XR8 series 3 issues

[Sox]

Ok gents, we have a problem.

The new machine, discussed here -
http://www.fordforums.com.au/showthr...8&page=1&pp=20
is having problems.

There are several issues, pinging, rough idle, and rough transition from no throttle to part throttle.
I suspect they are related and once the problem is found, all 3 issues will vanish.

I have so far replaced with new items -
Plugs
Leads
Fuel filter

No change.

I have swapped over with from my P250 -
O2 sensors
TPS
IAT
PCV

No change.

I have measured and determined they are ok -
Crankshaft sensor
Coil pack

The issues in detail are -
Detonation above 3000rpm under heavy WOT with 95 and 98 fuel.
Very rough idle when cold to the point of almost stalling. When hot it imprives, however is still not right.
When cruising, the transition from idle to part throttle (and vice versa) is not smooth.

The most interesting thing which happened was when I swapped the MAF, it was cured, temporarily.
Next day, the idle was still good, however it began to ping it's nuts off again.

The problems also followed the MAF, in that the P250 had issues. However the pinging didn't, so perhaps the pinging is something else.

I'm stumped at the moment. Any ideas?

[needaXYGT]

carbon build up on the piston heads?

[GK]

Could a cruddy fuel pump/sock be contributing to this?

GK

[Sox]

Originally Posted by needaXYGT

carbon build up on the piston heads?

Sounds very plausible, and I guess a stuffed MAF could cause it.

[Sox]

Originally Posted by GK

Could a cruddy fuel pump/sock be contributing to this?

GK

Dunno, the pinging indicates a possible lean mix, however not sure why the MAF would help the idle.

[Stav]

You have an intermitent air leak...dirty injectors..dying fuel pump..dirty fuel filter?Or...faulty fuel pressure regulator. Check fuel flow first. I use a 2 litre coke bottle and time it for one minute and check it against specs.

[Sox]

Originally Posted by Stav

You have an intermitent air leak...dirty injectors..dying fuel pump..dirty fuel filter?Or...faulty fuel pressure regulator. Check fuel flow first. I use a 2 litre coke bottle and time it for one minute and check it against specs.

Vacuum is good, so no air leaks.
Injectors, possible.
Dying pump, possible though doubtful as it won't ping when the weather is cool.
Changed fuel filter.
Fuel reg, possible, but unlikely.

Today I had a good look in the manifold through the butterfly on the TB, there is a fair amount of oil on the walls.
The oil level is also high, about 20mm over the full mark.
I also raised the PCV as someone else mentioned this in a searched thread.

Will drain some oil tomorrow, attempt to clean the inside of the manifold and see what happens.

[Stav]

Hmm.Try a battery reset.Reset the computer too.Before you get into the harder areas.

[urbancowboy]

Battery reset? What would this do?

My AU2 XR8 is sometimes a little rough on 0% throttle take offs (its manual) when its stone cold and at other times fine, i figure that there's gunk in the inlet etc. I run a bottle of Ford fuel injector cleaner through every 4 or so full tanks of fuel but i'm thinking that a carbon cleaner might help it out too.

Sox. have you run a bottle of anything through the fuel to clean it that way? have you cleaned your inlet system at all yet? Did it help if you did?

[Bolly]

Hmmm see what happens when you remove some of that over filled sump oil..Being too full can cause a number of problems..high pressures in the crank case causing oil leaks, oil building up in the inlet manifold, idle control sol. etc etc

[CRAIGAU3220]

Yeah Sox, Have you fixed it or burnt it?

[5L]

mine had the same problem,

i got mine retuned, but sometimes it re-learns and starts playing up around 1900rpm getting a miss fire is what it feels like.

a re-flash fixes this though.

[Sox]

Ok, have replaced the MAF with one from a wrecker and idle is back to normal.
Starts well, idles well, accelerates fine up to 3000rpm WOT, above that, we still have detonation.

Won't be able to try much this week as I have work commitments getting in the way.

I might try a bottle of injector cleaner as it's cheap and quick.
I did try some carbon clean and there was no change.
The inlet manifold still looks oily though, so I may rip it off after the weekend and clean.

The oil has been drained, twas 2L over full! May need time to rid itself of the oil in manifold.

Would be easier to burn it at the moment.

Still things to do.

Keep the suggestions rolling in.

[Windsor220]

Make sure spark plugs are correct.
Check EGR is ok.
Engine temp.

[cedric]

my 220 pinks with normal unleaded and some brands of premium. what about some octane booster a see if that fixes it

[Sox]

I replaced plugs with - NGK BPR5EFS-13 - which plenty here raved about.
EGR? On AU's?
Engine temp is good.

[Sox]

Originally Posted by cedric

my 220 pinks with normal unleaded and some brands of premium. what about some octane booster a see if that fixes it

Even if it did fix it, octane booster would just be a band-aid fix for a more serious problem.
They should and do run on 95 fuel, my P250 does just fine.

It has an issue somewhere.

[Windsor220]

Originally Posted by Sox

EGR? On AU's?

Forgot AUs got rid of it. Was thinking the older ones.

[madmelon]

I do apologise for the thread mine but I seem to be having a similar detonation problem as was described here. I'm wondering if this ever got resolved...

I've got AUIII XR8 and without octane booster, the detonation from ~3000 onwards is severe. I've only used 98 octane in it for the last year, except once the other day when I could only get 95 and added booster. I've changed plugs (6 heat range, not 5 in an attempt to get rid of detonation), leads, fuel filter, checked fuel pump & sock (has a Walbro which I installed), ignition coils, TB cleaned, oil at correct level, cleaned MAF.

It has a custom airbox/filter/pipe/MAF adaptor made by me but had the detonation problem before and after installation.

Any suggestions? I need this fixed ASAP as I want to go to a track day on 29th of April...

[Sox]

I never actually fixed the problem as such, because I just used 98 fuel.

The car is now sold and I purchased another one, of which it also has had some pinging problems with 95 fuel, though not all.
98 is always good.

I feel they are borderline with 95 fuel, and different brands work better than others.

[cedric]

mine still pings with 98

[b2tf]

Mine have always been run on 95 and never had any pinging.

[madmelon]

Yeah well I'm unlucky because this is on 98 and I've never heard pinging so bad. It's booked in for service on Tuesday at Ford but I'm not expecting them to find anything- last time a misfire due to cracked spark plug was diagnosed as a slipping clutch...

[Donny]

Mine pings a bit under heavy load on WOT with 98, but only pretty heavy load and up over 3500rpm..

[mik]

just thinking out of the box here, but i get a bit of pinging in my vct from time to time,
when i fuel up at certain servo`s, it`s been mentioned in the past the odd servo not having the fuel in the tanks that is listed on the bowser,
perhaps try filling up from a different servo, the first time i heard the pinging i was on the other side of town and very low on fuel and just put fuel in from a little independant unknown servo,
now it was quite obvious the car was running grouse before i entered the servo , and only a very short time later after it got a gut full of this servo`juice it was pinging it`s guts out as soon as i put the boot into it, a couple of days later i diluted the the crappy fuel with the good stuff from my local.......pinging all gone.

[Day-mow]

Good advise!

[5.0 ED]

Fuel pump, replace the fuel pump, they lose there ability to keep enough pressure up to the engine, out of all AU's v8's i've come across 50% of them have a faulty fuel pump.

You can check the fuel pump by simply disconnecting the fuel return line, if its not flowing out of the rail then its faulty and not supplying enough pressure to even open the regulator, however if it is flowing it doesn't mean its not faulty, it just means that it does have enough pressure to open it at "fuel requirement" at the time.

Best way of course is to check the fuel pressure with a gauge into the shroader valve, but do realise you need to go for a drive at full throttle and run it through the rev's to see if it starts to lose pressure under load.

[BillC]

My xr8 was doing the same and it turned out to be the alternator. It was only charging enough to be able to start the car but when running most of the time the voltage was below 11 volts. None of the sensors like this. Put a new alternator on and all went good from then on.

[madmelon]

Thanks all! I've already replaced the fuel pump- it's only 18 months old at best and is a Walbro 341/342 (Can't remember which specifically but it doesn't matter).

I pulled the plugs when I did my oil change and, as expected, covered in that rust coloured crap from the octane booster. At that point, I'd run half a tank through without the booster but the plugs showed no sign of carbon deposits at all- only thing on there was the orange crap. If I had to guess, I'd say a lack of fuel. As to the cause, hopefully Ford can figure it out tomorrow. If they can't sort it then I think it'll be off to C&V or Autotech...
Need car ready for 29th of Apr track day and have just dropped 3 grand on other bits so it can be! :(

[madmelon]

Just remembered another symptom- if I was giving it WOT and it wasn't pinging, at the completion of a shift going back to WOT, it would sometimes ping briefly again. Like there's a problem with WOT enrichment. Makes me think even more that it's a fuel problem of sorts.