94 WRX Electrical Issues... IVE HAD ENOUGH ITS ABOUT TO GO OVER A CLIFF

[Guest lan_killa]

Hey guys...

You may remember i had a thread up here sometime ago about electrical issues in my WRX, well we never got them sorted, so Im going to ask again.

Problem:

Looses spark randomly, but only when warm if driving in the middle of the night it runs mint, middle of the day... not so flash. This is not a missfire it is a complete and total lack of spark. Will do it at any time, idle, deceleration, acceleration, cruising or even wide open throttle. Duration of loss of spark can be anywhere between 1 second and 30 seconds, sometimes it wont even restart. Very occasionally i will get a CEL which comes back as air flow meter, but i dont get it every time.

Remedies Tried:

-New AFM

-Second hand Cam and Crank angle sensors

-Second hand ignitor

-New Coils

-New Plugs

-Additional earth leads from battery -ve to block and inlet manifold

-Additional earths for the ECU from the inlet manifold. (as described on the last page of the possum link installation manual)

-Second hand TPS

-Have sprayed contact cleaner through every last connector I could find

-Have found that I can unplug the AFM and it stops this cutting out nonsense, but then ends up in limp mode and doesnt run particularly well.

Please help me with this... I have really really had enough of this, its been going on since easter last year... am seriously over this car, want to get it running and sell it so I can get something else, in its current state it will never sell as I can barely drive it to work and back.

[Guest]

ill find you a cliff

-smurff

[Drunkenmonkey]

what about interference in a sensor wire with a broken shield? have yo checked resistance of the wires for major things might be a partial break somewhere?

[Guest]

does the dash still light up etc, just no go?

theres the temp sender in the airflow meter? ( dont remember for sure ) cable from that damaged?

just thinking of the temp thing in that coz you motioned ok at night coz its cold at night lol

-smurff

[Guest lan_killa]

when things are cool (ie night) it runs mint... when its a warm day its a complete sack of ****...

dash still sits there doing its thing, have noticed when it stalls it takes a good 4 or 5 seconds before the CEL comes on after stalling

BTW this doesnt make sence

 

theres the temp sender in the airflow meter? ( dont remember for sure ) cable from that damaged?

[Guest]

whic ecu you hav in there atm?

-smurff

[Guest lan_killa]

a factory one

[Guest]

any idea why ur abs threw a wobbly?

was about your map sensor? that could cause to run bad and if i unpluged mine ( the electrical plug ) it would stop the car.

-smurff

[Guest]

yes, im taking pot shots here lol

-smurff

[Guest lan_killa]

abs is always odd when you activate it in my car... it is and older setup and uses a g-meter to determine what to do.

dont think its map... if i unplug a vac line i just get limp mode

[kamineko]

double checked all your earths?

[Guest]

u could try running a new power wire for the coils? my leone did this sort of thing and that sorted it, although it is a very basic setup compared to this. you really need to do some tests as soon as it dies to see if it is a power issue etc .. but running a new wire will at the very least eliminate it as the problem

[DRFVDR]

water temp sensor ???

running in excess fuel mode all the time cause it thinks its cold

[Guest lan_killa]

should have more than enough earthing now

the Leone and the WRX are very very different beasts wiring wise (i used to have a leone too) remembering I have 4 coils and each coil has 2 wires to it

Dont think its water temp, ive had logging software on it, and can produce a log if you like and the ecu reckons the water temp is around 95degC once at normal on the gauge

[Guest]

has it been logging when the problem happens?

-smurff

[Guest lan_killa]

yeh... have a couple.. will dig them up tomorrow

[Guest lan_killa]

ok heres a log for you to look at

http://homepages.slingshot.co.nz/~moliver1/WRXbad130210.csv

Points where it stalled

------------------------------------------------------------------------------

Car was sitting idleing in driveway

LogID 101 looks to be where the stall started to occur

LogID 104 - 116 note RPM showing 225 (engine was deffinatly stopped)

LogID 117 Restarting engine

------------------------------------------------------------------------------

Just after reversing out of driveway

LogID 144 - 145 Car stalled

------------------------------------------------------------------------------

Started driving off down road

LogID 162

------------------------------------------------------------------------------

Theres a few other weird things in that log which you may pick up on.. but having a quick scroll through is seems that the knock correction is all over the place... 17 at idle yet was down to 1 at LogID 269 and was up as high as 45 at times

got ignition advance of 31 at LogID 141 and upto 45 at times

[Guest boostin]

Are you sure its coils losing power? The AFM shares its 12V supply with the injectors. Maybe that feed is dropping out?

Just an idea, run a few leads back into the cabin with some LED's connected to things like AFM 12V, coil 12V etc, so if it does die, check the LEDs to see what has dropped out.

An issue that comes and goes with temperature usually indicates its a connector opening up and breaking contact. Have you done the wiggle test of all the connectors in the engine bay?

[Guest lan_killa]

that led idea sounds like a plan

its hard to tell with the wiggle test as its an intermittant fault anyway...

Got a pin out for the green afm?

[Guest boostin]

Yeah I do somewhere..... But where....??

[Guest boostin]

Found it!!

1. Yellow/blue - 12V

2. Black/green - Earth

3. Black/green - Earth

4. Pink/blue - Signal

5. Yellow or yellow/red - Air temp

Both earths link back together and run to the ECU.

[Guest lan_killa]

ahh hah... mint

so what should I be putting LED's across??

-AFM

-Coils (or ignitor?)

-ECU

-what else

Oh and today i changed alternators to a spare one I had floating about... did notice that my stereo doesnt whine when the alt is disconnected, but when an alt is connected and the car running the stereo whines quite a bit

[Guest boostin]

I would go AFM, ignitor and coil, and injectors. I say ignitor and coil as it will check the connector between the 2.

[Guest lan_killa]

ok, so you reckon just take the +ve side of those to the LED and use a common earth between them?

[Guest boostin]

Yeah that should work ok. Just make sure you use resistors with the LEDs!!