Econometer/Vacuum Gauge Installation Guide
 

This is also posted in my Metro thread, but I wanted to post it here in the instrumentation section for those interested in using a vacuum/boost gauge in their vehicle. This guide is for a 1998 Metro, but installation would be similar on most vehicles.

The new gauge is a "Vacuum/Boost" gauge made by Sunpro, but the only scale I can use on a non-turbo vehicle will be the vacuum side of the gauge.

http://i75.photobucket.com/albums/i3...tf/vcgauge.jpg

The first thing I had to do is find a proper mounting location and on my car, the spot on the column was perfect for a 2" gauge. I simply used the supplied self tapping screws and secured the mount to the top half of the column cover...............

http://i75.photobucket.com/albums/i3...tf/4216026.png

I then placed the gauge in place through the mount and ran the vacuum tubing and electrical wires for the gauge illumination behind the cluster cover so nothing is exposed.

http://i75.photobucket.com/albums/i3...tf/4216027.png

I simply removed the heater control cover plate and unplugged the bulb and spliced the illumination wires right into the harness so the gauge lights up when the cluster lights up.............

http://i75.photobucket.com/albums/i3...tf/4216031.png

The mounting and illumination is now complete. The last thing to do is to run the vacuum hose provided with the gauge through the firewall to find a vacuum source. I ran a long screwdriver through the main wiring harness boot and fed the tubing through the gap made by the screwdriver.

http://i75.photobucket.com/albums/i3...tf/4216033.png

I then adapted the connector to a vacuum source to monitor my fuel economy.

http://i75.photobucket.com/albums/i3...tf/4216022.png

Here it is all installed and in the normal driving position, nothing on the cluster is blocked................

http://i75.photobucket.com/albums/i3...tf/4216032.png

NOTE: The vacuum line was spliced into the large vacuum line at the booster originally shown in the picture, however, this was causing poor readings. I later spliced into the vacuum source very close to the engine for instant readings of the engine vacuum. After driving with the gauge, it actually tells you when to shift if you know how to monitor it and will also make it easier to stay easy on the throttle.

Johnny Mullet -

Most excellent! I just had my mechanic install one this week :

Vacuum Line Connection :
http://img176.imageshack.us/img176/3...tionrs1.th.jpg

Cheapy JC-Whitney Gauge
http://img176.imageshack.us/img176/8...augeqq3.th.jpg

It's on a cheezy Glow-Shift Gauge Pod, and then zip-tied to the dashboard cover.

At idle or in steady-state 5th, it reads a steady 10 In Hg. Is that correct? What should it be? Also, my cheapy gauge doesn't go negative like your Sunpro. I don't really know how to use it for shifting. I mostly got it to watch for engine problems.

CarloSW2

The way mine operates is kinda weird, but I have it figured out and use it to save gas.

Starting the car, the gauge reads about 15 at idle and as you accelerate the vacuum drops and the gauge can read almost zero at hard acceleration. During upshifting, you can actually watch the needle slightly raise in vacuum right at the ideal shift point and it's pretty closely timed with the dashboard shift light. When letting off the gas, the gauge will read around 20-25 depending on speed.

Once you are up to normal driving speed, it's up to you to find the sweet spot. On my particular setup, I get the best fuel economy at around 55 MPH and the vacuum gauge reading around 10 on the dial. I try to keep it there steady. The gauge is sensitive and will change with throttle position/load. I use this to keep a steady throttle position to save fuel.

engine vacuum is also a good indication of how healthy your engine is.

Mine read 21 @ idle, 15-17 @ 45mph, and 12-14 @ 65 mph, 23-25 under engine braking. It really helps because I can dial in the right amount of throttle very quickly for the speed I want to travel.

Negative boost FTW:thumbup:

I sprang for the autometer vacuum only one so it would match the oil pressure and other gauges ive collected along the way from modding cars. it was $45 on ebay. I think this is a great direct feedback tool for the driver who doesnt want to spend for the scangauge.

cfg83,

If you're getting 10 inches of mercury, either your engine is sick, or it's a bad vacuum source. Should be getting 15-18 at idle.

Is the needle steady? Does it bounce up and down, or slowly fluctuate? This gauge is a great indicator of both engine health and economy. Check a service manual or on-line reference for details about the readings.

The boost side is a waste of money, unless you have a turbocharger. Not a popular ecomod option...

I've run that gauge for 20 years and it's about the best fuel efficiency meter there is (for ICE).

azlar -

Thanks for the info. The needle is rock-steady so I am hoping it's a bad source. I'll do some homework and see what's up.

CarloSW2

Looks like the mechanic who did yours hooked to the PCV valve? I would find a source directly to the intake or closer to it.

Hello -

My mechanic used his professional vacuum gauge and it read 17 in. Hg at idle RPM. He tapped into the same connection my vacuum gauge is using.

Verdict: My vacuum gauge is crummy.

The Lesson: Don't buy cheapy Garage-Pro vacuum gauge from JC Whitney or you'll get what you pay for.

I'm working on getting a better V-Gauge.

CarloSW2

Wow. The old vacuum gauge I was using was an older one offered by JC Whitney and it did not even have a number scale on it, just a green "Economy" and a red "Power" display in it. I had no issues with it after 10 years of use in multiple vehicles until the needle fell off.

Johnny Mullet -

I ordered a couple of these last week and swapped one of them in :

http://ecomodder.com/forum/7771-post59.html
I got more than one because they're cheap and I want to be able to offer the option to my friends and family if they get the hyper/ecomodding/miling bug. The fellow I bought them from was also very nice. I think it is more accurate than the original one I got, but it also has an error. It is reading at the upper boundary of the "idle" zone when I am idling. As you can see in the above picture, the "off position" of the red needle is not in the white/zero area. That's what mine looks like when the engine is off. Since I have more than one, I was able to compare them. The other one I have is in the "off zone". Sooooooooooooooo, I plan to swap in the "accurate" one and see if I can turn the dial/background of the other one so that it is also reading accurately. This is actually stuff I like to do, i.e. get cheapy things and make them work better.

I still like the cheapy JC-Whitney one I originally got because the dial is more responsive (270 degrees versus less than 90 degrees). I might make my own custom "dial backing" if I have enough time to recalibrate/remap against a professional vacuum gauge.

Even when it's "broken", I am happy, because I learn something, :D .

CarloSW2

That is pretty cool! I do miss the "Full Swing" of my older gauge, but I never order anything on the internet and like purchasing from local businesses. I could not find one like that anywhere local, but I already got used to the Sunpro and is seems to be a nice, quality gauge.

Thanks for sharing.

All gauges are inaccurate, as Gene Berg once said... For diagnostics, you have to spend some cash for the good ones. For general driving, you just need to plug them in and get used to the readings. If it's a lot higher or lower than normal, start checking things out, otherwise the engine is doing as well as it did when you installed the device.

I have a half-dozen or so gauges in my Vanagon. Each tells a different story, but after you learn the car, you can figure out the best methods for efficiency.

Laurence

My bulb just burned out on my vacuum gauge, so I am going to pop in a new one tomorrow. I was thinking of using a red or blue bulb instead. Maybe.

One thing good about this gauge is it will warn you of any engine problems right away! I had a vacuum line break on me while I was driving and my gauge was acting funny. It was fluctuating rapidly at idle and was not reading right when cruising. After fixing the line, it's all back to normal.

Hi there

I have a 20 year old Volvo 240 automatic 2 litre 4 cyl , the gearing seems quite good 2000 rpm = <>60 mph although it is only a 4 speed box.

Just done 610 miles , 430 on highway speeds around 60 mph rest town stuff but little congestion it returned 29mpg.

Would this gauge be worth fitting as I could only use it for my throttle setting and not when to change gear ?

regards Paul

Yes, it helps you maintain a constant, even throttle at cruising speeds and will help you save fuel.

Yep, it's not only good for cruising speeds, but can help you maintain a steady acceleration to speed. Around town it really helps hone your eco-driving skills.

My '82 242 has one in a stock location in the center console. Looks good and is easy to read.

Hi guys

Thanks for reply , looking for one now.

Azlar - where did you take your feed from at the engine end , I don't want to upset any of the sensors/devices that may need the vacumn to work properly.

regards Paul

The best place to patch in a vacuum gauge is a close source to the engine intake manifold. The closer to the engine, the better. Sometimes you can find a plugged port in the intake where you can remove the plug and install the adapter from the vacuum gauge in it's place. Do not patch into the brake booster vacuum source since this will allow the brake pedal to become hard after shutting off the engine.

As long as your connections are tight, sensors should be okay. Mine has a t-fitting spliced into the line feeding the ECU. Was easy to run it back into the cabin without too many twists and turns. Doesn't seem to affect the computer.

Another good spot would be straight off the intake manifold. The port on the left is for the powerbrakes, the one on the right has a reduced diameter. Might be okay, but the middle is a full size connection. Just put a T in there and run with it.

The mounting was in an unused spot in the console. Bezel broke the other day, so need to find a new one..:( This gauge doesn't have numbers, but if you drive it for awhile it will still give you good driving knowledge. I should probably calibrate it one of these days using my tune-up vacuum gauge, but this works fine.

Hi guys

Thanks for all this , most useful and nice to get things rights first time !

Azlar wow your 246 don't half have some gauges , I only have the main panel shown on the left in your picture and the clock !
regards Paul

You should see my VW Vanagon. :D There's 3 gauges for just for temp (water/oil/cylinder head)!

Azlar

Well I have spliced my gauge in where you suggested and it does not work properly only reading 3 or 4 at the most.

This is the gauge :-

52mm Auto Smoke Vacuum Pressure Dial Gauge Meter Silver on eBay, also Dial, Dash Switch Custom'n, Interior Styling, Car Tuning Styling, Cars, Parts Vehicles (end time 28-Jul-08 14:00:54 BST)

Before I got around to fitting the gauge this happened.

My wife used the car yesterday and it did not run after starting , being doing that a bit of late , so she hit the throttle to try and catch it and I heard a bang under the bonnet but the car ran so I let her go out in it.
When this happened last time it blew the big rubber donut off that is between the manifold and the air-fuel control unit and it refused to start till I reconnected it.

When coming to splice the vacuum line into the middle pipe connector in your photo I found that the other end under the manifold was not in it's housing ? [ caused by yesterdays bang ? ] the flame trap for the PCV and yet the car could start and run ? strange ?

It took me ages to get that back in but finally did it and spliced in the t piece.

When the gauge did not work I though the pipe was blocked down to the flame trap but it is clear , if I unscrew the middle pipe connector in your photo the car will not start and yet it could with the other end of the pipe hanging in the air ? the only difference being the screw in part has a restrictor at the manifold end ? lot smaller than the pipe diameter.

I do not have the third pipe in your picture on the right I have what looks like a bolt in there so I am going to see if it is tapped all the way through and I can get a pipe adapter to screw into it.

regards Paul

Check for any leaks first. The hose and t-fitting size have to match, otherwise outside air is getting in.

If the third pipe is tapped through into the manifold, you're golden. It'll be straight vacuum. Check the threads and find a fitting that matches.

You might want to take your gauge into the engine bay and quickly unplug various hoses and plug them into the gauge and see what it reads. Pick the best source and put a T in it. But I think that third pipe will be your best bet.

My Stewart-Warner Vacuum Gauge
 

I just wanted to show off my latest addition to the quest for mpg...

This gauge was donated by my dad, who has had this gauge in many cars, trucks, & motorhomes spanning 35+ years. This is what you would call a quality gauge. I made a cover out of a black cap off an aerosol can and used a strip of velcro to secure it to the dash cover. The vacuum hose is actually routed under the dash pad, not on top of it like the picture shows. I ran the hose down the side and under the dash to the passenger's side, exiting out an existing plastic grommet in the fire wall. I did tap into the brake booster hose, but did so in the location directly off the intake manifold.

Here's a couple pics:

That's a classic! Very "retro" and it even has more chrome on it than your entire car!

More chrome than any three Metros! :thumbup:

Seriously, I think I am adding this to the project list.

1. Set my timing right
2. New radiator
3. New fuel filter
4. THIS

Boy, I have some work ahead of me!

Hacksaw -

Great Gauge! You made me Google Stewart Warner :

Street Rod Gauges, Stewart Warner

Here's a reference to the Motor Minder (maybe it's still in production!) :

Vacuum Gauges - Stewart Warner

CarloSW2

Hi there

Found parts to move pipe to spare connector on manifold this has had a small effect.

Now the gauge buzz's like mad between 6 and 8 when idling , hits about 10 when coasting and 0 when accelerating.

Now I suspect I have a good feed and actually have problems with the car and not the vacuum feed , of course it may still be the gauge and I have no other one to try.

How do you test/look for a vacuum leak ? how can something that is not there leak ?

Puzzled ????

regards Paul

First, I'd check the gauge on another car or put another gauge on yours. That will rule out a bum unit.

Finding a vacuum leak is a real bear of a project. Simple way to start is get a can of Carb Cleaner and squirt it at anyplace that air might want to get into the engine. Hoses, intake manifold gasket, brake booster, etc. If there's a leak, the RPM's will increase a bit.

If the reading is low, you can live with it. Maybe just how it's connected or a quirky gauge. The buzzing isn't too good, might want to check your valves. If one doesn't close properly you'll get a backflash from the cylinder that will disturb the incoming air.

Check out RWD - The Volvo Owner's Resource
Lots of help for your car.

Decided to go install one on my Metro...

MAYBE 10 minutes (have not hooked up bulb yet) -- MULLET!!! What am I missing on removing the heater control panel? 2 Screws from under at radio, 1 screw for the tiny dash piece.......... do I have to take the main cover from under the column?

The gauge mount clipped under the plastic behind the column like it was meant to go there. No screws required. Have it offset to the right of center... I like to see the spedo,,, but I only need the left. My vision is only impared of 70mph and above.


---Gauge was very fluttery, I pinched off the line to give it a buffer, and now it's as smooth as can be. Hovers around 23 at idle, normal but conservative driving up the road, looks like 10 is the goal. Higher rev shift points means less load on the engine.....

Shifting too soon makes the engine work very hard.

My car had no radio or cover. I pulled all four buttons straight off the heater controls and the top cover came right out! In there you will find how to wire in the bulb.

Here are what normal vacuum readings should be on a properly working gauge and a properly running engine.............

IDLE - 18-22
DECEL - 22-30
ECONOMY - 10-18
POWER - 0-10

The goal to saving fuel is to monitor it while at cruising speed. Keeping a constant reading like 10-12 will net the best results. While getting up to speed, but never accel hard so it drops below 5 because that is just a waste. Watching it at idle will tell you if the engine is running properly. The gauge should really not fluctuate at idle more than 2, but some gauges are not as accurate as others.

My pinched off line wasn't so effective after it got warm....

I went into my local NAPA, and they sell a inline "vacuume arrestor" it has about a 26gauge hole in the middle, works GREAT for leveling out the readings.

Tooting my own horn i have a brand new boost/vacuum gauge for sale in the FS area.

Vacuum Gauge at Idle with the ac OFF:
http://ecomodder.com/forum/member-no...dle-ac-off.jpg

Vacuum Gauge at Idle with AC ON
http://ecomodder.com/forum/member-no...ge-idle-ac.jpg

Youtube Video of 0-50 acceleration through the gears... held camera with left hand. Couldn't see the gauge while doing it.

http://www.youtube.com/watch?v=05xvvXrc40s

Reading Vacuum Guages "A La Henry - Ford That Is"
 

Some time ago, I was looking at modifying my gauge array into one of those Flat Screen displays, like this:

Nordskog Performance Products

My Fairmont Squire wagon just got back on the road, after 2 years of ground up restoration and swapping to an economical Inline 3.3L Six from the original 302-V8. Outstanding difference in fuel economy. A tankful lasts me 2 weeks! But I can do better, with a couple other easy DIY mods.

Well anyway, I went on a Search tear, and found some really excellent sites about Reading Vacuum Gauges. One of those is from one of Henry Ford's Early V8 models, and is a great great graphic of the different activities of the gauge with small notations below each:
efv8 - Tech Tips

If you click the combo box, you'll see a companion text to go with it.

Next was a more detailed and logical explanation on its functionality and how to troubleshoot your car's systems:
Using a vacuum gauge

If you right-click the purple check-box icon, you can download it as a PDF.

I'm in a home renovation mode for the next few weeks, so I don't have time to do the Car-tweaking that I want to, but it runs perfectly. I never moved the distributor during the whole time I was working on the body, and I'm not sure that I have the vacuum lines set up right, but the Original plugs were in excellent shape, since it was rebuilt 6 months before the donor car was totalled, at which time I got it.

Hope that vacuum picture helps someone. At least it makes a nice framed picture for the garage!:D

Noel, that is a perfect example of how to drive with a vacuum gauge and save fuel! Good job on the video!

I always accel between 0-1 inches. Seems to work alright for me and my little 1.6

I also just get me a cheap vacuum gauge, but i don't know were to install it. There's a T-splitter within the package but i don't know were to place it.

There is no manual whit it (bought it on the internet for 10 euro/15 dollar).

Here are pictures of mine:

T Splitter, under the air cleaner, I used the vacuum line that is on it's way to a sensor.

http://ecomodder.com/forum/member-no...ir-cleaner.jpg


Here is the Vacuum Arrestor that I got at NAPA to take the jiggle out of my gauge
http://ecomodder.com/forum/member-no...m-arrestor.jpg

Here is where I went through the firewall, that boot was pretty tough to get through, so I just went above it. There isn't much strain on the plastic, not too worried about it rubbing through. Might still add a piece of rubber fuel line over it to prevent eventual abrasion

http://ecomodder.com/forum/member-no...h-firewall.jpg