AU Series 3 wagon question

[imbhvn]

Hey guys, i have an au series 3 wagon, i bought it off a mate of mine, the problem i have is that it only gets 300 km to a tank of fuel, i have replaced the oxy sensor, the sensor on the side of the throttle body, i've cleaned the throttle body and reset the ecu, but the problem still remains, it doesn't blow any smoke and it also runs/idles smooth, has a slight missfire every now and again though, i haven't changed the map sensor, as i've been told if thats buggered then it'll blow black smoke?

also has new leads and plugs

I would really like to fix the problem as my girlfriend is pregnant and cant afford to be spending 150 dollars a week on fuel!

Could anyone help me out?

Would be greatly appreciated.

Thanks in advance.

[JK EX CHASER]

Replace thermostat it might be open or jammed.

[Day-mow]

also check out air filter. proabaly done this but yeah.

hope it gets better.

[Bushbasher]

Chuck a bottle of injector cleaner through the tank as well. Your misfire could be as simple as old spark plugs or possibly leads. Find out when these were last changed, if ever, and maybe replace both. After that you might want to look at the cat; if it's buggered that'll make a big difference.

Bushbasher

[T3man]

collapsed (blocked) cat convertor
blocked air filter
faulty temp sensor
faulty fuel injector

[JC]

How many kms? If 100,000+, the first on T3man's list is my guess. Worth replacing thermostat as well (cheap, and could be the issue).

[imbhvn]

its done 250000 k's, air filter is new, as ar leads and plugs, i heard if the cat convertor was blocked it would die in the *** at top end? it pull right through the rev range, so i couldn't imagine that being the problem?how long should an au take to get to operating temperature??? because if my thermostat is stuffed it'll take longer if its jammed open, mine take about 10 minutes driving before its at operating temp. is there a way of testing if the temp sensor is shagged?

Thanks for your help

[JC]

Temp sounds normal. Blocked cat usually is more noticeable up to about 2500rpm (sluggish), but then should go better after that.

Have you had a scan tool on it? For $50 min charge at most workshops, it will tell you if a sensor etc has failed - easier and can be more cost effective than just replacing parts willy nilly.

[imbhvn]

No, i havnt had the ecu scanned as of yet, i was hoping there was a way to bridge the computer and it tells you the faults that way??? if i took it into ford they will most likely charge more than 50 yeah?

[JC]

Originally Posted by imbhvn

No, i havnt had the ecu scanned as of yet, i was hoping there was a way to bridge the computer and it tells you the faults that way??? if i took it into ford they will most likely charge more than 50 yeah?

They have only ever charged me minimum charge ($50). And no, no way i know of to do the bridging thing.

[Bobman]

Thermostat is pretty common. Mine takes a while to get into the [normal] range & will be replaced soon, but I'd replace yours anyway on yours if you are unsure of when it was last done (if at all).

[imbhvn]

I chucked a bottle of injector cleaner in, seems to have gotten rid of the missfire, will see how the economy is now, if still **** will gey the ecu scanned for faults. Is anyone selling a wagon fuel pump/ sender unit as mine goes from 3/4 tank straight to 1/4 if so how much?

[imbhvn]

What should the temp sit at? Mine sits between the n and tje o in the normal part

[frd906]

That sounds normal

[Mr Hardware]

Yeah most people's sits just shy of the o.

[imbhvn]

Okay, well im gonna check out the cat if thats fine, its going to the shop!

[Day-mow]

Good luck if you are strapped for cash. Might be worth going to a wrecking yard and find a low km one and take that.
Just an idea.

[imbhvn]

Hey guys, just had my wagon running infront of my brothers car with the aircon on, and theres all black soote looking stuff over his bumper bar, could this be cause from the map sensor? is it possible the cat convertor is causing this?

thanks in advance.

[frd906]

Could be, ony way to tell is to unbolt it off the car and see if anything falls out

[T3man]

temp sensor

[imbhvn]

Where abouts is th temp sensor? Im asuming the temp sensor doesnt operate the temp gauge? Because the gauge reads normal

[frd906]

Temp sensor is on the back of the head, you can see it from the drivers side of the engine

[T3man]

Like he said - kinda high at rear of engine ... the temp sensor tells the ECU the coolant temperature so it can trim the injector cycle for cold starting. If it is buggered the ECU will overfuel - might explain high fuel usage and soot out of exhaust at idle. Get a workshop to test the CO reading at your exhaust - they'll soon tell you if it's running rich or not.

[imbhvn]

Thankd heaps for your help! Greatly appreciated.