HI guys. i think i got a problem or could be a problem, anyway when i'm in enclosed spaces like carparks or my garage and i'm sitting inside my car and push the accelerator, it makes a tapping sound from the engine, almost makes it sound like a diesel and seems to be very loud. Is this normal? cause i can only hear it faintly when in open spaces, and also it doesn't make much noise when its idling, is it got something to do with the lifters or something?, cause thats what someone told me but i have no idea.
any info would be great thanks.

yes sounds like your lifters are stuffed
u need a seal kit and that will give u new seals to put on the lifters,
u can try some lifter free first.

also u may have a exhaust leak at the manifold as this can sound liek the lifters

could be lifters or requre shimming???
Could also be timming chain warn as well as guides...
Repalce if over 200,000 lmrs...
change oil often helps...

I changed my oil regularly myself and the car is got 170,000km on it, is it going to be expensive to fix if it was the lifters? btw this is a au I6.
and would this be a DIY , i'm ok with tools but not great.
thanks for the replies.

one more question. is this problem serious, like if i don't fix it, the engine might blow up or something? thanks again.

Lifter noise is usually worse when idling, as there is less oil being pumped up.
This could be, as Frank said a exhaust manifold leak.

You need to stick you head under the bonnet and have a real good listen to where the noise is coming from, then get back to us.

I agree with with madmax... If the Au's are like the E-series they have a 2 piece exhaust manifold and a gasket between the two halves. In my experience I have seen about 5 or 6 E-series blow that gasket out and they make a ticking noises only under throttle {load} and are perfectly quiet at idle. The gasket is about 10 dollars and because the manifold has to be taken off to do the job it should take you about an hour. Note: if the nuts that hold the two manifold halves are tight to get off then use WD40 or eqivelent and leave for a couple of hours to penitrate and they should have freed up. If you keep turning them when they are tight then the will most certinally snap the stud off and thats when you start throwing tools around the shed.

One way to see if it is you lifters is to sit in neutral and bring the revs up to about 2000 rpm and if the noise gets louder then it will be your lifters. Replacing the lifters is nothing hard. I would replace the rocker cover gasket at the same time. Will add about 15 dollars to the job and will avoid oil leaks when you put the rocker cover back on. The lifters will set you back about 200 dollars for an exchange set. Maby a little more or a little less. Hope this helps.

if it is the lifters u may not have to replace them a re seal kit is all that is usally needed

and the lifters are avout $40+ each.. wheila seal kit is liek $15

Well on another similar Thread to this exact topic See:
http://www.fordmods.com/forums/viewtopic.php?t=8474
someone pointed out they are actually Not called lifters But are actually called "Lash Adjusters" on EA FAlcons Onwards

I'd try the Lifter Free from Nulon (I think) first, just incase it works - as this is the cheapest option.
The retainer clips (which are the seals that Franks talking about) for the Hydrolic Lash Adjusters are less than $25.00 for 12.
A replacement Hydrolic Lash Adjuster is about $35.00 - there not a repairable item, there designed to be replaced if they break. There's 12 all up, so you'd be best of find which one, or ones are buggered, as it'd cost a fair whack to replace all 12.