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My Study: Simple Tips & Tricks to improve fuel economy on VS

PlenumBiscuit

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So ive bought a VS, I love it but am a bit down on the fuel use compared to my old VL. I figured the technology of a 1995 car that is 10 years younger would have supreme fuel use compared to the 1986 commodore, but still, one is a 3.8 litre & the other is a 3.0 litre

ANYWAY, im researching around the internet & putting together a list of tips and tricks to save fuel on the VS. From at home jobs to advanced mods

Please reply & tell me more if you like, I'll edit the list as we go

Lets not discuss my fuel use per kilometer, lets just list every trick....

Here is the collection (some being very obvious)...

# Dirty Air Filter - renew
# Dirty Mass Air Flow Sensor (MAF) - Clean with proper MAF Cleaner (also helps if running rough)
# Tighten all clamps ensure sealed no air leaks

# Polish throttle body - remove all black gunk - VIEW MORE
# Clean IAC - remove black gunk or renew
# Secure all clamps on throttle hoses, ensure no air leaks - i personally got new hoses very cheap at Sprint Auto

# Polish/degrease Plenum Chamber - likely coated with oil - clean so oil free and incoming air isnt heated by hot oil in your plenum
# Secure all clamps on hoses at back of plenum chamber, ensure no air leaks

# Check Exhaust manifolds for cracks or air leaks (very common)
# ensure nuts on manifold are tight. These come loose on most cars over time

# Oxygen sensors are a huge culprit to poor fuel use - renew
# Many known issues with earths on O2 sensors on some vehicles - Earth oxygen sensor wiring from the ECU straight to the chassis -READ MORE HERE
# Another solution is to disable the heater wires on the O2s (pink wires) - please study before attempting this
# Even check if your O2 sensors are in tight

# Replace the Coolant Temp Sensor - incorrect readings to the ECU will cause poor fuel use

# (immortality) With a can of contact cleaner, remove & clean every electrical connection, even polish up the earth points

# Ensure wheel alignment is correct & tyre pressure is always correct (my stock 15inch tyres are 38psi)

# New spark plugs - $25
# Test resistance of Spark Leads, renew if quite old, even a used set from wreckers $12 U-Pull-It

# Add injector cleaner to fuel
# Check if injectors arent leaking fuel, get new Orings securely seal
# get VT injectors (the green ones) they hav a better spray pattern and design. Will require a memcal tune so the ecu knows of the new injectors

# Get a memcal tune (new Computer chip settings) to suit VT injectors
# New fuel filter
# Secure all clamps on fuel tank hoses, ensure they arent brittle & not leaking fuel. Especially if u can smell fuel in the car or near back driver tyre

# An old Fuel pump could be causing poor fuel use.
# ensure return line in still on inside the fuel tank else car on corners might be stalling

# Add injector cleaner to fuel, or run on premium fuel occasionally, even a dose of 98 Octane will clean her out. Some people use 98 octane permanently.

# Replace charcoal cannister, or clear SEE MORE HERE
# put clamps down on these hoses on the cannister too

# (from jonah101) Get brakes serviced, make sure the brake sliders are free and its pistons are not sticky.

# Turn off your Air conditioner

OTHER GENERAL TIPS TO MAKE VS PERFORM WELL

# Get fatter earth cables to the engine. Upgrade cable from battery to body (she'll start faster). Also add a fat earth cable from battery (negative) to engine block (in front of block where heater bolt is & a small earth wire currently sits) super cheap auto sell heavy lug battery terminal cables

# (from Brett_jjj) Service Auto Transmission every 50,000, change filter & trans oil

# (immortality) service/change all oils and filters (don't forget the diff oil)

# Check the oil pressure sensor isnt busted and leaking oil (unplug it and check)

# Renew the Alternator main wire & larger battery earth wire

# Add Carbon Clear to the oil (dont know what the products name is see in store)

# Get a memcal tune (new Computer chip settings) for better throttle response (contact The1 on this forum)

UPGRADE THE ENGINE (Mods)

# Install a Cold Air Intake (CAI) for ultimate air into the engine

# (Brett_jjj) New set of headers (extractors) makes a good difference over the standard setup - $400

# (immortality) I'd also recommend some diff gears, 3.45 works well, (transmission upgrade)

# Add Plenum Chamber Spacer?? True or false??
VIEW HERE


Please tell me more??
 
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Brett_jjj

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As long as everything else is spot on, then a decent memcal tune will give the best fuel economy benefits. Also a set of headers (extractors) makes a good difference over the standard setup. Id also add to your list servicing the auto trans (if auto) every 20,000 km or so, and get a decent wheel alignment every 12 months or so. All these small little things all work together to give excellent fuel economy..
I can get around 6 L/100km in my VSV6 on the highway, and around 9 -11 around town. I only use 98 octane fuels, as they give the best fuel economy. I found that I can go the same distance on $20 worth of 98, as I can on $20 worth of 91 octane fuel, even though I get a litre or two less fuel for the money with 98 fuels.. A few times Ive even had it go further than it would have on the same amout($) of 91. Ive got a mostly standard ecotec, except for pacemaker extractors and my own memcal tune..
 

mpower

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free flowing exhaust system will improve economy and improve performance.
 

Immortality

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Start with a good service, that is everything, all oils and filters (don't forget the diff) and clean the MAF, make if part of every service for good measure. I generally do it once a year or every 2nd service.

Plugs and leads (if they are old), maybe coils if they are the original ones (use genuine replacement coils though).

Some fuel injector cleaner. consider the later type injectors as they have a better spray pattern although ideally you will want a retune to suit (talk to the use the1).\ and run injector cleaner regularly to ensure the injectors stay nice and clean.

Get the MACE cold air intake and manifold/plenum spacers. I have these and they do work.

Get good tyres, make sure you run the correct air pressures and a good wheel alignment.

O2 sensors, replace for good allround performance replace every 100,000km's. Yes, the VS does have a known wiring fault with 1 of the O2 sensors. only way to know if you have the fault is to data log the vehicle and see if they are both working correctly. Having said that, remove and clean all the wiring loom earth points on the engine just for good measure.

I'd also recommend some diff gears, 3.45 works well. the VS is ok if your driving around with only 1 person in it, but load it up and it starts to struggle a little (the MACE manifold spacers will help here also), load the car up with say 4 adults and it will very quickly start to feel like a slug as the little V6 lacks torque. my personal experience s that my VS (fully loaded) has better fuel economy at 130km/h that it does at 100-110km/h......

good to see you have grown up and moved on from the VL
 

PlenumBiscuit

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Thanks champs have added your tips in the Newly added section

(Brett_jjj) New set of headers (extractors) makes a good difference over the standard setup

how hard is this mate, on ebay extractors are $400 bucks??
is this what you mean?

(immortality) I'd also recommend some diff gears, 3.45 works well

thats in the transmission yeah? sounds like a massive massive job?
 

Deuce

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My 2 cents:
always run it on premium fuel, and get it tuned for it. (extra spark advance etc.)
Tyre pressures!! - check regularly, and increase the psi if you want improved economy on the highway.
 

mpower

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Also Mythbusters did a hypermiling episode just recently.

Windows up

travel at a lower speed on the freeway.

a/c off

stop and start engine at lights

brake gently, few things made a big difference.
 

Brett_jjj

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(Brett_jjj) New set of headers (extractors) makes a good difference over the standard setup

how hard is this mate, on ebay extractors are $400 bucks??
is this what you mean?

Yes, extractors/headers will eventually pay for themselves over time with the fuel savings they give.. I noticed a pretty decent saving from fitting them, although I cant remember exactly what it was now. I dont know how the cheaper brands would go, but I went with pacemeker brand, which were a bit more expensive than some others I looked at. I kept getting cracks in my standard manifolds, so that was another good reason.. As well as the fuel savings, I also noticed that the running temp of the engine dropped on the temp gauge, It dropped by around 1 mark in all conditions.
 

Immortality

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Diff gears..... are in the diff (under the back of the car....... (Between the rear wheels).........) :)

Yes, probably a job for a specialist if you don't know much about it.
 

monkeys437

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I got 3.45 diff gears a few years back and my fuel consumption went up a noticeable amount, but I do about 60% highway k's. I still get about 10.5L/100km but I used to get under 10 for the same type of driving. In my experience, I definitely wouldn't get diff gears for a fuel saving mod for an old V6. You'll make the most savings with driving style anyway, and the longer you drive a car for the better you'll get at driving it efficiently
 
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