I done fuel filter as well

Do you have a spare ECU?

It could be a dodgey ECU.

Swap it over and try that.

Bought a second hand one and it did exactly the same. I hardly think I would end up buying one that has the exact same problem if it was the ecu.

I have a Ford Falcon EF 96 thats been having EXACTLY the same problem as what you have stated in this post.

I recently replaced the head with a brand new one, new head gasket, intake, exhaust, water, thermostat gaskets all new, replaced harmonic balancer, brand new injectors, fuel pressure regulator, coil pack, MAP sensor, leads, plugs, ISC motor, ALL filters, CAM angle sensor and crank angle sensor...with no luck on any improvement to idle or accelration under load.

It happens intermitently, but for most of the time.

The car idle fluctuates under load, at idle and almost sounds as if the engine cuts out momentarily every 15-20secs.

When I reset the ECU, it was fine for about 30 mins, but then started doing the same thing again.

I wouldnt have a clue as to whats causing it, so was wondering if you ever resolved your problem???

Any help would be greatly appreciated, as its also doing my head in.

Hi mate. U did pretty much what I have done. I have had no luck. An auto elect told me I need a new idle motor and sensor and refurbish Ecu. I bought a new idle motor off ebay for $95. They r normally $180 odd. He told me if I put a second hand non refurbish ecu I might have to try a few until I find a new one. So I think if I have tried two different ecu's with the same problem its not the ecu. And now not the idle motor cause it never helped. The sparky I think knows what it is and is a quick fix trying to sting me for $600 to replace the idle motor and ecu. My car now rev's as its changing from second to first and jolts forward. So I put the old ecu back in. And what do u know. It now is doing the same thing. The ecu means nothing its got nothing to do with it. Its a censor somewhere that we don't know about. I haven't changed the oxygen censor. I took mine out and ran it without it. Was no change. Wouldn't you think if I took it out it would run like s**t? It already was and didn't get worse maybe its already not working that's why there is no change. But as for now. Without changing the co censor. Its still the same.

Hi mate. U did pretty much what I have done. I have had no luck. An auto elect told me I need a new idle motor and sensor and refurbish Ecu. I bought a new idle motor off ebay for $95. They r normally $180 odd. He told me if I put a second hand non refurbish ecu I might have to try a few until I find a new one. So I think if I have tried two different ecu's with the same problem its not the ecu. And now not the idle motor cause it never helped. The sparky I think knows what it is and is a quick fix trying to sting me for $600 to replace the idle motor and ecu. My car now rev's as its changing from second to first and jolts forward. So I put the old ecu back in. And what do u know. It now is doing the same thing. The ecu means nothing its got nothing to do with it. Its a censor somewhere that we don't know about. I haven't changed the oxygen censor. I took mine out and ran it without it. Was no change. Wouldn't you think if I took it out it would run like s**t? It already was and didn't get worse maybe its already not working that's why there is no change. But as for now. Without changing the co censor. Its still the same.

Hey there mate,

It seems a mystery as to what is causing the missfire, but after eliminating all posibilities of either bad ignition or air/intake or vacuum leaks, it very well points to the fuel delivery system.

I have read elsewhere that possible culprits to this problem stem from the fuel return line, a tired fuel pump and or fuel lines. Someone even went as far to mention that a dodgey fuel cap may not provide adequate ventilation via the breather hole into the fuel tank and may cause incorrect pressures within the tank to affect the fuel flow in some way???....yeah i know, getting desperate here..

Anyway, im certain that it is definitely somewhere within the fuel delivery system. I will take apart and inspect all vital components of the fuel system and def get back to this post with my results.

Cheers:)

Definately sounds like a sensor issue, not mechanical. The oxy sensor doesnt operate while the vehicle is cold, so this shouldnt be a problem, hows the fuel economy? Has the alternator output been checked?

Fuel pump or fuel lines? Test your pump for correct pressure at the tank and at the engine bay

I get 650-700 ks to a tank city driving. 800 ks highway. Its been excatly the same for 5 years. Never changed. I drove with no fuel cap was same. New fuel filter. If it was fuel pump or pressure after 5 years wouldn't it get worse? There are no leaks anywhere. Even air leaks that I could find. A few times at idle maybe 6 over the 5 years it just died. But started straight away again. ?

Has it had a scan tool put on it by any chance? My old el had some weird idle issues, would idle hunt and idle high and turned out to be a power steering pressure switch issue. Only way i found out was it was checked with a scan tool.
This is a strange problem though..

Hey guys,

After replacing all the bits and pieces on my 96' EF similarly to what topsy99 on this forum has replaced too, I had just recently (last week) replaced the head gasket alongside with a brand new head. Everything had been tightened and torqued down to spec, including mainfolds and new water pump. However, I had ONE long skinny bolt left over, which i couldnt figure out where its location was. Left the bolt out and drove for a week.
Upon discovering a heap of fresh oil on the carport floor (seems to have been leaking from the front of the engine) I popped the bonnet and discovered oil all over the water pump, on the serpentine belt and on the cross member.

I started the engine, idle was fine....until i spotted oil leaking from the bottom hole where the long skinny bolt was meant to be. There are 3 bolts that hold the power steering pump, the bottom one being the long skinny one where there is a slow constant drip finds its way into the alternator.

I suspect that if the alternator isnt outputting a decent constant voltage, the ECU may be getting a surging signal which interupts its calculations and interferes with its output signal to electronics governing the engine electrical management system.

It only takes a minor amount of voltage surge to stuff up the thousands of calculations these micro processors do concerning the EECV system....just like home PC's hate fluctuaing AC power!!

Besides, dont all these EF's have written on the side of the door rubber 'Computer Torque Control'

As Macca2042 suggested, CHECK the voltage output by connecting a multimeter set on VOLTS (12v) to the positive and negative terminals and observe the readings in real-time when the engine idle fluctuates. If the voltage picks up and drops whilst idle is erratic, then this may be your culprit.

Topsy99, you didnt mention anything about your charging system within the previous posts. Check the alternator mate, also voltages to the ICS and TPS to see if they fluctaute during the erratic idle when engine is running.

I will be looking to replace it with a known working one including a new battery shortly so will update this post once done.

I didnt check my fuel system, as I honestly think all is ok in terms of fuel pressure and fuel pump function.

Good luck!!

Last edited by richardheil78 on Sat Aug 17, 2013 11:28 pm, edited 1 time in total.

That's gold. My power steering has been dripping so slightly on the alternator from the high pressure hose. Like all fords. That's gotta be it. It makes sense. Imgonna get it checked and see his I go. Cheats mate. Ill keep u posted on how that goes.

Hehe, Ive also got a bit of tranny fluid leaking onto the alternator too, like all Fords as you said, but with all the extra oil that found its way onto the alternator I suspect that thats gotta be it.

Around a year ago when my car was dying slowly, where it intermittently cut out completely, then started again (whilst driving) including my headlights and dash doing weird sh**t, the alternator was to blame!!!

Good luck with it and ill post up my results too.

Cheers!!

Last edited by richardheil78 on Sat Aug 17, 2013 11:33 pm, edited 1 time in total.

I think u nailed it with that. Bloody fords. The money and time I spent. Could have been saved grrrr lol