Engine missing V8 308 VK

[craigvk]

I need some help with this one. Now it's my turn to get some ideas.

The other day whilst turning into a street, the car coughed a bit like it was missing as I was accellerating up the hill.

When the car is in park and idling, every 3-4 revs I can hear the motor missing.

I have checked the spark plugs and the ignition timing is fine. If it was a bad valve then it would be missing every rotation. It's got me stumped.

I first thought I got a bad tank of gas but that can't be right.

Any ideas?

[craigvk]

It's running lpg at the moment. I have checked the mixer and gas flow.

[atrail308]

if its missing at idle as well as accelerating, try your ignition module, its a common problem for them to pack up in the std HEI dizzy...

[burnz]

I need some help with this one. Now it's my turn to get some ideas.

The other day whilst turning into a street, the car coughed a bit like it was missing as I was accellerating up the hill.

When the car is in park and idling, every 3-4 revs I can hear the motor missing.

I have checked the spark plugs and the ignition timing is fine. If it was a bad valve then it would be missing every rotation. It's got me stumped.

I first thought I got a bad tank of gas but that can't be right.

Any ideas?

have another look at night you may see somthing

[craigvk]

have another look at night you may see somthing

What do you mean? Where?

[atrail308]

im guessin he's meaning tracking/arching of ignition...

[craigvk]

if its missing at idle as well as accelerating, try your ignition module, its a common problem for them to pack up in the std HEI dizzy...

Don't those usually if failing pack up completely and refuse to start the motor? Thanks.

[atrail308]

they can sometimes be intermitted, when its on its way out it can show early signs by missing...

[craigvk]

Cool man. Thanks for suggesting it. I have a mate that has a couple of spare second hand ones that I will try out next week. I think they are $55 each new, so I aren't going to buy one unless I know it's that.

Any other suggestions before I replace the module?

[atrail308]

it sounds like its igntion if it does it when you're idling AND accelerating, so just make sure evertything is up to scratch, throw a multimeter on your leads to have a quick check for resistance, also check out your rotor, cap and coil contact points... After all of those, if still being ignition at fault, it could only be your module left...
good luck man, let us know how you go...

[craigvk]

Yeah, the leads are Top Guns and are virtually new, only bought 4 months ago and I have only driven about 2000 K's. The rotor was replaced 10 months ago. The coil contacts are fine. I suppose if they wern't, nothing would work.
I haven't looked at the cap, but if it was cracked, it would probably be doing more than a bit of missing. More like backfiring and running like a total barge.

Thanks mate.

[atrail308]

true that is, i'd still say it does sound like your module... give a second hand one a go, then you'll know for sure, but hey, i still may be wrong...

[craigvk]

I hope you're right.

[Cane_It]

check the coil.

[craigvk]

I'm sure the coil is ok. I am getting this module Friday and he is also lending me his timing gun. I have to take the dizzy out to get the module off. Hopefully I won't run into any other problems.
Today the car was running like a barge. The engine missing is getting much worse.

[atrail308]

you can do the module without taking out the dizzy, just undo the 2 screws at the top, then take off the metal cap and unplug the 4 plugs in the module, just make sure you dont get the wires mixed up...

[craigvk]

The module is at the firewall side and I can't get to it.

[atrail308]

you should be able to, mine's in the same spot... i did it with the dizzy still in so i didnt have to play with the initial timing of the dizzy...

[atrail308]

it makes it a lot easier to have the small cap conversion, a lot more room to move...

[craigvk]

So I should take off the cap extension and then I should be able to get to it without taking it out? If so, great.

Do the earlier models have a small cap without the extra housing? I thought the purpose of the adaptor and larger cap was to stop cross sparking?

Cheers.

[atrail308]

yeah, if you take off both parts of your standard dizzy cap, aswell as the rotor button, you'll be able to get to the module without taking out your dizzy...
as for the small cap conversion, the HEI ford v8's, such as the XE-XF's used the same dizzy but a different rotor button and a small cap, the same as the old red V8's, if your ignition system is up to scratch, there would be no reason for the tracking/arching...

[craigvk]

I remember now seeing my mates 253 red motor having the standard cap. Also my cousin's Cleveland XB's & XC's all have the standard small caps. I have only seen the large caps in later model commos.

[atrail308]

yeah, but just remember the rotor from the old red V8 wont fit cos they were points dizzies, you'll need the rotor from the XE-XF falcoon...

[craigvk]

Oh yeah. I know the old reds had a points dizzy, why is it with the electronic ones require the dizzy to be spaced?

[atrail308]

they original had the idea that it would start cross tracking due to the higher output of spark, so they used the larger cap so this problem would not occur... but, if an ignition system is running at the right output, the right timing, a good contact in the right spots and minimal resistance, there is no reason for it to cross track or arch out...