The early cars can only be remapped by the addition of and extra chip, daughter board or piggy back ecu.

Speak to the guy who sold it to you and ask for a recipt on who mapped it (and how they did it).

Or find a good rolling road (preferably someone who has experience in imprezas) and pay £50 to see what is actually happening (after you check the plugs/coilpacks as you can do that )

 

+1 I had the same on a MY95 wrx. Changed the coil packs and she was fine.

Buy new not secondhand

 

no CEL?
IIRC, when MAF is totally dead or just unplugged you'll get the same 5k rpm limiter :roll:

 

ill take it CEL stands for check engine light ?

 

Yes

 

Yes, CEL = check engine

how does is behave under 5k rpm? how does it drive off-boost?

it may be a fuel pump which cannot supply enough fuel under boost and high rpms
it may be coil packs which cannot supply current enough for a good bang
it may be mass airflow sensor dead, but in that case the car would drive like rough and spluttering at any rpms and off-boost also

i wouldn't put my money on exhaust or intake though

 

Even though the CEL isn't lit it maybe worth checking for error codes as you can do it yourself as the classic impreza has test connectors under the dash (they can be a bugger to find though as they may be taped up

Scoobypedia | Trusted knowledge for everything Subaru | Knowledge / Reading ECU Fault Codes

 

normally it drives totally fine boots perfectly and holds it but when i floor it it just chokes 5 to 6 rpm and struggles i cant seem to break 80 mph either as its choking and i dont want to try power through it however the CEL has come on twice i think but gone off again within a minute

 

If CEL has come on and then went off ECU must have recorded the error in historic error codes, so check for codes as myblackwrx says.