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Very bad fuel economy VN V8

Noy

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Ey guys just put $40 of 98 octane premium fuel in, which was 31 litres or something like that. So far ive only done 80k's since filling up and im already on red line. I also just serviced the car oil change/filters/leads and sparkplugs, I did the leads and sparkplugs due to it was jerking/missing while driving that problem went away but now seems to be haunting me again.

Any ideas on what this could be? I was thinking maybe a leaking injector.. car is virtually stock as a rock CAI and exhaust system.

Cheers:thumbsup:
 

dufus

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I have an idea............

Search :thumbsup:
 

8rody

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The gauge is accurate yes? :p

If you can, get the car up on ramps and run it for a bit. Check all the steel fuel lines from the fuel tank to the engine bay for pinhole leaks. Check all rubbers.

Check the fuel rail for leaks.

If all is a-ok, its it's likely leaking injector, or a dodgy sensor (oxygen sensor for example) that is causing it to run really rich.
 

delcowizzid

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oxygen sensor and coolant sensors are a good start and a new thermostat of the correct temp and check the base timing
 

Noy

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Hmm Im more pointing towards the coolant sensors, as going by the gauge its over cooling which results in more fuel consumption yeh?
 

delcowizzid

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if its not warming up or not warming up fast enough will cost a lot of fuel.thermostat and ecu temp sensor will be a good start
 

88GreenVN

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Ey guys just put $40 of 98 octane premium fuel in, which was 31 litres or something like that. So far ive only done 80k's since filling up and im already on red line. I also just serviced the car oil change/filters/leads and sparkplugs, I did the leads and sparkplugs due to it was jerking/missing while driving that problem went away but now seems to be haunting me again.

Any ideas on what this could be? I was thinking maybe a leaking injector.. car is virtually stock as a rock CAI and exhaust system.

Cheers:thumbsup:
31 Lts will get you 200k's or so. The missfire could be dizzy cap/rotor button - as you have changed leads and plugs. A leaky injector probably wont give a missfire. A blocked injector may do so - but would probably have a miss at idle.

Id start with replacing the O2 sensor and temp sensor as Delcowiz said ^^^ first and check the contacts on the rotor button/dizzy cap.
 

Noy

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Cheers guys, yeah going to go to holden tommorow and buy an O2 sensor and temp sensor.. holden stock them still yeah?
 

greenfoam

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Is it an auto and if so is the torque converter locking up
 

immortality

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if the coil is original it may be time for repalcement as well. also check the static timing on the dizzy. may not be your problem but can't hurt to check anyways
 
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