Idle and surging issue.

[kiwikid10]

Hi there,

My AU has started to idle a little rough and not perform as normal.
that is when i accelerated, the car was really sluggish until 3500 RPM then bang took off.

So I booked it in for a service, and noticed that it got worse by the day.
checking the forums last night I decided to try the ECU reset, but no joy.

So during it's service i had the fuel filter replaced and asked for the spark plugs to be checked etc, I remembered the injectors but forgot to mention it to them.

My mechanic said the fuel filter was rotten, I figured that i got a bad batch of fuel, as I had a temporary surge problem but it went away after the next fill. The good blokes at my local ford dealer had done a spectacular effort and only changed 4 of the 8 spark plugs at the 100K service :, (1 bank was platinum 1 bank was off the shelf c**p) so i now have Platinum plugs thanks to my real mechanic.

Problems is it is now idling worse than before and the power loss is really noticable along with the surge, my mechanic ran out of time to diagnose what the problem was today, but before i take it back any suggestions.
i am thinking injectors, note: i only run 98 RON and only from Mobil, Caltex and Shell.

Your help in this issue would be appreciated guys.

[SSD-85]

Really shouldn't be running 98ron unless it's tuned for it, the reason being is that the ignition timing on 98ron differs greatly, along with required engine compression, after continued use it could burn your valves (worst case). i experienced the same issue (only whilst turning it over), went back to 91ron not a drama after that. And Caltex is by far the WORST fuel i've put in a falcon, rough as guts like it's full of water.

But if you don't think it's a fuel issue, then maybe try looking at your throttle body/air intake, could be dirty.

[kiwikid10]

I have a capa flash tuner and was running the 98 tune.

Mainly use Mobil, and the throttle body was cleaned as part of the service.

[ayeyew]

Oxy sensor maybe? TPS? ISC?

I have no idea what those 3 things do, but i remember them always coming up in discussing stalling issues?

[EvilChief]

Originally Posted by WeHaveIgnition

Really shouldn't be running 98ron unless it's tuned for it, the reason being is that the ignition timing on 98ron differs greatly, along with required engine compression, after continued use it could burn your valves (worst case). i experienced the same issue (only whilst turning it over), went back to 91ron not a drama after that. And Caltex is by far the WORST fuel i've put in a falcon, rough as guts like it's full of water.

But if you don't think it's a fuel issue, then maybe try looking at your throttle body/air intake, could be dirty.

WTF comes to mind ... but anyway

if its a 6cyl, 3500rpm is where the BBM manifold opens up secondary runners. when i turbocharged my old falcon is took the butterflys out and it was very dull until it hit 3500, where the butterflys would open up. so i would have a quick squizz if the actuators operates at the threshold.

cheers
mic

[SSD-85]

Originally Posted by EvilChief

WTF comes to mind ... but anyway

Sorry, I'll be sure to just stfu in future.

[EvilChief]

caltex vortex is the worst 98 ron fuel on the market. the ecus are adaptive to learn for new fuels, especially higher ron fuels. the ignition time tables are used as a base figure, however from there the ecu can davance the timing further until the knock sensor detect knock and back it off. that exact progress is called the adaptive learning progress. So either you havent given ur ecu time to learn this very progress or u just got fuel. engine compression would increase the benefits of 98 but not neccessary. burnt valves, havent seen that happen since cars with heads for leaded fuels, these days we have hardened seats and valves.

[kiwikid10]

Problem solved, in the new set of spark plugs one had a hairline crack and was discharging through the block so the car was only running on 7 cylinders at idle, and that also caused the surging.

[Lou Snut]

BF2 fairmont on straight LPG here

Jeeze i've had the erratic idle and surging on cruise control problem for a couple of years now, reading threads like this turned out to be useless, tried the oxygen sensor, changed plugs and coil packs, sometimes it would fix for a day or two then slowly back again.

pulling the battery lead off and reseting the ECU seems to have fixed.

do a search on ECU reset for falcons, there's a little process you go through when you start it again, but now works absolutely fine, and has more power too.

just posting here because when i google the problem, erratic idle and surging, this is where it led me, and , no offence, all advice was useless.

the ECU reset seems to be something people either know about, or dont, so I hope this post can help someone suffering similar issues in the future

[Uncle_Ken]

Check the last post date but advice is always welcome