Please help, before i kill my car!!!

amiers · 26-10-2009, 09:52 PM

A little back ground first. my car is an AU2 5L dual fuel Fairlane. i have owned the car for 4 years and 100.000 k's. when i bought it i did the plugs/leads ect it has never missed a beat on petrol or gas in that time.

fast forward to 3 weeks ago, lpg converter failed. booked it in for next week. gas guy asked to make sure car was running right on petrol. so i thought it was about time for some plugs and stuff. asked what plugs he thought were best, NGK BPR6EFS was the answer. i took out my plugs, they were just about stuffed, they were BPR5EFS-13. and now it all went south!!!!!! Put in the new plugs, car wouldnt idle, drove fine but wouldnt idle. put a post in the lpg forum and general thought was 0.8 gap was too small, rang gas guy, he said try 1mm gap. did that idle better but still lower than should be, reset ecu, now idle rising and falling. rang gas guy, go to 1.1 gap. at this point i checked the gap on my old plugs allowing for wear, about 1.1

so set the gap at 1.1 idle better but still too low but steady, took it for drive idle now rising and falling again. so one minute i have a car that runs smooth as, i change the plugs and it does this!!!!! so is it the lower heat range,6, and the plugs are fouling at idle? or is it the gap? With the BPR5EFS-13 the car ran perfecty on gas and petrol. i checked the ics it seems ok but when i unplugged it nothing happened? could it have all of a sudden gone dead? before the new plugs went in the idle always ajusted itself when the air came on or i put it drive now nothing. i have checked all the vacum lines and anything else i might have bumped

please any idea's

GK · 26-10-2009, 10:02 PM

The new plugs are 1 heat range colder than the ones that were in there. Colder range plugs run better for gas, but not as good for petrol.

Go get the plugs like you had in there before and regap them to 0.8-0.9. That will give you the best of both worlds.

GK

amiers · 26-10-2009, 10:12 PM

the thing that gets me is that the more i gap the plugs the better it idles and why isnt the idle ajusting itself like it did ?

bodes-sh · 26-10-2009, 10:47 PM

did you run through the relearn procedure when you reset the ecu? it should fix itself, although it may take a bit of driving to sort itself out

amiers · 26-10-2009, 10:53 PM

yes every time i reset the plugs

bodes-sh · 26-10-2009, 10:57 PM

how much have you driven it since you did the last reset? it might be worth cleaning out the isc as well just to make sure it is nice and clean

amiers · 26-10-2009, 11:08 PM

drove it for about 20k's after setting the gap at 1.1 i might go back to the right heat range, 5, and set the gap at 1.1 or 1.2 and see how it goes

amiers · 28-10-2009, 01:40 PM

ok, put the recommended plugs i the car BPR5ESF-13 and cleaned the ICS. at first it still idled too low, then for no reason it started to run as it always has. idle was perfect and drove like a dream, about 5k's into the drive it developed a miss got it home and the idle was back to low and surging. let it sit for a while running and it started to run ok again, gave it a few revs and then It went back to bad idle. pushed and prodded every connection in the engine bay but found nothing. however i did find the plastic line in the pic. it was under the heater tap, cannot see where it goes or if it goes anywhere.

im starting to think maybe a lead is playing up? the only thing i have done is put in the plugs, so could new plugs stuff up a spark lead? coil pack? im running out of idea's

P.S dont know if this could have anything to do with it. had to get a battery in a hurry and bought just a standard one it has been fine but in the last week it seems to go flat in about 2 days, when i drive the car it seems to charge but i wonder if the alternator is going? would this affect the car on idle?

Erich · 28-10-2009, 02:14 PM

Battery shouldnt go flat that quick - get the charging system checked - should be charging about 13.7 to 14.1 volts

If the battery is NOT recommended for the car - yes. Cars these day need a suitable battery to run all the electronics, expects certain voltages at certain spots. The AutoElec can advise on that also

amiers · 28-10-2009, 02:49 PM

thanks ERICH, it is to suit a Ford v8 but not heavy duty. and i suppose up til now the car has run fine. but i will check it

Erich · 28-10-2009, 03:16 PM

I see she is a Fairlane as well so she would love to suck up all that voltage ;)

Cars these days are suseptable to voltage drops - not saying its a certain but if the battery was fully charged, it may have been ok for a bit then there may be a fault with the alternator not keeping up with the discharge. Auto electrician will be your friend here me thinks

FordACE · 28-10-2009, 03:46 PM

that little vacuum hose is probably the cuase of your problems. it sticks underneath a vacuum switch, I think it generally controlls the heater core in the car. could be wrong.

AMB · 28-10-2009, 05:23 PM

The battery is really only there to start the car. Once its running, the alternator does all the work, supplying all the power. Heaps of power is needed, thats why the alternators these days are something like 150 Amp or more.

The Monty · 28-10-2009, 08:13 PM

Id say your whole problem is your battery, if its going flat. Its not getting enough time to let your ECU to relearn everything after a reset. You need at least 100km of normal driving to do this, and then, if it goes flat when you stop it, and it gets jumpstarted, youll need to go for another 100km.
Get a new battery, let it learn, and then tell us how it goes.

RG · 28-10-2009, 08:50 PM

That little hose is definitely a vacuum hose and will affect idle quality if disconnected.

Sounds to me like you have either a dodgy lead or more likely a stuffed coil pack. How many k's she done and have you ever replaced the coil packs & leads?

scrivens · 28-10-2009, 10:33 PM

Had one of these a while back, petrol only, but similar problem. Turned out to be poor earthing. Wouldn't idle smoothly, lights flickered a tad at idle and so on. Everything checked out OK in the system (battery, alternator, plugs, coils etc) but a thread here yonks back put me on the right direction. Start with the main body earth and go from there. That line is a vacuum hose as others have pointed out and it will cause rough idling if not connected.

amiers · 29-10-2009, 12:02 AM

thanks guys, update till now. drove car for about 50k's tonight. still idle's at about 400 rpm. miss is gone, but it seems to be surging under load. the battery now seems to have full charge. i think the problem there is i dont drive the car much i.e maybe once every 10 days and since this drama started last week it has been wound over a lot and not driven.

i have looked everywhere for where that hose goes and cant find a place.

the thing that still gets me is until i changed the plugs the car ran faultless.

i pulled each lead off one at a time and there was a drop in the motor, so i can assume there is spark to each plug. as i said before there was 10 min today when it ran perfect, then it went back i didnt touch anything it just ran perfect

as for the age of the leads, coilpack and o2's i have no idea. i have done 40,000 since i bought and i havent done them. HOWEVER as i said until i changed the plugs it ran so well you wouldnt even know it was running, so what changed? it also behaves differently every time i drive it

FordFalconBF · 29-10-2009, 12:58 AM

I had a similar problem in My AU Fairlane.. turned out the coil pack was stuffed.. even changed over the leads (needed doing anyway) and the o2 sensor... Just bite the bullet and take is somewhere and get the to diagnose to fix it..