GU 4.5 Tunning

[rodneyb81]

Hey Guys,

Live on the southside of Brisbane bought a 2000 4.5 GU knew they would be a bit hungry on the fuel but getting around 24 + l/100kms driving around town. I have done plugs leads air filter cleaned Maf and have new oxygen sensor have been told adjusting timing and clearances make a big difference to power and fuel is this true what sort of cost should I expect to pay anyone got anyone they would recommend ? Standard height normal size bfg wheels bull bar so roof racks pretty standard...

Been thinking about a gas conversion but with this consumption before conversion scared what it could be after....


Advice

Rodney

[threedogs]

They are thirst and 25/100 around town sounds about right. check tyre pressures every 2 weeks.
after you'll only be using gas so maybe 350-400 per gas tank

[lhurley]

Manual or auto makes a difference. I get about 25/100 around town on petrol. i have injected gas on mine, and i get about the same on gas. Its good when its 63c/L, but not as good when its 80c/L like it is now. Call up Derek at Auto Art at capalaba, hes is a gas mechanic. I got my tappets done by him and i got about 30% better economy and way more power. Admittedly they were sticking open, but i am very happy atm.

[rodneyb81]

Hi Ihurley it's an auto that seems to make it sluggish could drop down gears better when you try and go up hill instead of speedo going backwards at at a fast rate.... Any idea what they charged when they did the work in capalaba did he do you gas conversion too ? How much did your conversion cost if you don't mind me asking

[threedogs]

Probably looking at $2500 a conversion. sequencial injection is best for power,
As I mentioned before clean the MAF, sensor., For gas to perform at its best your
electrics ,leads etc, plugs need to be Spot on, If you do get a conversion make sure they use "Y"
not "T", makes a huge difference in efficiency

[twisty]

Probably looking at $2500 a conversion. sequencial injection is best for power,
As I mentioned before clean the MAF, sensor., For gas to perform at its best your
electrics ,leads etc, plugs need to be Spot on, If you do get a conversion make sure they use "Y"
not "T", makes a huge difference in efficiency

G'day3D,

Is the "Y" used for injection only? Where is the "Y" fitted?

[marmon007]

Hi rodneyb81........ I have a 99 gu 4.5 manual, and on open highway towing between Wagga NSW and Bribie Island (24ft cabin cruiser 2.4 tonne) I average 16.347 litres to the 100 klms. Previously it was around 24 to 26. I went to a guru mechanic and by hooking up the diagnostic he found that the thermostat was staying open and therefore the engine was too cool and auto choke was over fueling the engine. Fixed the problem and I am very happy. Marmon007 (Beau)..........I hope this is helpful

[NP99]

Hi rodneyb81........ I have a 99 gu 4.5 manual, and on open highway towing between Wagga NSW and Bribie Island (24ft cabin cruiser 2.4 tonne) I average 16.347 litres to the 100 klms. Previously it was around 24 to 26. I went to a guru mechanic and by hooking up the diagnostic he found that the thermostat was staying open and therefore the engine was too cool and auto choke was over fueling the engine. Fixed the problem and I am very happy. Marmon007 (Beau)..........I hope this is helpful

That's excellent mileage. Is the mech Brisbane based?

[nissannewby]

That's excellent mileage. Is the mech Brisbane based?

There's a good gas mech at capalaba. Not sure he would be open right now. :p

[NP99]

Where abouts Mat......I can wait until sunup :)

[nissannewby]

Where abouts Mat......I can wait until sunup :)

Hey Shane
Not sure of the exact address but its "auto art" and the blokes name is Derek I'm pretty sure either way he knows gas.