I know nothing about boosts/turbos

2003msp

Member
I really don't...if you read my intro thread you'd know my circumstances. But lets just leave it at this car was given to me.

it has these gages(the two on the left):

mrfguq.jpg



Can someone explain what these measure/their importance ect ect. Pretend like your explaining it to a seven year old, because thats probably my knowledge level when it comes to this

Thanks!
 
the one on the bottom measures your boost level ( not to be over 6psi
if it's stock ) the top one measures your air to fuel mixture looks like a narrow
band one though, not very accurate. does it say AEM on the top one?
 
start learning, for the sake of the car man.

The bottom gauge is probably a boost gauge -- it tells you how much psi your turbo is pumping into the engine. stock is around 5.5 psi (pounds per square inch. a pressure measurement), if you have a boost controller or other mods it may be higher, if that thing ever goes above ~8 I would let up on the gas, take it to someone who knows what they are doing and turn it down.

The top gauge is an Air/Fuel gauge -- it measures the mixture of air and fuel going into the engine. A "rich" condition would be something like 10 parts of air to every 1 part of gasoline (said 10:1, or just 10). A "lean" condition would be upwards of 17:1, and "stoichiometric" would be 14.7:1. Our cars get the most power when boosting at about 12:1. If you are flooring it and your boost gauge is reading boost the car should go a little rich (10-11, MAYBE 12), if you're off the gas and coasting or normal driving it will be higher. Basically, if this ever goes to 12 when you're going fast, be cautious. and if it goes higher than that STOP and figure out what's up. you'll blow your engine past that.

hope you understand that, it's pretty simple. watch the gauges, understand them, but also keep your eyes on the road :). happy learning.
 
the one on the bottom measures your boost level ( not to be over 6psi
if it's stock ) the top one measures your air to fuel mixture looks like a narrow
band one though, not very accurate. does it say AEM on the top one?

it looks like a wideband to me...
 
start learning, for the sake of the car man.

The bottom gauge is probably a boost gauge -- it tells you how much psi your turbo is pumping into the engine. stock is around 5.5 psi (pounds per square inch. a pressure measurement), if you have a boost controller or other mods it may be higher, if that thing ever goes above ~8 I would let up on the gas, take it to someone who knows what they are doing and turn it down.

The top gauge is an Air/Fuel gauge -- it measures the mixture of air and fuel going into the engine. A "rich" condition would be something like 10 parts of air to every 1 part of gasoline (said 10:1, or just 10). A "lean" condition would be upwards of 17:1, and "stoichiometric" would be 14.7:1. Our cars get the most power when boosting at about 12:1. If you are flooring it and your boost gauge is reading boost the car should go a little rich (10-11, MAYBE 12), if you're off the gas and coasting or normal driving it will be higher. Basically, if this ever goes to 12 when you're going fast, be cautious. and if it goes higher than that STOP and figure out what's up. you'll blow your engine past that.

hope you understand that, it's pretty simple. watch the gauges, understand them, but also keep your eyes on the road :). happy learning.
+100
 
start learning, for the sake of the car man.

The bottom gauge is probably a boost gauge -- it tells you how much psi your turbo is pumping into the engine. stock is around 5.5 psi (pounds per square inch. a pressure measurement), if you have a boost controller or other mods it may be higher, if that thing ever goes above ~8 I would let up on the gas, take it to someone who knows what they are doing and turn it down.

The top gauge is an Air/Fuel gauge -- it measures the mixture of air and fuel going into the engine. A "rich" condition would be something like 10 parts of air to every 1 part of gasoline (said 10:1, or just 10). A "lean" condition would be upwards of 17:1, and "stoichiometric" would be 14.7:1. Our cars get the most power when boosting at about 12:1. If you are flooring it and your boost gauge is reading boost the car should go a little rich (10-11, MAYBE 12), if you're off the gas and coasting or normal driving it will be higher. Basically, if this ever goes to 12 when you're going fast, be cautious. and if it goes higher than that STOP and figure out what's up. you'll blow your engine past that.

hope you understand that, it's pretty simple. watch the gauges, understand them, but also keep your eyes on the road :). happy learning.

So basically the boost gage is really just useful if I'm driving at a speed where the turbo would infact be pumping a a high psi?

and the air to fuel ration is also just to look out for the engine while its really getting worked?
 
So basically the boost gage is really just useful if I'm driving at a speed where the turbo would infact be pumping a a high psi?

and the air to fuel ration is also just to look out for the engine while its really getting worked?
you can use the boost gauge to tell if you have a boost or vac leak too
 
yup, yup, and yup. Both are very useful for trouble-shooting, and basically just used when you're pounding on it.

1 more thing, the boost gauge should read ~20-22 mmHg (vacuum) when you're at idle.

Is anything else done to your car? If you're not sure you can post up a picture of the engine bay/under car and we can pick it apart for you :)
 
yup, yup, and yup. Both are very useful for trouble-shooting, and basically just used when you're pounding on it.

1 more thing, the boost gauge should read ~20-22 mmHg (vacuum) when you're at idle.

Is anything else done to your car? If you're not sure you can post up a picture of the engine bay/under car and we can pick it apart for you :)

my vac is at 18 and i have replaced all the lines(scratch) any ways post up those pics
 
that pic was taken in 05, only 2 years and the steering wheel is beat up already...... someone didnt treat it right before you, poorrrr baby
 
yup, yup, and yup. Both are very useful for trouble-shooting, and basically just used when you're pounding on it.

1 more thing, the boost gauge should read ~20-22 mmHg (vacuum) when you're at idle.

Is anything else done to your car? If you're not sure you can post up a picture of the engine bay/under car and we can pick it apart for you

Thanks, you guys have been really helpful. I too live in Austin, TX, if I have any problems with the car, do you know a good mechanic near by?

that pic was taken in 05, only 2 years and the steering wheel is beat up already...... someone didnt treat it right before you, poorrrr baby

The pic is recent, the camera date is off. Its actually in really good condition!


Anyways, i will post more pictures soon, the car is currently in Houston (3 hours) away, I went to pick it up and drive it back last Monday, but the exhaust was broke. Basically the high heat and vibration from the turbo just ended up breaking a part, but its taken care of now, and somebody is driving it up hopefully by Saturday
 
a broken exhaust from high heat and vibration? highly unlikely... especially with the stock hangars, they are a very malleable rubber. Mayyybe the stock mount was shot and that put stress on it...but that sounds fishy. whatever.

Places in austin... Premier Mazda has always been good to me for warranty stuff and little things. JC Auto Spec is Corky Bell's place down there, it's up north. Also Austin Performance. Ive visited Corky's place but have never got work done there.... ive heard good things about both places, but i usually just do my own work.
 
a broken exhaust from high heat and vibration? highly unlikely... especially with the stock hangars, they are a very malleable rubber. Mayyybe the stock mount was shot and that put stress on it...but that sounds fishy. whatever.

Places in austin... Premier Mazda has always been good to me for warranty stuff and little things. JC Auto Spec is Corky Bell's place down there, it's up north. Also Austin Performance. Ive visited Corky's place but have never got work done there.... ive heard good things about both places, but i usually just do my own work.

Thats what the mechanic told me the most likely cause was...idk though


Okay good to know. How about Mazda South, they do work on my brothers Mazda6 and there customer service is great
 
yea they're getting better. They were dick heads to me a few years ago and Premier stepped in and helped out big no questions asked, so i always go to premier; although i know the owner of mazda south now and i have a friend who works there... so they may get my business in the future.
 
So i took it out for the first time today, and it drives smooth but when I shift and stuff I'm hearing a squeeking noise in the back, its weird. Thats a pretty general description but do you guys have any idea what might be up, it also feels as if the suspension sucks, could that have something to do with it?
 

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