hi folks im new to all this forum stuff but need some technical help.
just bought my first impreza 6 weeks ago,which the last 3 it has been in extreme motorsport,where the guys have carried out every test possible and come up with nowt.
here goes!
the car is lumpy on idle,miss fires and runs extremly lean.
so far parts that have been changed are lambda sensor,spark plugs,ecu,maf sensor,coil pack,leads all fuel lines and fuel rails have been cleaned out.
under load the car is not getting enough fuel on 3 cylinders every test carried out onthe car has come back in conclusive this car should be perfect!
forgot to say its a 1998 version 4 type r sti
this really is getting me down,dont know how much of this i can take.....

 

fuel pump?

 

Have you had the injectors cleaned.

 

fuel pump is fine was removed tested and refitted,injectors are next on the list but i was told its very unlikely for 3 to go at same time?????
i need to pin point this my bills getting to the £500 mark and the car aint any better yet.......

 

Any modifications to the car?

Tony

 

as far as i know the car is pritty standard,its got exhaust, uprated fuel pump dont know about the ecu?? but i have changed that now and its not the ecu..
car is just not getting enough fuel,not even enough to spool up.
this started on trip to tesco at low speed.

 

If your fuel filter/lines have seen better days then you could have got some crap into your injectors and then yes 3 could give up at the same time. Same as if the inlet has been off in the past and not covered up properly and the injectors are dirty that way?? My money is on them mate, either that or the ECU you have put in is not the correct one for your car or has a bad chip? Thinking about it, it could also be some sort of short in the wiring loom to your injectors? Dont take my word on it but its just a thought...

 

But did they check the fuel pressure?

 

all the parts that have been changed have not made any difference the car still has the exact same problem.fuel pressure is spot on,fuel lines are spotless and have been cleaned through.
the only thing thats on my mind is that when i got the car the previous owner was running car on octane boost aswell as super unleaded,i asked john at extreme if the car needed the octane boost he told me super unleaded (v-max) would be fine,next time i filled up car i only used v-max it was then after 3 quarters of a tank later this problem arose........
anyone think this could be the problem??
could this have damaged the injectors???

 

A split or 'blown off' intercooler hose would cause missfiring and lean running.

 

PM sent,
Dave.

 

hi guys turns out it was the ignition amplifier?????????
so now im £750 lighter for the 4 weeks it been in extreme
motorsport,but atleast its on the road

many thanks for everyones help

 

Wheres the ignition amplifier
Cheers,
James.

 

knock sensor?!? or a leaking dump valve for idling?

 

ehh dude he seems to have solved the problem

 

your a smart 1 aint ya!