megasquirt - still wont start

[jondrift]

after months of troubles, my car still wont go!

just had the ecu tested and its fine. my last problem was only 3 out of the 6 injectors were working, but now they seem to be all fine, however i now have quite a week spark. Th car turns over but wont fire. oh and its the coilpack not the original dizzy.

any ideas?

[FlappySocks]

Are you using thick enough cables running to the coil pack? Have you got the firing order correct?

[jondrift]

the cables were supplied with the coil pack, and the firing order i have goes like this:

624
153 (if coilpack plug on this end>)

[FlappySocks]

This is how I have done it.

Coil Pack Plug:

Code: Select all

1 (A) Cyl 1 6 (nearest to 4 pin connector)
2 (B) Cyl 5 2
3 (C) Cyl 3 4
4 +12v

Hi res: http://farm2.static.flickr.com/1245/133 ... 1a71_o.jpg

I got the 12V from the original coil connection.

[jondrift]

it looks like your ht leads are slightly different may be? my pin four is wired to the old coil, then 1,2 and 3 are wired in an order ant gave me to a,b and c on the megaquirt, then there is an earth on that loom too. as far as firing order goes, this is how mine is:

[FlappySocks]

Maybe my A,B & C are different.

You are getting a spark, you say, but a weak one? What about the fuel pump?... can you hear it start up when you put the ignition on? Got your foot on the throttle to give it some air?

[jondrift]

i take it yours is running right!?

[jondrift]

it has next to no spark, then evry now and then it does one big one..as for the fuel pump, it definately works, there is loads of petrol flowwing through it!

[Gunni]

are all the leads showing spark?

Are you using the correct HT leads?

[FlappySocks]

Mine runs great.

How do you know if has next to no spark? Have you seen/measured it, or you mean it's just not firing? Could be your firing order is wrong and the engine id flooded, or could be an incorrect parameter in megasquirt.

[jondrift]

i held the plug on the block and watched it, and there was nothing for a few seconds, then one big one, then nothing again?? im using the standard 325 ht leads. to be honest thou, i only tried one lead

if the leads are in the wrong place on the coilpack, i take it it wont fire? will it affect the spark strength??

[FlappySocks]

if the leads are in the wrong place on the coilpack, i take it it wont fire? will it affect the spark strength??

It will fire, and it wont effect the strength (assuming you have 12V on pin 4). Are you sure you have MS configured correctly? Is MS grounded properly?

[Gunni]

nothing for a few seconds?
what are the crank rpms in the megalog viewer.
sounds like a crank signal issue,

it shouldn´t affect spark strenght.

[jondrift]

what will the wrong order actually do then? i definately have pin four on 12v. The megasquirt is grounded using the original ecu ground. As for configuring it, this is quite hard as i dont have acess to the laptop all the time

do i have to calibrate the tps every time the ecu is unplugged?

what else do i have to configure after pluggin it in before i can turn the key!?

[Gunni]

are you running it wasted spark from a single 60-2 wheel?
or sequental from a cam sensor as well?

#1. Check if you are getting spark on all leads.
#2. Check that they are getting the signals they are supposed to.

[jondrift]

im afraid i dont know the answer to that! I guess it would help if i knew what i was doing! lol all i know is the coilpack looks like the one in the above picture and its using the original crank sensor i think?

dont suppose anyone on here does call outs? im getting to the point were im willing to pay well to get it running as its been soo long!

[FlappySocks]

what will the wrong order actually do then?

Backfiring, erratic firing.

do i have to calibrate the tps every time the ecu is unplugged?

No.

what else do i have to configure after pluggin it in before i can turn the key!?

Everything!

Where are you?

[Gunni]

So this ms unit hasn´t been configured yet?

[jondrift]

all ive done is got it out the box from ant, wired it into my car, calibrated the tps and thats it.

it has a basic map on it from ant, i presumed this would work? Im taking this really isnt the case then!!?

im near silverstone....

[Gunni]

you really need to begin with checking that you are getting spark from all leads.

[FlappySocks]

It should be configured to work then. If all the spark plugs are behaving the same way, then i'd go with Gunni's suggestion, being a crank signal issue.

[jondrift]

ok, ill have a good check tomorrow, i know the trigger wires are ok, as i do have an rpm reading on the laptop. It could well just be a case of it being flooded from all my failed attempts!

[Ant]

check the coil ground, coil drive A B and C to pins 123, pin 4 to +12V (edited, must not drink and post lol ))and the extra wire from the Db25 conector to a good ground, no good ground, weak spark

the unit is 100% tested under soak conditions and the map is from a car of similar spec with all the same options enabled

the coil dwell is setup as per my car so there should be no issues there Jon.

I feel for ya dude, it WILL be a wiring glitch, it always is.

[Speedtouch]

You soaked it?! No wonder it won't work...

[jondrift]

thought pin 4 goes to 12v? i have put pin 4 from the coilpack, to the original coil 12v, and not touched the ground on the original coil. pins 1 2 and 3 are on the blue white and grey, and the black one on that connector is on my suspension bolt.

are there any diagrams anywhere just so i can double check everything??

[Ant]

my bad, pin 4 is 12V, original post edited

the MS loom has 3 coil logic drives in it, ABC, the other is the ground loop that should go back to the strut top as you've already said

to make it simple, put the dizzy cap and rotor back on and disable coil driver B and C ( in the output section on MT ), then see how you get on maybe Jon ???

[jondrift]

ok, thanks! fingeres crossed this will get fixed soon!

[jondrift]

hey just had an electrician guy out and we tested everything. we have found out that on the coilpack, only the two pins nearest the connector are generating a spark. The other four are not at all. All the wires in this circuit are fine, with a good earth, power and all have signal. Im guessing therefore its the unit itself. Does anybody know what car its from originally??

thanks

[Ant]

vectra or omega V6 coilpack dude

pinout is the same as you have now, avoid the ford ones, NFG

[FlappySocks]

Has MS been reprogrammed since it was originally programmed by Ant?

Check these settings.

[Ant]

Its just been back to me Stuart, all settings are correct for the application.

[FlappySocks]

oh, ok. I had a brainwave that maybe it was inadvertently reprogrammed back to a single coil setup when the TPS was configured.

[jondrift]

ive swaped the wires about thisafternoon, and the grey wire on the coil loom is working, and therefore fires the pins whatever pin it is hooked up to. this suggests that its probably not the coilpack. The blue and white wires dont seem to work whatever pin they are on??

could it be a bad earth?

[Gunni]

so you have 3 signal wires to the coil packs?

and only one signal wire is working?
and powering two coils.

You need to measure continuity from the beginning of the loom to see if it´s inside the ecu or not.

[jondrift]

yea thats correct, althought the ecu has only just got back from being tested with ant, so in theory it should be ok... im also stuck with which wire is which when it comes to a,b anc. i have blue, grey and white going to pin 1,2 and 3, but i cant remeber which colour is which (blue=sparkA etc) think only ant would know that thou as its not standard loom!