Miss accross the rev range

[WRXONP]

yeah man injector blocked or just not opening will cause miss fire. pull a coil at a time to figure out which cylinder . could be coil wiring ns injector wiring . using a light or multi meter you can probe injector wiring to see if injector is getting a pulse

[Pappu1]

 WRXONP said:

yeah man injector blocked or just not opening will cause miss fire. pull a coil at a time to figure out which cylinder . could be coil wiring ns injector wiring . using a light or multi meter you can probe injector wiring to see if injector is getting a pulse

thats the current plan.. im hopong like hell its a dud coil that i put in (just can have an easy time)

the injectors are covered by some damm metal paltes so have to figure out how to get them off lol

i could reach 1 injector and while trying to make sure the plug is on tightly, i say that it was able to rotate (top feed) a bit

is that normal?

i was under the impression that injectors needed to be rock solid in place....

[WRXONP]

na you should be able to swivel a top fed injector . .

[Pappu1]

haha thats a relief..

ok wud u care to guess why wud the car run ok for 1-2 seconds when u start it up and then start the miss...

does that point blocked injector...??

or a dud fuel pump.. im thinking what if its like this - fuel pump primes ok but when gets a bit of load - cant cope (even at idle??)

[soopersubaru]

 pappu said:

haha thats a relief..

ok wud u care to guess why wud the car run ok for 1-2 seconds when u start it up and then start the miss...

does that point blocked injector...??

or a dud fuel pump.. im thinking what if its like this - fuel pump primes ok but when gets a bit of load - cant cope (even at idle??)

Air Flow Sensor!!!!!!!!!!!......................Put a pressure gauge in the fuel line after the filter under the bonnet if you concerned about pressure loss ............Should be around 2 bar at idle.

AFM>AFM>AFM

However also note your Smoke comment.............Get a compression test done....This will find a cracked piston/rings........IF the mechanic knows what he is doing and has the correct tools.

After market open blow off valve fitted?

[boon]

If you're getting blue smoke then it's burning oil. White/blackish smoke is just unburnt fuel but if it's that telltale blue (like a 2-stroke) then I'd be looking pretty hard at your piston.

Do a compression test?

[WRXONP]

if its grey black smoke then you have ignition failure . the smoke meaning the injector is working and pumping fuel in and no spark to ignite it. when you pulled plugs was one black or wet ? or they all the same ? if blue smoke then as said above oil is being burnt. when it first started doing this what were you doing ? cruising or raping it ?

[Pappu1]

one of the plugs was black as lol

so im guess that one may have had issues

the smoke was seen in night so i will do another test in day..

i swapped afm with my brothers and made no difference

i was stopped at a set of lights when it started doing it..

for the 20 mins before was crusing in a 50 zone so pretty much no boosting

just in case its rings gone - what are the symptoms of gone rings?

[WRXONP]

one black plug indicates ignition failure like i said . . remember which cylinder it was ? the black indicates you have fuel and no spark or compression . but you have fuel. pull the plug and test for spark. earth spark plug thread on motor and put coil on and crank motor . you should defiantly see the arc jumping the plug gap . if no spark then look into that cylinders ignition . . check the coils signal wire for pulse etc

[soopersubaru]

 pappu said:

one of the plugs was black as lol

so im guess that one may have had issues

the smoke was seen in night so i will do another test in day..

i swapped afm with my brothers and made no difference

i was stopped at a set of lights when it started doing it..

for the 20 mins before was crusing in a 50 zone so pretty much no boosting

just in case its rings gone - what are the symptoms of gone rings?

Time for a compression test......Cracked ring/piston fraid to say....My guess anyway. :'(

Think you have the symptoms............black plug.......no burning occurring!

[WRXONP]

check ignition first lol . . . can be dud coil. dud plug . wire fault . ignitor fault . . . 1st thing 1st check your spark plug is sparking !

[soopersubaru]

 WRXONP said:

check ignition first lol . . . can be dud coil. dud plug . wire fault . ignitor fault . . . 1st thing 1st check your spark plug is sparking !

Bog off..Might as well do comp test.plugs out ...easy.....Not an electrical miss.........smoke too....you dont get much smoke with an electrical miss............Not very well described to start with...its missing across the range

[WRXONP]

you got some sort of problem with me Fuck face ? every thing i say you dis agree . . . a black plug indicates its not sparking and burning fuel. . . if the spark isn't sparking them YOU DO Get smoke as the raw fuel doesn't ignite via the spark plug . it normally ignites off exhaust . . . excessively rich when the plug doesn't ignite it

[soopersubaru]

 WRXONP said:

you got some sort of problem with me f*** face ? every thing i say you dis agree . . . a black plug indicates its not sparking and burning fuel. . . if the spark isn't sparking them YOU DO Get smoke as the raw fuel doesn't ignite via the spark plug . it normally ignites off exhaust . . . excessively rich when the plug doesn't ignite it

True!.....Black plug no firing of fuel or at least limited....Engine not rocking like crazy at idle,,,therefore compression related..........i did consider AFM earlier.....but now the smoking...................you get hardly any smoke if at all from an ignition/electrical miss..............Sorry i just don't have much time for idiots..therefore will always disagree

[Pappu1]

update:

changed all 4 coils and 4 spark plugs and air flow meter

same issue

when starting the car for 2 seconds sounds rather normal and then the missing starts

while i had the the car running (approx 10 mins), i had the oil cap and dip stick out

a educated guy told me that if its broken rings, there will be some smoke comming outta the open cap - none whatso ever came

(doing a compression test in weekend hopefully to confirm)

also while car was running i took off the coil wire on each cylinder. here is what happened:

taking either of the drivers side coils make a significant change inn the miss sound and makes it worse.

taking either of the passengers side coils makes almost no difference to the miss sound

give or take its a very minor difference.

in fact taking off both the passengers side coils makes little very little difference

strangely, if i remove one of the drivers side coils the mis goes real bad (while the passenger side coils are removed as well) but putting in either or both of the passengers side ones makes a slight difference

questions -

what wud cause both the passengers side ones to be so bad in not performing (will repeat test with another set of coils but i dont think it will make a difference as the set i changed to was a known working set)

also,

would the cam position sensor be causing this - im thinking if the cam position sensor has gone bung then will the cams go to full retard and will that cause miss type issue (just asking as im not sure myself

ideas ppl...

assuming the compression test comes good - what else could it be... ??

i will also remove the passenger side coil and spark outside to see if it is sparking.....

[DRFVDR]

Ignitor ?? or ECU

[gazzy2000]

 DRFVDR said:

Ignitor ?? or ECU

yea borrow an ECU before you dig too much deeper

[Pappu1]

 gazzy2000']

[quote name='DRFVDR said:

Ignitor ?? or ECU

/quote]

yea borrow an ECU before you dig too much deeper

ok bro.. will try that too....

will get my brothers ecu as its known working good ecu and will swap over

(lucky we got identical cars so can keep borrowing known working parts to test lol)

ignitor - - where do i find that on a v7 sti?

assuming that aint a issue - any more ideas?

[gazzy2000]

 pappu']

[quote name='DRFVDR said:

Ignitor ?? or ECU

/quote]

yea borrow an ECU before you dig too much deeper

ok bro.. will try that too....

will get my brothers ecu as its known working good ecu and will swap over

(lucky we got identical cars so can keep borrowing known working parts to test lol)

ignitor - - where do i find that on a v7 sti?

assuming that aint a issue - any more ideas?

i think the ignitor is built into the coil pack itself on those.. ie a igniter on each pack

(dont forget to disconnect batt when swaping out ECUs

[boon]

Passenger side has no compression maybe? Headgasket, timing issue, bent valve? Just throwing out some ideas here. I think the compression test will tell you a lot.

Or maybe some sensor on the passenger side related to timing?

[Kiwi_Fozze]

yeah im starting to think broken wires somewhere? or ecu giving up? bad tune?

[Pappu1]

i will open and replug all the connectors.. hmm lets hope its the ecu thats dying hehe

been reflashed a lot of times in the testings i have been doing

na the tune is good as been tested but could be only so many times a ecu can be reflashed before it decides to die..

lol have spare ecu to put on so hopefully thats the case..

i really really home the compression test reveals no broken rings

otherwise :'(

[Kiwi_Fozze]

as far as im aware, the 16bit ecus will handle over 1000 flashes before you start getting into unknown stuff.

32 bit ftw, they will handle over 10,000... or so i understand.

[funkytown]

given the nature of your tuning all the time,

not that im dissing it, but its not factory, therefore their is increased risk and chance for failure.

il assume you have tried factory ecu's already.. if not why not.. Id be looking at doing the compression. Its the logical next step to give you a litmus test on the health of your inner motor. Then is spark and wiring.

[Pappu1]

mine is 16 bit ecu hmm not sure how many reflashes i have done but i always test out all the little things a lot

been very careful not to mess with any of the running parameters but changing timing and avcs and the likes etc

there has been very little det on the engine so really hoping no ring failure but then its not exactly new engine so never know what previous life was like...

anyway

yep ok plan is set like this now -

try reconnecting all the connector plugs FIRMLY

if that fails

try a stock ecu

that fails

compression test

if that passes - smile and re look at all the wiring one by one

if the compression test fails - cry like a little girl

sounds good??