XR9UTE, thanks for the suggestions and I do realise that there's been a lot of good information given in the forum, I thank everyone again that has written in...it's pry saving me about $70/hr that Ford would charge to diagnose the problem... I have certainly checked out most of whats been mentioned but I thought it'd be handy to list what I've done...so here goes: NB: the car had the problem before all these things were done
- new plugs
- new leads
- new fuel filter
- clean K&N from previous car fitted
- cleaned MAF sensor
- checked intake for leaks
- cleaned dizzy cap and rotor (quite a lot of arcing residue present -apparently normal according to Ford)

- ran ECU diagnostics, none found
- backprobed most critical sensors (intake air, coolant, HEGO sensors, both TPS's etc:)

- backprobed the ECU to double check...HEGO's are switching and MAF values as posted previously

- replaced MAF with secondhand unit (made no difference at all)
- ran car without MAF connected and this seemed to make it run a whole lot better although down on power and a bit funky at times...no miss or black smoke however (indicating a timing issue?)

- mucked about with timing (no timing light so just slight adustments advancing and retarding...no difference except higher/lower idle)

- checked EGR valve out, seems all good, disconnected coolant lines and ran just for good measure (thinking maybe coolant escaping to intake)

and thats about all at this stage...and the problem persists !!!
Things I have still to do:
- check fuel pressure in fuel rails
- recheck intake for any leaks - DONE, ALL OK
- check old spark plugs for different burns (thanks XR9UTE)
- post a sound file to let you guys hear whats going on... - DONE, VIDS
- have Ford check it out (last resort, most expensive...bugger)

Last edited by Windza on Wed Mar 15, 2006 8:25 am, edited 1 time in total.

Guys, I have posted some clips of the car running with and without the MAF connected...
If anyone's interested...

www.dropshots.com/windza82

The first one is with the MAF connected, notice the smoke...the second is without the MAF...much nicer running...

Watched the clips.
Does it ping under load?

I'm not an expert but all I can come up with is either the MAF, an O2 sensor problem or one of your new plugs or leads is faulty and breaks down under load?
( I have had the unfortunate experience where a brand new plug turned out to be faulty - it's not impossible )

V interesting..

Does this mean that your maf is buggered or that its meant to run with that smoke? (i would think the 2nd to be pretty stupid tho)

Whats the verdict guys?

sorry dbl post.

Vic and Daniel,
This is what I've had to conclude
- definitely not meant to run like it does...
- very unlikely to be the plug leads or plugs as the problem persisted before and after replacing the old ones...
- unlikely to be the MAF as I have tried one I bought from "offyaguts" (although it is secondhand and may have also failed...)
- not sure about 02 sensors...they are switching within the typical values however and seem to work ok when the MAF is disconnected
(not sure if ECU goes to "open" loop without the MAF though, if it does it could still mean 02's may be the prob)

I am thinking maybe something in the timing circuit (coil, PIP etc:) as disconnecting the MAF defaults the timing to base and this may be why it runs better without the MAF...just a theory anyway...but I really don't know how to check much in the way of the timing circuit...unless someone can elighten me...

Oh yeah...Vic, I haven't noticed it pinging at all...

There is MAF failure mode map that the EEC reverts too when MAF signal is lost. It does go open loop at this time.

Pete.

Alright then, so an O2 sensors could still be causing the issue...I might get two anyways and try them...can't hurt and still pry cheaper than having Ford diagnose it...

Have you checked your EEC TPS voltage at closed throttle?
What is it?
Is the change in voltage smooth and proportional as you open the throttle slowly?

XR9, this was one of the first things I did, can't remember the voltages now but was definitely up to spec against the Repco Auto-tech CD I have, was smooth and proportional as well, I have also swapped the plugs on the two TPS's and found no difference. Adjusted them also without screw in place and couldn't make the car run better so I'm fairly confident they're ok...back to the O2's, I can get two off ebay for about $110 with shipping, is this a reasonable price, anyone know of cheaper ?

Alright, well latest update is that I bought two O2 sensors, fitted them, ran and NO FREAKIN' DIFFERENCE....what tha !!!! About the only thing left now is something in the timing circuit (dizzy, coil etc:) or the computer itself...guess I have to leave it with Ford...bugger

No one has a computer they want to lend... Well hey, it was worth a try

Well...still no progress to report and no change in the car's behaviour...the car is finally booked in at the Ford dealership next week although from what the tech said they aren't real hopeful either as they probably can't do much more either..hmmm. But all this leads me to ask a question that I should've asked first. Does anyone elses V8 from the same year show similar symptoms ? A few people have now said that maybe it is normal behaviour... and that the computer cannot increase fuel flow fast enough and the engine leans out for a split second... I really am just stabbing the throttle to full open and then releasing when it gives the miss from idle... ARGHHH, sorry to be an annoying bore but dang this is frustrating !!!!

Why is it that any posts about Ford workshop technicians almost always indicate that they are idiots who couldn't identify a spanner from can of Coke? I think I'm more likely to learn the answer for a mechanical / electrical problem from an independent mechanic than I am from an authorised tech.

Well I talked to the Ford Tech today before handing the car over ( I had made a booking)... I asked whether or not they could gain any more info from the computer than what I had already gained through the diagnostics...short answer...No. He couldn't suggest anything more toward rectifying the situation than what I've already done. So thats it...I left without them looking at it...simply no point...now I drive a car that no one can fix...sheesh !!!