VT 304 High Fuel Consumption

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Chicken1
Posts: 2
Joined: Tue Nov 17, 2020 5:08 am
cars: VT SS

VT 304 High Fuel Consumption

Post by Chicken1 »

Hi Everyone

Very new to this forum apologies if this has already been covered
Basically I have a 1983 WB Ute and has a VT 304 195KW Sequential
Engine with a Turbo 700 Auto, my problem is of late my Fuel economy
Is terrible, I have had a few people service and tune the engine but never
Seems to fix fuel economy. I have had this setup for over 16 years and
I actually used to get pretty good fuel economy around 13L per 100km
I now struggle to be under 25L per 100km . I have been told to get
My HOLDEN COMPUTER ECU Unit reconfigured but can’t seem to find
Anyone that can do it . I’m in Perth Wa and would love to no who to go to
To get it sorted out . Or can I just by a new computer on EBay for $300
And swap it with mine , can anybody point me to someone in WA that can
Help me . Thanks in advance
Jeremy
Charlescrown
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Re: VT 304 High Fuel Consumption

Post by Charlescrown »

First thing I doubt it's got anything to do with the ECU. You can get the fault codes out by jumping a couple of pins on the diagnostic plug but if the check engine light is not coming on I doubt you'll find anything. I do know that the O2 sensors get lazy as they age and won't throw a code for sometimes years. I did see one years back where the owner took it to several workshops only to be sold heaps of parts that didn't fix it till they replaced the O2 sensors. They can be looked at on a scan tool to see how active they are. Cheap fix if it works. The other thing is I would check the fuel pressure. Hope this helps.
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Gampy
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Re: VT 304 High Fuel Consumption

Post by Gampy »

Jumping in the boat with Mr. Charlescrown ...

Obviously assuming proper tune ups.

Least likely is the ECU.

Most likely is mechanicals ... i.e.,
Heads - seats and guides.
Rings
Cam & lifters
Timing Chain

The weaker the motor the deeper the foot!
Intelligence is in the details!

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Chicken1
Posts: 2
Joined: Tue Nov 17, 2020 5:08 am
cars: VT SS

Re: VT 304 High Fuel Consumption

Post by Chicken1 »

Thanks Charlescrown and Gampy

Greatly appreciate Your thoughts and advice , I think no harm in starting with the O2 Sensors
And going from there .
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Gampy
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Re: VT 304 High Fuel Consumption

Post by Gampy »

Hows the injectors, they got the drips ??
Last edited by Gampy on Wed Nov 18, 2020 1:44 am, edited 2 times in total.
Intelligence is in the details!

It is easier not to learn bad habits, then it is to break them!

If I was here to win a popularity contest, their would be no point, so I wouldn't be here!
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antus
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Re: VT 304 High Fuel Consumption

Post by antus »

There has been a few threads similar with the fault found to be a broken fuel regulator where the fuel is leaking out the vacuum line and in to the engine making the car run super rich and wasting a lot of fuel. Obviously you wont see that on your fuel economy, but it depends how your measuring it (eg calculated by kms from a tank will show it, instant consumption stats wont).
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
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