304 miss cold start, revs jump on tacho

[calais_cruzin]

Hey ppl

VS 304, past few weeks needed to warm up before driving.

Tacho jumps around when its missing. Would calm down once temp at around 45-50deg mark.

Dizzy 8-9months old

Plugs just done no change

Any ideas?

Not sure if should bite bullet n do leads too, or if there is a sign its coil or ign module

 

[EYY]

Mine does the same, apparently it's a sign of a dying module.

 

[vr304]

Probably want to replace that ignition module sooner rather than later coz it will just die on u and the car won't start, it happened to me in my old 5 litre lol

 

[calais_cruzin]

It was missin bad on way home yesterday arv. This morn first time started n idle trouble free. Couple miss on trip.

Always runs fine when need it to play up.

Doesn't feel like it's just a single cylinder other times it does. Like its a constant miss then goes all over the place.

Say I'm doin 2k rpm tacho would jump around n jump up around 3-3.5k mark.

Would play up for 5-10min then come good for around same time.

 

[calais_cruzin]

So picked up another module last night, goin to grab a coil today for the sake of it.

Anyone know an easy way to get to the nuts holding module down.

Quick look think need to get inside the guard lining to get to the nuts, is there a trick to getting the plastic rivets off without breaking?


Did find another thread with all the exact symptoms as mine, module fixed it.

 

[BlackVXGTS]

..........Anyone know an easy way to get to the nuts holding module down..............

You don't need to take the guard lining off. If you turn the wheel to the left hand lock, you can put your hand in and hold the nut with one spanner in your left hand while loosening the bolt on the module with a spanner in your right hand. Ditto for the other nut/bolt. When you have turned the wheel to lock you can shine a torch inside the guard and see the two nuts in question. Quite simple.

However, my understanding is that tachometer fluctuations are more likely to be the coil.

 

[calais_cruzin]

Sweet. Well I got a new coil too anyway. Figured dizzy done. Another module new coil n plugs. Leads are top gun 10mm still look fairly new. Pre much covered everything then

Thanks for everyone input.

 

[calais_cruzin]

So all changed but still there. Wondering if may be issue with new dizzy that got thrown on last year.

Idles sweet now. Seems to miss after 3500 few times as it winds out.

 

[VS 5.0]

Have you checked the inside of the dizzy cap and rotor button for any damage / signs of arcing ?

 

[calais_cruzin]

I havnt checked inside dizzy. It's not too old. It's a Rae diz. I've got my old Bosch here. Was goin to see how hard to swap rotor n cap as Bosch still has good points it's Hall effect was dead. It's such a pita