FINAL CONCLUSION AU3 COIL INTO EF:

So bottom line is that as far as AU Series 3 coil into EF goes it's an easy mod and works fine - the connector loom changeover is just same colours to same colours and away u go (thumbsup).

The problem I had with idle miss + stumble on takeoff + slight surging at cruise WAS BAD INJECTOR/s!! - it happening at the same time as I did the coil was just bad coincidence I fitted a set of reconditioned AU injectors and she's running fan-feckin-tastic!!! Idle with the replacement injectors is not quite as smooth / even as before, but there may be a bit of learning needed and my cam is something ove 500 thou lift so ANY richening by the new injectors will show - is probably more remarkable how smooth it idled before than how slightly uneven it is now.

In the context of people searching for those symptoms I should add that it had been running fine and smooth for the first few minutes from cold then the miss would appear - maybe ECU Choke mode masking the injector issue - which was evidently poor flow/spitting/streaking at low duty cycle? (keep in mind it was making max rpm and accelerating fine)

Well done Greenmachine on sorting out the miss you had, i have had same issue with my au for a while and after 3 coilpacks,new leads,plugs,fuel filter etc still no joy.The question i would like to ask is if say no1 cylinder spark is weak can no1 cylinder blocked injector affect the quality of spark on no1 cylinder? or its definetly ignition related,wiring etc. I hope its injector related as ive got a spare set of injectors. I know its no1 cylinder cause when i tested all the coilpacks got the same numbers (primary&secondary) even laid plug on cylinder head and saw weak spark from all coils tested. In the workshop manual, spec is 0.6 ohms, if over 1 ohm replace coilpack-mine all tested 1.2 ohms. Not sure if actually all coilpacks are gone or my multi meter is crap or its the injectors. Thanks for showing/demonstrating what options are out there for ef/au coil pack choices.

cheers,Maka

Hi Maka - I think that the wasted spark ignition system can make all sorts of wierd s^%t happen if an injector goes wonky. I'm pretty sure I was reading 1.2 ohms as well when I metered mine as part of troubleshooting (that was a new coilpack too) so I don't know what the story is with the specs.

In short I think dodgy injector causes the spark to not work properly - so the result isn't quite what anyone who's dealt with carby / dizzy ignition would readily pick as being a fuel issue. That's the case with me anyway, I was convinced for a long time that it was either ignition (after all that's what I'd just been bugg ering with) or a BAD air leak - but all the ignition checks - including testing by replacement - came up trumps as did all air leak tests and ultimately even fitting a new manifold gasket. At that point I figured injectors was really the only thing left to try. Online I had been finding descriptions of similar issues indeed being solved by replacing or cleaning the injectors - but for each of those there was another that came down to buggered coil. All adds up to headspin...

All you can do is try those injectors and hope - after the car being buggered for weeks mine's now going absolutely beautifully after replacing the injectors.

Thanks for the prompt reply Greenmachine much appreciated Im old school & yeah it had me stumped until i came across your fine efforts here at fordmods I also replaced the inlet manifold gasket, iac, tested with a known working ecu, checked numerous other things but in the end it had me stumped and i gave up troubleshooting my au for a while, even heard people say its meant to be like that lol! Ive got nothing to lose trying my spare injectors-will check over the weekend and will let you know how i go. Any tips on pulling the injector out? ive never touched the injectors before just dont want to stuff anything up. I'll spin out if all along it was a dirty injector!
Thanks again for detailed advice, i can definatley say i know what you went through in chasing this little gremlin lol!

cheers,Maka

No worries - fingers crossed it works!!

You can change over the injectors fine in situ - ie. without having to even undo the fuel lines - there's enough room and movement to release the injectors once you remove the 4 x 10mm bolts holding the rail feet down onto the manifold.

Relieve pressure in the rail first by unplugging the fuel pump wiring connector in the boot and crank the engine (if it starts then let it run until it stops). Do a few cycles of 5 seconds cranking with 5 seconds rest in between. You'll still get a little bit of spillage but not gallons of it pouring out everywhere.

Hardest part is the fiddlyness of the electrical connector clips and rail cup / socket clips.

Altho I forgot to do it myself, a little squirt of WD40 onto each end of the injectors before you begin can make it all a bit easier - ie. ease any binding the O rings might encounter when ur trying to pull them out of their holes/sockets.

Lube the O Rings with oil or petroleum jelly - and also lube the rail socket / cups and the chamfers of the holes in the manifold. Those O rings are very hard wearing and resilient - so have a good look at them, but you should find they'll all be fine for re-use. If u have new ones then use them of course.

You shouldn't have to remove the whole rail - but I did because there was clearly rust in each injector socket / cup - so I had to pull the whole rail out to clean it all up properly - ie. had to undo the 17mm Fuel Pressure line and take out the 2 x 10mm bolts holding the Pressure Regulator and pop it out of it's socket on the end of the rail - then I was able to withdraw the rail forward under the TB without having to take that off. If you end up having to remove the rail then also removing the TB would clearly make it easier.

Thanks heaps for the comprehensive write up & tips mate! I will for sure have a good crack at it this weekend. Very appreciative of the effort you went to help me out.

cheers,Maka

No worries - and I've just realised / remembered the AU fuel rail won't have the same sort of fuel pressure and regulator / return connections I was describing for the EF.

Instead the AU goes back to an arrangement where the pressure line and return line are both hoses simply pushed over pipes and clamped - from the factory I think with little crimped clamps - ie. so disconnecting the lines is done at the other end where they join the lines to and from the tank - not at the rail end. I'm not sure if the "quick release" fittings on the other ends of those lines - ie. down near passenger's feet - are easily released and reconnected without special tools? The Ellery manual just says release them and reconnect them - so hopefully they're the type with a whitish plastic collar that u just push in to release and then to reconnect you push the fitting over the spiggot and pull the collar back out again which locks it. Otherwise it'd take cutting off those little crimped clamps and replacing them with small tridon clamps.

None of that's relevant of course unless you need for some reason to remove the whole rail.

And ur gonna end up with a sore back and backs of legs

G'day Greenmachine, a sore back/backs of legs is only a small sacrifice for a proper performing falcon - ive had this problem since i bought the au and it goes alright but as you know its got to perform 100% not 98%. im thinking to try not disturb too much when replacing the dodgy injector and to just look and see if theres any rust in the fuel rail.

Ive got a spare fuel rail so if theres any problem there it should be all good! Thinking about this number 1 cylinder, i remember looking at the plug and thinking its running a bit lean - wouldnt a blocked injector cause this ? If it was dodgy ignition supply, the plug wouldve been a bit black from running rich? Can you confirm if my thinking is correct?

After this little realisation (if correct) and with your quality instructions i feel really confident to tackle and fix the problem and that a dirty injector can indeed cause spark degradation on its corresponding number spark plug. Fingers crossed by this arvo the au will have all its herbs back & running like it should lol. Thanks heaps mate!

cheers,Maka

Changed the injector and we have sucess! Will be monitering it over the next couple days but spark now seems more consistent and miss has smoothed out at idle. Big thank you to Greenmachine for all the great advice.

cheers,Maka

Woot!! - awesome - hope that's it - will have fingers crossed for you - and you're welcome

I am looking at the Coil upgrade, which is why I have resurected this thread. I am looking at 3 brands and would like peoples opinions/experiences with these brands, maybe not these particular coils but the brands. No i am not interested in fitting an AUII/III coil.

a) MSD - I know V8 guys who wouldn't piss on MSD if they were on fire, others swear by them.
http://www.summitracing.com/parts/msd-5 ... el/mustang


b) Accel - I do know Wagondad fitted one of these and maybe he can elaborate on his experience.
http://www.summitracing.com/parts/acc-1 ... el/mustang


c) Screamin Demon - the reason this thread began.
http://www.summitracing.com/parts/DUI-31736/


These coils are replacements for V6 Mustangs, 4.0L Explorers and UGGGHHHH V6 Taurus. These come either has the vertical plug as shown or horizontal plug. The coil will be mounted on the Rocker cover where my current coil is mounted, ease of access and lead change etc, have had no issues at all with this postioning. I will need to make up an adaptor mount for the coil as the mounting holes are different. EF/AUI coil sits flat, these coils sit into a mount, no big issue as being mounted on the rocker cover, access is easy . Leads are also no problem, as Auto Pro can get custom leads made up in any length and plug configeration. Leads I had made up for the stock coil set me back $36.00 and took 2 days, new leads are $142.00, bloody AU V8 coil plugs are are killer on the price.

Any sensible opionions/experinces on these coils with be appreciated.

Being able to get leads custom made like that is gold! - great info there - hopefully someone can provide useful info on those brands - you could also pop onto some of the US forums and ask around too - yanks can be a bit strange but are generally harmless enough. I'll be interested how you go as this is where I was actually headed with my project but chickened when info on exactly what the situation is with leads seemed to dry up - so I went with AU3 coil.

As a matter of interest, after I did the head my engine had a very even note / purr - ie. with the typical I6 "lope" conspicuously absent - so much so I was seriously concerned there was something wrong - ie. perhaps leaking or riding valves or something - but in the end I figured it was running so well there couldn't be anything too serious wrong. THEN - fitting the AU3 coil brought back that lope. Very odd.

Paul, MSD stuff, The coil for dizzy setup is notoriously s**t, thats where the bad rep comes from, Just ask EVL 098, the coil pack however that the AU V8's run are a good bit of kit. In saying that, I would confidently be looking at any of those mustang 6 banger coilpacks. as long as you are confident you can get it to work in your setup.

why are you looking to move away from the factory coil pack? I think you have told me before, but my head is a minefield of s**t and I cannot recall.

also, when is DOC making an appearance at Livo again?

Thanks that Dave. I knew that the Dizzy style coil was bad news and also have heard of issues with the MSD Dizzy as well.

As you are aware the EF's run with a 1.0 - 1.1mm plug gap. With the Screamin Demon and the Accel (and I assume with the MSD) you can open the gap to 1.6mm gap due to the better spark (higher voltage). Larger the spark the better the burm. other thing is with boosting you need to reduce the plug gap to stop spark blowout. You should be able to maintain the 1.1mm gap or even a little larger with these coils on a boosted application.

I do know that Wagondad had an Accel coil fitted to his car but his major issues were leads, and coil mount, he mounted the coil in the factory position (stupid place). With my coil being mounted on the Rocker cover it will be much easier. My biggest issue was obtaining the leads in the correct legths with the correct plugs, this in the end was easy, my thanks to Auto Pro Campbelltown who were extremly helpful and went out of their was over the Xmas period to help.

As for Livo, I have been very busy with ny current project which should be installed and running late this month or early Feb. I hope to get down soon, been missing a lot of the s**t that goes on down there .

Last edited by SWC on Sat Jan 05, 2013 8:28 pm, edited 1 time in total.

Yep as you are aware Paul I was burnt bad by MSD s**t.
I had written the product off totally and it took a lot of convincing for me to put the MSD coil packs on our AU's.
Im glad I gave them a second chance. No issues to report of of yet.
The stuff for the dizzy 5.0? Well I now run a crane setup.............................

Will be good to see your cranky face again!