just got an NL fairlane 238000ks pics coming soon, any way ive noticed that when idleing and even cruising on lower revs ie under 1500 the idle drops every 2-3-4-5 seconds for a split second and rocks the car, i can feel it, i can see it on the rpm meter and sort of hear it, it seems to happen more when the fuel tank drops to 1/3rd i dont know if its relevant also happens in drive and park and if the AC is on or off.

is there any common problem that causes this? what should i check and how to diagnose this?

thanks in advance, i just got this car and it cruises awesome but this seems to have got worse since i got it on thursday.

please help.
a mate reckons its electrical, not powering properly, take it to someone who'll hook it to the computer he says.
power being the issue sort of makes sense because when the revs drop it sounds for a fraction of a second like its about to stall the it picks up, then it almost stalls, and if im at the lights and when it drops if i take off at the same time, it stumbles then goes.

dizzy/leads/plugs.

that's what i was thinking after reading some stuff elsewhere, any tips for checking these things? before i go pull my new car apart and cant go anywhere if i stuff it

it wasnt plugs i changed that first as it is the easiest, the problem got so bad the car wouldnt start at all, so next morning i got leads and distributor cap off and found where the coil lead was attached to the dizzy, was covered with carbon and corroded, also the connection with another lead was corroded and the cap was in generally poor state. i started to wire brush it but thought bugger it ill go find out how much is a new one, thankfully i stalled in a shopping centre car park 2 mins walk from 2 auto outlets, so i was able to get a bosch dizzy cap for $25 and champion leads for $70 (dunno if thats a good price) and had my car going in an hour, certainly a worthwhile experience and im wrapped that thats all there was to it.

How's the idle now that you've replaced the dizzycap and leads?

also, make sure that the inlet manifold bolts are nice and tight, had the same kind of thing on a AU3 ute at work, replaced coil packs, leads, plugs, ISC, but it kept on going back to missing heaps ...

then i though! (no coment about blondes) LOL that maybe the intake mainfold was lose, so i had a go at it, and some of the bolts where only hand tight ....

I've seen this on a few falcons, mainly because the heat from the cly head, makes the gasket shink ..

I'd check that out ....

Laticia.

idle seems fine now, when i can im gonna replace fuel filter for good measure and down the track try out that injector cleaner i read about here metho and acetone or whatever