Automotive Vibration Analyzers – Part 5 of 5 – PicoScope NVH Kit

Automotive Vibration Analyzers – Part 5 of 5 – PicoScope NVH Kit


This video is part 5 of a five-part series
on
automotive vibration analyzers. In this
episode we are going to be covering the
Pico technology NVH diagnostics kit
which in my opinion is the best
vibration diagnostic
tool setup available
on the market today, and considering
what you’ve seen in the previous four
episodes
where the the other NVH analyzers
are
being phased out or no longer supported, I
believe this is definitely one
of the best ways to go. Now
to use this kit you’re going to need three
main, well four, if you count the laptop.
You need four pieces of equipment; you
need a laptop computer
which you probably already have, you’re
going to need some sort of a data-link
USB connector that, i’ll talk about
those
in a little bit, you’re going to need
the Pico diagnostic kit that you can
get
from picoauto.com, and then
you also need some sort of the Pico
oscilloscope in the 4000 series
so it has to start the number 4. This
one is a 4423 so it is a 4000 series, it is a 4
channel oscilloscope and
you can have a two channel oscilloscope
also
I’ve got a 4223
oscilloscope right here, but
both of these will work, they have
a Pico oscilloscope
module that through a USB cable connects
to your your laptop in turns your laptop
into a fully functional
high-resolution, high-speed oscilloscope,
and there some free software that you download
from
pico technology and
you can use this as an electrical
diagnostic tool for
electrical problems on a car
and here’s the four channel
version of it also, so
you’re going to need either a
two-channel right here, or a four-channel
oscilloscope. Both for these have a USB
connection that
just simply all plugs into the laptop
computer, the driver for the interface
comes with the NVH
I’m sorry, the Picoscope software from
the Pico website. Okay
now, we will use the four-channel
scope, but whether it’s the four
channel scope for the two channel
scope we are going to use the second
input terminal channel B for
vibration diagnosis. And so
What we do here is: you download
the software from
Picoauto.com, their diagnostic
the software, once that’s installed then
you’ve got the proper driver to install
the
the Picoscope so we will plugin the USB
cable and
plug that into the laptop,
and it will install the driver. There’s
red light here on the end
indicating that its active and
good to go, alright, then you’re also going
to need,
if you recall from episode 2 and
episode three of this five-part series, I
told you to
diagnose vibration problems on
automobiles, trucks, heavy trucks,
we need to know engine RPM and we need
to know vibration frequency
at a bare minimum; and
I showed you some software that you had
to manually record what the engine RPM
was
and then get the vibration frequency
from whatever tool
you had, and match those up on a a graph,
and it would
to show you what group
of parts on the car was responsible for the
vibration.
with this software will do that
automatically,
but you’re going to need some sort of
the data link connector
interface, and so this one right here
is an ELM 327 interface
I purchased this, I think it is around thirty
dollars off of; I forget, it
was either eBay or
Amazon
and I’ve tested this are tested on
several different brands of vehicles
that we have here in our shops. It works
with
all of them, as far as allowing the NVH
software, and NVH stands for noise
vibration and harshness,
to interface with the ECM, the engine
control module on the car, to retrieve
at a bare minimum engine RPM and
other things also, but you’re going to
need some sort of an interface
but you may have one, you may have one
already, depending on who were you work
and what
scan tools and scan tool software
you have;
that’s one option. Another option
if you work on Toyotas, Toyota calls
this the TechStream light,
and this is made by Drew Technologies,
it’s the Mongoose pro
MFC and this is not
30 bucks this is closer to five hundred
dollars, but it does
everything that you could possibly want
on the Toyota vehicle,
not just communication with the engine,
but every single module,
it allows for reprograming and everything, where
the ELM
pretty much is just ECM
communications, the Mongoose does
a whole lot more, so it it’s certainly
worth
more money, but if you have one of these,
this works,
and with more than just Toyotas. I’ve
tried this on
a General Motors vehicle and other
vehicles that we have here
and works just fine, and that’s because
all these
are supporting the
Society of Automotive Engineers
standard
number J2534 which is the
serial data communication
protocol
over the CAN lines.
If you work at a
General Motors dealership then there’s a
GM
MDI, multiple diagnostic interface
module that will;
it’s a USB to data link connector, it
works just fine.
Also, when there’s a separate kit
from Picoscope just for GM dealers. If
you work in a Honda
or Acura dealership, they use the
modular vehicle communication interface
kit, the MVCI,
and it also works, I’ve tested it
on several vehicles here with the
NVH software and it works
beautifully. What does not work though
to my surprise, is the Ford
VCM, the vehicle communication module,
it does not work with the Picoscope software
and
the Chrysler
the wiTECH scan tool interfaces with the
USB,
the iPod, or not iPod, the wiPOD 2
the miniature,
well let me see, I’ve got the name of it, I forgot
the name of it.
It is the VCI Pod, Chrysler
wiTECH VCI Pod and the Micropod 2.
Neither of those devices
would work with the Picoscope software today.
I don’t know that they
won’t work in the future but they do not
appear to support the J2534
interface, so if you have one of
the
devices i’ve to shown you that works, great
use that, if not, I would recommend one of
these inexpensive
the datalink cable interfaces,
and when you plug this in Windows is
going to have to find
the driver for it, it uses a universal
driver
and it takes a few minutes the very
first time that you install it, for it to
find
the driver software but it it installs
and works
just fine, what
I have not been able to make work
from the same manufacture, chipset
manufacturer: ELM,
is the ELM 327 Bluetooth
interface, it would connect with the
software and then disconnect and then
connect and disconnect, it drove me crazy
wasn’t reliable. There’s one that
uses wifi, it creats wifi hotspot
you hook your laptop to it like it’s the wireless
network;
didn’t work at all. And then there’s the
newer small compact version of the ELM
327
with firmware version 2.1 that
wouldn’t work at all either, and that was
just with the current
the software that we have as a the
data this video here in February of
2015. Maybe in the future
those something work but
personally I prefer a hard wired
connection rather than
then the Wireless
connection, is just more reliable. Okay,
so, we’ve got the Picoscope
oscilloscope, we’ve got some sort of a
data link connector
interface, and a laptop a computer,
and then. like I said you’re also going
to need the
NVH, and once again, NVH is noise
vibration and harshness.
There’s a microphone in here so
we can use it for noise diagnosis;
you try to find where a weird noise, squeak,
rattle, is coming from in a car, you can do
that with this kit,
and I’ll shoot a separate video on noise
diagnosis.
and then the V is vibration diagnosis
which
you’re going to show you today. I’ve got
a car with some actual problems
and I’m gonna show you how this kit
actually works to find the problem
on the car. Harshness is how hard
it’s shaking, so we’ve got this kit
let me open the kit up and show you what
we’ve got inside here.
We have the NVH interface box
which is going to connect to the Picoscope
oscilloscope itself
so we’re going to take this interface
box along with
a cable that comes in the kit and
we’re going to connect the cable to the
interface box
and the cable to, remember,
input B on the the oscilloscope.
Okay, so we’ve got the Picoscope, the
cable, and the NVH interface
this NVH interface then has a connection
on the end here
that allows us to either connect a
microphone
for noise diagnosis or an accelerometer
or vibration sensor for vibration
diagnosis.
So we will demonstrate the the
vibration diagnosis today.
there is a magnetic sensor tip
the comes in the kit I’m just going to
screw that in
to the top other accelerometer here
there’s little metal washer
that keeps the magnet strong, that we will
take off so that we can
attach the magnet to something solid
on the car when we diagnose vibrations.
But this
the cable is is pretty long, this
extension cable that connects the
interface to the Picoscope is really
long, so you’ve got lots of
cable to move the sensor
around the vehicle
it also comes with an extension cable to
make it even longer if necessary.
This extension cable works with
the microphone also, so we can move the
microphone around
on the vehicle for noise diagnosis
like I say will do that in a separate
video okay
Now we’ll take our vibrations sensor, and
it’s got a keyed
connection, so we’ll plug that in, it’s
got a threaded connections, so we will
lightly screw that in.
There’s LED here on the end; that LED
the blinks periodically to indicate that
the interface is powered up and working.
Their is a
battery inside of this module and so
the the entire time that you have this
sensor plugged in,
this battery is going to be slowly
draining.
So when you store the interface box
back in the the storage box you want to
make sure that you disconnect the sensor
from the box or it may run the battery
dead, and there’s just four screws on the
back.
You take it apart and change the battery
them when necessary.
Okay so, let me
get this box out of the way.
Lets just look one more time here
we’ve got the laptop computer,
we’ve got a data link connector
interface that we’re gonna plug into
whatever car
we’re going to diagnose for vibration
diagnosis
We’ve got a USB cable that connects to a
Picoscope
4-channel electrical oscilloscope that
has been
the specially configured so the channel
B will also interface with the Pico
NVH interface box where we can connect
an accelerometer for vibration diagnosis
or a microphone for noise diagnosis.
Now there are some other optional parts
that you can buy
and I’ll show you these you know in
another video that
will allow you to balance an entire
drive line system
on the vehicle, which is a much better
balance than just sending a drive shaft
out to get balanced because you’re
balancing
everything that rotates the same speed
as the drive shaft or propeller shaft
whatever you want to call it. So we’ve got
the
the laptop, we’ve got the
data link connector cable ready to go,
we’ve got the USB cable, the Picoscope
oscilloscope,
the connection cable to the NVH
interface, and then the
vibration sensor with the magnetic tip
the we’ve screwed on it. We are already to go over to the car
and perform some diagnostics. Now on this car
that I’ve got set up, I’ve created some
vibrations and we’ll see which ones
the software is able to pick up and
we will see you if we can find
abnormal vibrations as well as a normal
vibrations,
and I’ll talk about the differences
between those two.
So lets head over to the car. Okay
were over to the car, this is a 2013
the Chevrolet Camaro ZL1
with the LSA supercharged the engine,
a very impressive the car,
and I’ve got some vibrations
purposely set up on this for us to
diagnose
and what i have done here is: I’ve got
the vibration sensor
right here, I’m just going to attach
it
to the radiator support
here for the moment
just for this demonstration on engine
vibrations and then
when we get insider the car we will put
the
the sensor on the seat frame for the
other
types the vibrations. So
lets bring the the laptop in
over here and take a look
at the software.
Okay, the software right here is
Pico diagnostics, so I am going to
double click on that. Down here in the
bottom left
it reads Picoscope 4423 open
successfully
If it can’t find an oscilloscope
you May
want to double check your USB cable
connections
to make sure everything’s okay, but in
this
version of the Picoscope diagnostic
software
a noticed we have five options off to
the side here
within NVH being the one at the bottom
and balancing be in the one in the
middle. The GM software
version that I showed you in episode four
only have balancing and NVH,
it did not have compression test, battery
test, or cylinder balance.
In this video we are just
gonna play with NVH, and like I said
we will
do a separate video on balancing the
propeller shaft, so we’ll go with NVH
and
we’re going to click on “Start a new test”
in this the setup wizard, so click start
a new test, let me zoom in so you can see
the dialog box little better. We’re going to
tell what we want to connect through the
data link connector through diagnostic
a J3524
interface, and I showed you that the
thirty dollar one that I had from
from ELM, the ELM 327, its going to search
for any the data link connector
pass through our interface device that
supports the J2534,
it also look for an ELM 327
chipset in some sort of an
interface a box also. The ELM 327 is a
chip,
people by the chip and make their own
interface
kits with it, so anyway
we are going to
click Next to continue, it’s going to
attempt to
communicate with the ECM through that
ELM USB
cable, but like I said this
just as easily could be the GM MDI
the Honda MVCI, it
could be the Mongoose
the cable from Drew Technologies or
I’m sure there’s others out there also.
Notice it took in a minute, but it says
now Elm 327 version 1.5
connected and it has the VIN number, we just want to double check that’s the right VIN
number which
it is on this car, so we will hit Next,
and by pulling the VIN number it knows
what engine
it has off of the 8th digit, and what
year the car is off the 10th digit.
It doesn’t know the axle ratio where the
transmission gear ratios,
but it can get the engine RPM
based on this type of information.
So we will hit Next he wants to know how many
cylinders it has in the engine? We have
8 on this, Is it an inline engine or a
V-type engine? This is a V-type.
So we’ll hit Next, now they want to know
rear wheel drive, front wheel drive,
all-wheel drive, or four-wheel-drive?
This Camaro is rear wheel drive. they
want to know the
differential gear ratio; you’ll have to
look that up in the service information
or find it some other way, but
the this particular vehicle has a 3.23
gear ratio. On GM vehicles there’s a
three digit code
on what’s called the regular
production option label,
and then you look that up in service
information and it will tell you
will gear ratio has, so
3.23, so we had Next.
It wants to know the size of the tires,
and on this vehicle we have

We have 285/35ZR20,
it doesn’t like the Z, we just leave the R
so we will put 20 right there
We will leave the box clicked for “Use
the same size value for both tires”
so they are the same on this car, so we will hit Next,
The sensor location; we’ve got the engine
compartment option
or passenger compartment. we’re going to
start with the engine compartment
and it goes to the default accelerometer
that came in the kit.
There are other types of accelerometers
or the microphone
available also so I’ll hit Next to
continue.
It tells us to tap on the sensor
to verify that we have a signal and it
does not look like we have
a signal.
Just make sure all the connections are
good,
normally there’s a little green bar
that goes across here
showing signal quality, and it’s not
working at the moment, so let me
disconnect the sensor real quick
plug it back in
there, we are getting a little of movement on the far left
of the bar graph there. Let me
move it again, let’s see if
it gives us a,
yeah there we go, okay
I don’t know what happened, maybe it went to
sleep because I’ve had a plugged in for
a while here preparing, so we’ll just
hit Next
It tells us where to attach the accelerometer,
it tells us that it needs to be in an
upright position on the inside
track at the driver seat which is a
great place to put it if you’re
the going out on a road test and that’s
where I wouldn’t normally always begin
more kinda doing it a little backwards here
starting with the engine
vibration diagnosis. In all the years
I’ve
experience I have diagnosing vibrations
Ive always been able to
pick up the frequency that I wanted the
offer the drivers seat track.
Okay so, we will hit Next
It says you’ve completed the setup process and now
can perform and NVH tests
click here for help diagnosing NVH
faults
and it brings up a help file that
gives you information on the basics of
vibration
and then step by step diagnostic
procedures for
the three different types vibrations the
you can
have on a vehicle, typical types, we have
vehicle speed related vibrations,
of which there are two types of those, we have
tire speed related, and propeller shaft
speed related,
and when I say related I mean anything
spinning the same speed as those.
so as far as tires are concerned we’ve got
the tire, we’ve got the wheel,
the brake drum, the rotor, the axle, the
ring gear, the differential case, the
the side gears, and on, and on,
and on, and the same with
the front tires. For propeller shaft
speed related vibrations we’ve got
the propeller shaft, the pinning gear, the
pinion flange, the
inner bearing races, transmission
transfer case
output shafts
and so on, even internal transmission
pieces.
And then we have an engine speed related
vibrations that we’re going to look at
right now. And engine speed related
vibrations
are vibrations that occur
that go up and down with engine RPM that
have nothing to do with vehicle speed.
So these vibrations most the time can be
duplicated in your stall,
however; sometimes it only occurs under
load when the engine is twisting and
flexing in the motor mounts, transmission
mounts, and so on.
There’s also another type a vibration
related to electric motors
and if you noticed in the the episode 4
on the GM Picoscope a exercise
towards the end of that exercise
when we were measuring vibrations
there was a strange vibration that
I told you to ignore and I realized
today playing around that it was the electric
cooling fan
the spinning at about 5,000 RPM
and so that would come and go. So
there’s an example of a
vibration that
is picked up by the the vibration
sensor that may or may not be a
concern. We actually had the sensor
right
on the the fan shroud area and so
it was normal for that to be picked up
but the fan shroud and the engine and
all that have mounts to dampen that out
so you shouldn’t be able to to feel it
in the passenger compartment.
Okay so there are step-by-step
procedures;
I’ll show you how to access these as we
get going, so we’re just going to hit Finish
and then let me zoom out here you can
see the whole screen.
Okay,
You’re not going to see anything at
the moment
until we tell it to start recording.
So I am going to start recording. This
will record,
according to Picoscope, for 500
seconds.
I’ve only been able to get it to
to playback 50 seconds, but maybe I’m
doing something wrong
But anyway
what it defaults to here; we have
five different options to display
vibrations
The one it defaults to its frequency and
in this graph area here we have
vibration frequency starting at 0 Hertz
or zero shakes per second going clear up to
180 Hertz
180 shakes per second, and then
that’s in the x axis, in the y axis here,
the vertical axis,
we have forces of gravity which
doesn’t have anything do with gravity other
than as a comparison to the force a
gravity.
but its it’s a unit of measurement for
how harsh
the vibration is, and so
the higher these little spikes go
the more severe the vibration is.
Now there’s another way to look at this
that I like and it’s clear over here,
its bar graph. so lets go with bar graph,
and what we have
now is
all these different labels T1, T2, T3,
those are,
T1 is first-order tire speed related
vibration, so that’s one shake per
revolution
the tire, T2 is two shakes per
revolution, T3;
three shakes and so on. E1 is
engine first order so one shake per
revolution of the engine
E4 is four shakes per revolution
at the engine.
And then we have P1 and P2. P1 is
propeller shaft
first-order, so one shape a revolution
other
propeller shaft or driveshaft as
people call it sometimes,
or two shakes per revolution of the
propeller shaft
and it gives us
a bar graph the higher that bar graph
goals the more severe
the vibration is, now there’s a
specification that Picoscope
has given us and that is if it goes
higher than 10
milli-g and we’re at 3, 4, 5 right here
then it’s one that you should for sure
investigate
if you’ve got a customer complaint
of the vibration.
But to put a specification on something
is kinda tough,
really what you want to do is, in my
opinion, is find
the vibration frequency that has the
highest amplitude that the customer is complain of

on your road test, see how high a the
amplitude level is in
in G force here, and then after you have
supposedly fixed it
the way you verify you’ve got it fixed is that
g-force level should be
significantly reduced if not
totally
eliminated. Sometimes you don’t have to
totally eliminate you just reduce it
and the customer will be happy. So
bar graph. Now lets talk about normal
vibrations for a moment
on the engine, on a eight-cylinder engine
we have four
pistons on the powerstroke
where the spark plugs just ignited the
air/fuel mixture and it
forces the piston downward rapidly four
times per revolution of the crankshaft
on eight cylinder
and quite simply you just take the numbers
owners in the engine
and divided by two, and that is the
normal
vibration that you will have have on
that engine.
Now there could be other normal ones
depending on the engine configuration
but this particular one on a V-8
fourth order is normal, first order is
abnormal,
so it’s it’s okay to see a little bit
of it here on the
radiator support, and it’s a quite
low
amount of amplitude, but, let me move it to
the engine and lets watch what that
amplitude level does now.
Find a place to put it here, here’s a
spot.
Alright, let me get the laptop lined up
again with your screen so you can see what’s
going on.
Okay now notice
that we are
we’re off the chart, well, we can
read a numerical value down here, 60-70
milli-gs;
it it’s gone crazy
and that’s because we are on the actual
engine side of the motor mounts, and so
motor mounts, transmission mounts, the
exhaust mounts, body mounts,
are all designed to dampen that frequency,
or dampened the harshness, the H
part in NVH,
down to a level to were it’s acceptable
to the driver.
So if you have bad motor mounts
you can end up having a higher level
of amplitude for normal engine
vibrations
come through, and there’s a lot of other
things that can cause that,
and the help file that comes with the
Picoscope software
lists all those things for you to check.
Now we should never feel that in
the passenger compartment
and if you do then you
you check those things. So that is an
example
of normal engine vibrations verses
the abnormal vibrations
and how well the motor mounts dampen
things out.
Let me move that sensor back to the
radiator support.
Okay its back on the radiator support,
you can see that we’re back down to an
extremely low level of amplitude
and so the mounts are doing what they
should,
and so there’s a couple reasons I
show you this, one is to illustrate the
example of amplitude,
the higher this bar graph goes, the higher, or the more harsh, that vibration
feels on the vehicle. Now
out of all these options for this plane
vibrations I’ll I like the bar graph the
best, I think it’s the
most simple way to look at vibrations.
Okay so now
lets look at the
vibrations that are relative to vehicle
speed and not relative to engine
vibrations,
and to do that i’m going to need to move the
sensor to the seat frame
and then we will put the vehicle in gear
and run it up and see what we get.
Okay I’ve
moved the sensor to the passenger
compartment
and I’ve attached it to the
seat frame rail,
the inner rail is the preferred
place because is more centered on the car,
but I
put it here on the outer rail so you could
see it
more easily, but
there’s the seat frame, and I’ve got the
sensors
stuck their right to it, and so
that gives us a good solid connection
with the chassis the vehicle
right where the driver is sitting in
and that will help us to duplicate the
customer concern
better than if we have the sensor
mounted anywhere else on the entire
vehicle.
And and like I said before I I’ve
never seen
a vibration that I couldn’t pick up the
frequency and identify it
using one of the vibration
analyzers and the previous software,
and I I’m sure this Picoscope
software’s is the same, so
what I’m going to do now is
take the;
I’ve got the vehicle in gear,
we’ve got the propeller shaft spinning,
we’ve got the
tires spinning, this has a
limited slip differential, a clutch
type
one I believe,
two where both rear wheels are spinning
the same speed
always. Now you normal you shouldn’t
try to diagnose vibration problems on a
hoist if they are vehicle speed
related
because it with open differentials,
whether it’s front-wheel-drive, or rear wheel
drive
your tire speeds will not be the same as
if they were
driving down the road. Typically with an
open different so you have one tire
that’s
either totally stopped and the other one
spending twice as fast
or some combination of
anything but equal speed, which can
throw off your
the calculation numbers, and that will
little mess up
the, well it just ruins the
the math, it doesn’t work
for matching if you have a tire speed
related vibration
which is the most common type a
vibration.
Okay so
I’ve got it in gear, I’ve put it in the
manual
mode, and even though this is a
Chevrolet Camaro
this, as I said the software in this
Picoscope NVH kit will work on any vehicle
I’m not using the GM interface module
I am using that
ELM 327 USB module
this could be just as easily be a Ford, or
Chrysler, Toyota,
Honda, it doesn’t matter, the principle is the
same here
front wheel drive, rear wheel drive, differences.
But now
let’s take a look
at the software itself
as we rev this
engine up and
make it create the vibrations
that I have caused, or made some
components have vibrations, and
let’s see if we can diagnose
what the cause is. So i’m on bar graph
mode right now, excuse me, and
i’ve got the tires and propshaft spinning,
i’ve got the engine spinning
I am second gear, I believe, and
I’m just going to bring the vehicle up to a
speed where the vibration
is real obvious to me, I’m not looking for
specific speed
unless the customer says it occurs at a certain
miles per hour, which normally
they would give you some
information like that, let’s take a look
as I rev this up
and see what we get
for different frequencies, so I’m gonna
take us up to…
here is 25 miles an hour right here,
notice you’ve got a little E4, a
tiny bit of E1
little bit of T1 on the tire, and we’re at
about
2500 engine RPM, now let me take it up
to about 3,000 engine RPM, right there
at about 30 miles an hour, and now look
what we have
our engine vibrations are a little bit
higher and that is to be expected, but look at
that T1
that T1 vibration tie amplitude level has
come up, the bar graph is getting a little higher,
notice there is a tiny bit of a P1 there also,
so now let me take an even higher,
here’s
3250 RPM, now look at our primary
vibrations,
and this is that about 35 miles an
hour,
we’ve got a severe T1 vibration
and a pretty bad P1, so we have a tire
first-order vibration
and a propeller shaft first-order
vibration.
and you can see that
with those bar graphs being as high as they
are right there, remember
anything above 10 milli-g
is something that should be corrected as
long as there’s a complaint, so let me
bring it back down
I’m going to hit the spacebar to save
that.
It stopped recording right there
and now I’m going to come up to
the File menu, click File
save, and
I’m just going to put
Camaro, and I could put the make and
model
and all that over here but for this
video, just for quickness,
ZL1
with the P1
and T1 vibration,
and hit OK.
It gives it
a name based on that the date
and time and will stored on our hard drive
for us.
It says it already exists, do we want to
replace it? No, we don’t want to replace
it.
I guess this maybe is not the date and
time
I thought it was 15 is for 2015, 02
is the month, and 26
is the day. Oh, it’s just the date,
doesn’t have the time.
so I’ll at the time; 1:41
There we go,
save, and it’ll save it, and then we
should be able to pull it up and recall
it and we’ll see how long,
how much time in seconds it has
saved.
And that’s something we can save and show
to a customer or to someone that doesn’t,
maybe, doesn’t understand, or believe
what the vibration amplitude was
before the repair
and then after the repair. So let me
turn the engine off here. So
those were the before repair
amplitude levels and
then of course you need to go through
and find what causes those.
We’ve got a p1 vibration
and T1 vibration.
And so how do you find what the cause
those is?
Well, right here on the screen we can
come in
and right there where is says T1, and
right here where is says P1 we can put our
mouse right
their in click. It tells us that
it’s a first-order tire speed related
vibration and tells us a little bit
about that
that it’s caused by something that
is out of round, I’m sorry, first-order
tire speed related vibrations cause
one shake or disturbance per revolution
the tire, click here for more information.
I will click
and then the Vibrate software help file
opens and it takes you through a list of
things that
cause first-order tire speed
related vibrations
and they’re shown in the most likely
cause to the least likely cause.
So a tire or wheel that’s out of round.
Believe it or not you don’t want to just
balance all the tires if you have it the
T1
tire speed related
vibration
because tires can be out of round, they can be
like egg shaped and
I think I said in another video in this
series, if the tire were square
you could still balance it, but as a
flops down the road it would obviously
cause a vibration, so
you don’t worry about balance first, you worry about out of round, and then you do balance,
and then there’s all these other things
that list for you to check,
and it does the same thing for
propeller shaft, and so if we come over
here to P1
click on P1, it tells us
what first-order propeller shaft
vibrations mean
or what defines that,
click here for more information
and it pulls up a context-sensitive
help file
for what can cause first-order propeller shaft speed related
vibrations.
And that context sensitive help file comes up for every type a vibration,
tire speed, engine speed, propeller shaft
speed,
and other speeds, we can do the
pulleys
on the engine. if you thought you had a
belt-driven our gear driven
accessory with a vibration.
Okay, well this is
been kinda bill a lengthy video but
vibration diagnosis is not
guesswork,
it can be very precise, you can
really waste a lot of time if you
don’t have the proper tools and the
proper training and
this is the proper tools the help file
that
comes with this gives you step-by-step
instructions for
diagnosis once you’ve narrowed down
which is the bars on the bar graph,
and it could be more than one, I showed
you two different ones here are on the
same vehicle, a P1 and a T1,
that isn’t very common, normally is just
one
those bars the that will be up there
and its just a step-by-step process
to go through
and diagnose those. So I as I said I
believe the Pico NVH interface;
NVH diagnostic kit,
is a fantastic kit, I think it’s the best
on the market
today and it is expensive but it’s a lot
less expensive than guessing and wasting
your time
and
money at throwing parts on the
vehicle,
and you all probably seen vehicles were
you’ve
wasted way too much time and put
parts on the didn’t make any difference,
and this
software will help you eliminate that
wasted time and eliminate putting parts
on the won’t do any good.
So this has been a demonstration of the
Pico NVH
diagnostic kit. Have a good day!


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