Poor Fuel Usage - AU S1 VCT

[FAT245]

Hey Guys,

Ive been trying to trouble shoot this for awhile,

Scanning the computer shows no codes but i am getting 22.8L/100KM when Driving around the city and it wont go under 14L/100 Highway driving.

I have changed O2, Injectors, Plugs, Coil, Leads, Fuel Reg & Pump, Cam Sensor, Crank Sensor and its still doing it.

My Mechanic and I are wondering if it is the MAP Sensor, my engine builder told me that it is a Common Issue on the Series 1 Engines?

Nathan

[Maka]

G'day Fat245, can you smell fuel or any black smoke out the tailpipe? Is it chugging or missing? No codes being thrown makes it hard aye lol! Where's the temp needle sitting when warmed up? Thermostat stuck open? (throw your dash into diag mode to see what the temp is in real time- please use Google or use the AFF search function to find out how if you dont know), fuel leak somewhere, air filter dirty? You are not using e10 are you?

Coolant temp sensor on the back of the head could be a culprit not sure, au's have a iat sensor in the intake manifold which could be covered in oil doubt it if your motor is in good nick - earlier falcons had a map sensor on the firewall. Is the o2 sensor a cheapy? It could be faulty, its not unheard of. Maybe do another ecu reset?

Sorry for all the questions i feel like Dick Tracey lol, theres enough suggestions there to keep you busy mate! Hopefully other member's could offer their expertise too- theyre pretty cluey lol!

cheers,Maka

[FAT245]

I can't smell fuel but the tail pipe is black as. Its not missing but the engine is rough at idle and sometimes stalls when i go full throttle and i have to back off for it to recover, does this more so when the aircon is on.

When all this is happening, the needle never moves from the \ before NORMAL, No Fuel Leaks, Filter is new, and i always run either 95 or 98.

We have cleaned the BBM with the Subaru Upper engine cleaner.

O2 Sensor is a Genuine Bosch Unit and ihave tried it in another car with no issues.

ECU Resets do not seem to make a difference either.

Thanks for the Help Maka.

Nathan

[T4ME]

Has the catalytic convertor been checked?

[FAT245]

Brand New Magnaflow cat

[T4ME]

Tried another ECU?

[FAT245]

No,

I do not know what the original Catch code should be for my car.
It got replaced in an accident a few years ago and dont know what it should be.

[T4ME]

Ill find it for you.

edit:here it is....

AU:

WABF - AU Dual Fuel Auto.
WACG - AU Auto Series 1 VCT
WANA - AU Auto
WAKD- AU GHIA SERIES 1.5 VCT (SMART SHIELD)
WTAB - AU XR6 Manual
WTLB - AU XR6 3.45 Manual - June 99 - Feb 2000
X2CA - AU1 TS50
Y3EC - AU1 XR8 Auto (Adaptive Shift)
Y3DF - AU - 2001 - Auto XR8
Y3EC - AU1 XR8 Auto (Adaptive Shift)

[Maka]

Originally Posted by FAT245

I can't smell fuel but the tail pipe is black as. Its not missing but the engine is rough at idle and sometimes stalls when i go full throttle and i have to back off for it to recover, does this more so when the aircon is on.

When all this is happening, the needle never moves from the \ before NORMAL, No Fuel Leaks, Filter is new, and i always run either 95 or 98.

We have cleaned the BBM with the Subaru Upper engine cleaner.

O2 Sensor is a Genuine Bosch Unit and ihave tried it in another car with no issues.

ECU Resets do not seem to make a difference either.

Thanks for the Help Maka.

Nathan

Nathan, your au seems not to be reaching operating temp (too cold = rich mixture) - its supposed to sit in between n & o so you might have to check your thermostat or the ect (coolant temp sensor at the back of the cylinder head). Put the dash into diag mode to moniter real time coolant temp.

cheers, Maka

[FAT245]

Hey Maka, we have already done the thermostat.

Ill search for the Diag Mode

T4ME, thanks for that, The car is actually a S1.5 Ghia VCT. So it looks like i need the WAKD Code. Cheers!

[_Ben]

Intake manifold gasket? Mine was missing heaps and going through fuel, stalling in cold mornings etc.

[Day-mow]

wow. you make me feel really good about my 18L/100km flogging through the hills the other day.
cheers

hope you find your gremlin

[FAT245]

MAKA

[Casper]

MAP sensor failed on my AU1 VCT many years ago and I had the identical symptoms. I'd say thats your problem.

[Maka]

It wont hurt to have a look at your operating temp, have a look at the link but take notice what Casper say's

http://www.fordforums.com.au/showthr...iagnostic+mode

cheers, Maka

[FAT245]

Temp is stuck at 90.0 and has been there for an hour

[FAT245]

Casper, that is what my original conclusion was.

[Maka]

That rules the cooling system out, time to rip apart the bbm & inspect, test and maybe replace the iat sensor. Hopefully thats what the problem is, keep us informed of your progress.
cheers,Maka

[Casper]

Have you actually replaced the MAP sensor?
Also, does the car go into closed loop when you are in cruise control?

[FAT245]

i havnt replaced it yet.

Ordered one through my auto elec today.
Cant check Cruise Control as i broke the controls during ... road rage..

[FAT245]

While im at it, can anyone see if their fuel level drops to 1L when they take off?

I have a suttering and stalling issue when the car is under half a tank, I have changed everything except for the fuel tank so i dont know what is going on, but i noticed that when the car stutters/stalls the Fuel level has dropped to 1L then recovers when it rises?!

[dieseltrain79]

Inlet manifold gasket .