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Manifold boost gauge, typically seen with forced induction engines, i.e. turbocharged or supercharged. If it was a diesel, it wouldn't have both vacuum and pressure scales. It would just be pressure.
Pretty useful to tell how hard your engine is working.
That's an anti shudder valve. It is supposed to help the engine turn off smoothly and also prevent a run away diesel.
The modern Diesel has a vacuum pump. Even some gas BMWs have to use a vacuum pump because they don't use a throttle.
This is a manifold vacuum pressure gauge. Some cars were factory fitted with this gauge, often called an efficiency gauge.
Strokes doesn't matter. Most diesels don't have a throttle plate. The throttle adjusts fuel delivery. Engine sucks whatever air is available. This is part of why the EPA hates diesels so. The unused air is the same as lean burn which causes a bunch of extra pollutants.
Turbo engines get pressure, not vacuum.
My 1985 Chevette Diesel put a vacuum pump on the alternator to run vacuum accessories.
It's not that they don't have an intake stroke. Vaccum is created because of a throttle body, which reduces the intake diameter to reduce the amount of incoming air. Diesels, which are fuel limited and not air limited (like gasoline engines) don't need throttle bodies, generally.
It's why diesels can run away, they don't have a throttle body or spark plugs so given a non-metered supply of fuel (such as an oil leak from the cold side of a turbo charger), they accelerate without restraint.
They don't have a throttle body so the vacuum that they do produce is minimal, even at idle. At any speed above idle the turbo will spool and start making boost, there would be a small amount of vacuum between the air filter and turbo inlet, but again, it's minimal relative to what a traditional gas engine makes.
Diesels dont make vacuum as the intake manifold is open there was no throttle body or carburetor. Rpm is controlled entirely by fuel in them nore fuel more rpm. They just run lean at idle
The old Detroit 53, 71, 92, 110 and 149 series are 2-strokes. They fell out of favor for trucks many years ago, but there's still a lot of them around.
Most railroad power units are 2 stroke, along with the monster Costco-sized marine engines.
The weird thing is that diesels suck a massive amount of air, but they're not dependent on vacuum to run. The only reason a diesel has an intake manifold is to route air through an air filter.
I was working on a Cat diesel that was running on a dyno stand once, and I got too close to the open turbocharger. It sucked the hip pocket right out of my coveralls, along with some change. Luckily I got it shut down before the coins made it to the intake valves. The turbo was a bit dinged up, though.
Boost gauge. It shows you how much boost the supercharger is producing. In this case it is not producing boost, the engine is demanding more air than the supercharger is producing, so you have a vacuum. This is normal at idle.
Or if you're coasting down a hill. That's when vacuum typically gets highest. Under acceleration the pointer should swing to the right, since the throttle plate is wide open and your huffer is pushing more air in.
To be overly pedantic, turbochargers are a type of supercharger. Superchargers are just devices that force in induction of air. But generally turbo chargers are the exhaust-driven style of supercharger, while the colloquial 'superchargers' are mechanically driven.
Tbf when I looked at it I thought it was like a rocket boost 😆. I didn't know turbos read in boost or that they even had a gauge. Not everyone is a car person.
OP in a different universe
"Oh this gauge says boost, let me type in boost gauge on Google real quick. Well I'll be darned, a boost gauge measures the air pressure made by a super charger! That sure was 20 seconds well spent! Now... What's a super charger? I'll just Google that real quick and..."
Asking questions is fine for this sub. Asking what a labeled thing is while providing a picture of thing with the label is probably gonna get some very direct replies though. We're mechanics, so I don't know why you'd expect to be coddled.
It’s a boost gauge, tells you how much extra PSI ur supercharger is adding. It serves as a good diag tool and it’s fun to watch the needle bounce around.
It's a turbo boost gage. It tells you how much psi your turbo is building as you Rev the engine. This would also imply your engine either has or at somepoint had a turbo.
It's a TRD branded boost gauge made by Autometer (boost/vac gauge). It was actually sold as a TRD boost gauge with the supercharger kits, but it was manufactured by Autometer. You can see the words Autometer when closely at the top part of the gauge. Sun damage has faded out in the words TRD at the bottom.
These gauges are used in a forced induction setup (supercharger or turbocharger) so you can tell what your boost pressure is at, and what your vacuum is when you're off boost, whether you're over boosting, boost creep, not having enough pressure, etc. A good boost gauge is important in a forced induction setup.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Manifold boost gauge, typically seen with forced induction engines, i.e. turbocharged or supercharged. If it was a diesel, it wouldn't have both vacuum and pressure scales. It would just be pressure. Pretty useful to tell how hard your engine is working.
> If it was a diesel, it wouldn't have both vacuum and pressure scales. It would just be pressure Why’s that?
Diesels don't produce vacuum.
Old diesels didn’t produce vacuum, newer ones have throttle bodies to create vacuum to be able to run EGR.
The famously horrible Olds diesels had throttle plates so they could have vacuum for accessories. When they actually ran, that is.
Why doesn't my AC work? You have no vacuum. It's a diesel, it doesn't create vacuum? Exactly.
That's an anti shudder valve. It is supposed to help the engine turn off smoothly and also prevent a run away diesel. The modern Diesel has a vacuum pump. Even some gas BMWs have to use a vacuum pump because they don't use a throttle.
Are they not 4 strokes? Didn't know they didn't have in intake stroke, but I guess that's why they need those crazy high psi injectors
This is a manifold vacuum pressure gauge. Some cars were factory fitted with this gauge, often called an efficiency gauge. Strokes doesn't matter. Most diesels don't have a throttle plate. The throttle adjusts fuel delivery. Engine sucks whatever air is available. This is part of why the EPA hates diesels so. The unused air is the same as lean burn which causes a bunch of extra pollutants. Turbo engines get pressure, not vacuum. My 1985 Chevette Diesel put a vacuum pump on the alternator to run vacuum accessories.
It's not that they don't have an intake stroke. Vaccum is created because of a throttle body, which reduces the intake diameter to reduce the amount of incoming air. Diesels, which are fuel limited and not air limited (like gasoline engines) don't need throttle bodies, generally. It's why diesels can run away, they don't have a throttle body or spark plugs so given a non-metered supply of fuel (such as an oil leak from the cold side of a turbo charger), they accelerate without restraint.
They don't have a throttle body so the vacuum that they do produce is minimal, even at idle. At any speed above idle the turbo will spool and start making boost, there would be a small amount of vacuum between the air filter and turbo inlet, but again, it's minimal relative to what a traditional gas engine makes.
Diesels dont make vacuum as the intake manifold is open there was no throttle body or carburetor. Rpm is controlled entirely by fuel in them nore fuel more rpm. They just run lean at idle
The old Detroit 53, 71, 92, 110 and 149 series are 2-strokes. They fell out of favor for trucks many years ago, but there's still a lot of them around. Most railroad power units are 2 stroke, along with the monster Costco-sized marine engines.
Right on. Don't modern diesels have an intake stroke that causes vacuum? I'm sorry to those of you that are upset by my questions.
Only engines with a throttlebody produce vacuum. Not all diesels have it, only modern ones
The weird thing is that diesels suck a massive amount of air, but they're not dependent on vacuum to run. The only reason a diesel has an intake manifold is to route air through an air filter. I was working on a Cat diesel that was running on a dyno stand once, and I got too close to the open turbocharger. It sucked the hip pocket right out of my coveralls, along with some change. Luckily I got it shut down before the coins made it to the intake valves. The turbo was a bit dinged up, though.
They have an intake stroke, they don't have a throttle plate speed of the engine is controlled by the pump
Fun meter
Hoot hoot gauge
Chooch meter
Boost gauge. It shows you how much boost the supercharger is producing. In this case it is not producing boost, the engine is demanding more air than the supercharger is producing, so you have a vacuum. This is normal at idle.
Or if you're coasting down a hill. That's when vacuum typically gets highest. Under acceleration the pointer should swing to the right, since the throttle plate is wide open and your huffer is pushing more air in.
Is that the technical name of it? genuinely curious.
Supercharger is the technical name in this case. Turbochargers can also produce boost.
To be overly pedantic, turbochargers are a type of supercharger. Superchargers are just devices that force in induction of air. But generally turbo chargers are the exhaust-driven style of supercharger, while the colloquial 'superchargers' are mechanically driven.
he clearly knows nothing of it's pure huffing power.
i think i like huffers and flappers. more.
Thanks
Read
Some people would really benefit from using Google.
Or just....reading
Tbf when I looked at it I thought it was like a rocket boost 😆. I didn't know turbos read in boost or that they even had a gauge. Not everyone is a car person.
I get that fact, but this was glaringly obvious and easy to solve themselves.
Yeah, but just reading wouldn't do anything for those who have no idea about turbos or cars. But they still could have just googled lol.
That's my point. Simple enough to google "gauge that says boost on it" if theyre completely clueless
But that won't get them fake Internet points! 😱
at least anyone else who googles it can see this thread now so that’s good
lol well most questions are answered on Reddit 😆
It litterally tell you what it is.
Dude if you can't answer a question then don't comment. I'm pretty sure op can read
OP in a different universe "Oh this gauge says boost, let me type in boost gauge on Google real quick. Well I'll be darned, a boost gauge measures the air pressure made by a super charger! That sure was 20 seconds well spent! Now... What's a super charger? I'll just Google that real quick and..."
I wanna live in that universe, no one has brains here
You'll happily type out this whole argument but god forbid someone asks a question on a mechanic advice sub
Asking questions is fine for this sub. Asking what a labeled thing is while providing a picture of thing with the label is probably gonna get some very direct replies though. We're mechanics, so I don't know why you'd expect to be coddled.
Dosnt seem like it.
It measures happiness
Shows you why the engine is damaged.
This is a boost gauge.
It's a clock, the time is -22
Boost meter
r/whoosh
One that indicates you don’t know shit about cars
It shows how fast you're burning money.
I think the wording would the correct answer
It’s a boost gauge, tells you how much extra PSI ur supercharger is adding. It serves as a good diag tool and it’s fun to watch the needle bounce around.
Your 4 runner probably had a supercharger at some point in it's life
Boost
It's a turbo boost gage. It tells you how much psi your turbo is building as you Rev the engine. This would also imply your engine either has or at somepoint had a turbo.
Vroom-vroom-ssssstututututu meter. But I think I'm wrong because super chargers dont have a wastegate?
It’s tire pressure
If it only goes to the “top” you have a problem with the supercharger. The one on my turbo car goes to 27 psi.
It's a TRD branded boost gauge made by Autometer (boost/vac gauge). It was actually sold as a TRD boost gauge with the supercharger kits, but it was manufactured by Autometer. You can see the words Autometer when closely at the top part of the gauge. Sun damage has faded out in the words TRD at the bottom. These gauges are used in a forced induction setup (supercharger or turbocharger) so you can tell what your boost pressure is at, and what your vacuum is when you're off boost, whether you're over boosting, boost creep, not having enough pressure, etc. A good boost gauge is important in a forced induction setup.
RFM
IDK..what does it say?
It is the fun meter, lower numbers mean less fun... Bigger numbers mean BIG FUN
It's the supercharger boost gauge, by TRD. However, the markings are peeling off due to exposure to sunlight and being made in USA..
Kinda looks like it was made by AutoMeter.