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I wonder if this has massive effect on my misfiring issue :(

attachicon.gifBattery Voltage.JPG

well that aint right, so have you probed the alternator terminals ?

http://www.sau.com.au/forums/topic/442670-alternator-problems-some-answers-inside/

a little hard with all my pipe work and hoses in the way.. however I will pull it off after the track day and test it..

lucky car runs a map sensor so will run fine without any hoses attached

will report back :)

if that's the case will need to run new power cabling as suggested, however my battery is in the boot!!

a little hard with all my pipe work and hoses in the way.. however I will pull it off after the track day and test it..

lucky car runs a map sensor so will run fine without any hoses attached

will report back :)

if that's the case will need to run new power cabling as suggested, however my battery is in the boot!!

just crawl under the car and probe it

try running the 2nd power cable to the jump start terminal from the alternator if the factory cable is bad

Edited by Dan_J
  • 2 weeks later...

Why bother. As mentioned the ls coils have been tried and proven and are cheap.

No way would motorbike coils be cheap.

You would be surprised, motorbike coils are that dear, though I still can't find where it says these are motor bike coils, they look like Honda replacement coils, does anyone have a link to where we could that upgrade from :)

Scott at insight and I have discussed a coil upgrade for my 34 some time ago and he suggested Honda coils would be a good upgrade and would mean I wouldn't have to remote mount them or have to run leads

just crawl under the car and probe it

try running the 2nd power cable to the jump start terminal from the alternator if the factory cable is bad

Followed your advice, did a probe when cold voltage was about ~13.6 and down to ~13.2 when I revved it..

Tried it again when the car was hot (after a drive to the shops & back) voltage was around ~13 on idle and dropped to about ~12.8 when I revved it.

This is pretty consistent to the drop I've logged from my ECU.

Now to waste more money :(

Nice, got any more pics of that setup ?

not my setup but have all the bits to get it working :)

skim through the older pages of the thread to find the origin of the photo

Followed your advice, did a probe when cold voltage was about ~13.6 and down to ~13.2 when I revved it..

Tried it again when the car was hot (after a drive to the shops & back) voltage was around ~13 on idle and dropped to about ~12.8 when I revved it.

This is pretty consistent to the drop I've logged from my ECU.

Now to waste more money :(

yeah mine was a bit intermittent, after constant use the heat in the cable may make the power drop as well .

pretty cheap fix for myself:

$8- ba ford starter cable from wreckers

$5/10 - battery lugs from jaycar

keep the factory cable there and just add another positive cable to terminal in the engine bay to see if its a fix, if not will have to get a 2nd hand cable from a r33 wreck, welding store for the use of welder ground cable which i'm told is priced ok or ebay ;)

^ you're lucky it was just the power cabling.. I tested it on the alternator itself and the voltage was fluctuating...

I'm guessing it's tired, it is an 18 year old car with probably 400 000km on in after everyone having a go at winding back the odometer lol

I had some misfire on boost before I tuned my car last week, that cleared up after installing some ls2 coils I bought 2nd hand for 150 bucks, basically at the stock 2.5 ms dwell they were igniting a mix that was to rich for the stock coils to ignite, set up as coil on plug in wasted spark on an adaptronic 420d, trimmed the stock boot down and put em straight on the plug. Peice of aluminium angle with a few holes and all mounted nice.

After tuning on weds, I'm making 196rwkw with stock turbo, and stock injectors, only at a touch under a bar boost on shell 98

post-92228-0-54348000-1415354654_thumb.jpg

Edited by Scott Black
  • 5 weeks later...

Installed my kit from Rick B at Mojo Performance and the engine is not starting. A few things to note. I have a piggy-back HKS FCon V-Pro ECU that is already tuned. Fully built forged motor with billet crank, Bullseye 375R turbo boosting 2.2 bar, redline set to 9500 rpm, 270 degree 10.8mm lift cams, high flow head, 1000cc Sard injectors, NGK Racing (temp 8 or 9) iridium spark plugs. ECU is still set to stock dwell so I thought I would plug in the new LQ9 coils (Araparts version) and Mojo wiring to test before having my tuner mess with the dwell settings. Well, the car won't start and misfires occasionally during the attempt to start. Any ideas? Is my setup to aggressive for stock dwell? Not enough spark at stock dwell settings? Or is something else going on?

Your setup would have no affect when cranking, and stock dwell will work you coils pretty well, so setting is seriously wrong.

Have you checked voltage ar the coils? Was there another earth to install?

I'm not familiar with that kit, is it possible to connect the coil loom in the wrong order?

Edited by Ben C34

Your setup would have no affect when cranking, and stock dwell will work you coils pretty well, so setting is seriously wrong.

Have you checked voltage ar the coils? Was there another earth to install?

I'm not familiar with that kit, is it possible to connect the coil loom in the wrong order?

I thought the same (that it should start and run at idle at the very least).

No, I have not had a chance to check voltage at the coils yet. I need to do that. Yes the harness has it's own ground that I have connected/grounded along with the engine harness ground using one of the bolts for the mounting kit that screws into the head.

No, I don't think it's possible to connect the individual connectors in the harness in the wrong order. Also, the kit comes color coded and with a great install diagram to match up to the stock wiring. I verified the colors on all wires and they appear to be accurate.

I don't know anyone first hand who has used the LQ9 coils connected to an HKS FCon V-Pro ECU. Also, the cam timing is not zeroed out so there is some overlap at idle.

The Mojo Performance kit is a plug on coil setup and I have read that without the resistance of the plug wires or resistor type spark plugs that there could be an issue as well.

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