Running problems
 

alright lads, relatively new to the site and to scoob ownership and so far i aint best pleased due to the fact the day i got it home its started running like a bag of nails... intermittantly!!

when driving (engine hot or cold) it coughs, splutters, misfires, surges, reeks out black smoke and sometimes there is no throttle.

i checked and found 2 codes:

23 - MAF
32 - Oxygen sensor

replaced both and also tried another ECU but the problem still there. i have visually checked all pipework and vacuum hoses with no obvious issues. its really bugging the sh*t out of me. I have been assured that this version doesnt have any issues with the coilpack going down but being a mechanic it feels like it

ANY IDEAS??

its a Ver3 WRX wagon fresh import with no mods whatsoever

failing ignition should not result in the MAF errors.

if you already changed the MAF then check all the wiring to the MAF sensor.
A faulty wire would explain the intermittant behaviour and ECU errors.

plugs and coilpacks to start with

couldn't hurt to check ignition offcourse but I was talking about the wires to the MAF-sensor.
Just check if power and ground is constantly present at the MAF connector and check if the maf signal is always available at the ECU (or better yet check continuity of this wire)

its the black smoke that is pointing me in the direction of the plugs or coilpacks.

black smoke means it's running excessively rich.
which means air fuel ratio is wrong.
which can be caused by the MAF not by the ignition.

other possibilities are injector is sticking or fuel pressure is wrong.

thanks for the replies. when u think about it it could be either.. as sl1000 said the MAF would cos upset fuelling BUT if the coil is faulty then there would be no spark so no burn hence black smoke and not necesarily over fuelling. it cant be plugs as it is intermittant and this version has the single coilpack with plug leads and again when u feel the symptons it doesnt feel like a failing lead either. bit of a head pickler really. will check maf wires tomorrow and gonna see if theres a V3-> in my town that i can sweet talk into a shot of their coil pack

that was my thought exactly, just couldnt think of the right way of explaining it if that makes sense.

last night - replaced the FPR vacuum pipe as it was split and had the battery disconnected while doing it to erase the faults, took it a run and was going great for longer than normal then BLUH, started running crap again. misfiring, black smoke, hesitating, back firing and idling at 500rpm! no ecu codes. i pulled each lead off individually from the coil to see if it was the coil was going down but it got worse each time and it was sparking away! so just left it for the night. jumped in the car to go to work this morning and was doin it straight away and when i pulled up at work it was hunting from about 700 ish to about 11-1200rpm. after work it wasnt half as bad just minor splutters.....

im baffled

anyone got any ideas?

anyone?