hello, my name is john kelly and this isthe weberauto youtube channel. today i am going to show you how to use the new nvhsmartphone and tablet app to diagnose vibrations on vehicles. i have a previousvideo where i showed you how to go on a road test and determine what type ofvibration the vehicle has, and there are basically, there are three types, orgroups, of vibrations that a vehicle can have: one of them is tire speed relatedvibrations, which is everything that spins the same speed as the tires ofwhich there is a lot of things that do that. another one is drive shaft speedrelated vibrations, driveshaft or propeller shaft, same thing, on rear-wheeldrive and four-wheel-drive vehicles. and
then we also have the third group isengine speed related vibrations, and i will show you how to diagnose those alsousing this app, right here in your stall of your shop, but you should have firstgone on a vehicle road test, and like i said, there is a separate video i haveproduced that shows had to road test with the new nvh app. so i'm going to startwith engine speed related vibrations, i have got a 2015 ford explorer right here and i am going to show you what is normal on engine vibrations, and what would beabnormal, and how to tell if the normal vibrations that all engines have arebeing transferred into the passenger compartment to where the driver of thevehicle might be feeling it. so to do
that i am going to use an optional, youdo not have to have this, but it's optional, it is a bluetooth data linkconnector adapter. it is part number bt1a from gopoint technology, andtheir website is gopointtech.com thats gopointtech.com, and you canpurchase the bt1a bluetooth data link adapter, this one works with appleand with android devices, and i said we will have an android version of thislater this summer, but what this bluetooth interface does is it allows usto just plug into the vehicle, communicate with the engine controlmodule, and get the exact engine rpm and if you are diagnosing an engine speedrelated vibration, if that is what you
determined you had on your vehicle roadtest, then i would recommend that you get one of these. current nvh app customers,there is a discount code in the app where you can get a discount off thecost of one of these off the website. so, we are going we are going to plug this in now and start the engine and just let it idle and we will take a look at a fewthings about normal engine vibrations alright, with the app of course, we haveto tell the app what vehicle we are diagnosing, and so i'm going to select"pick my vehicle" to pick your vehicle in the app this is a ford, so i will scroll down to ford, 2015, explorer, and we will add more modelyears, we are adding more model years and
more vehicles every week to this app, butthis is an all-wheel drive, 3.5 liter engine, so that is the very top optionhere, and the app already knows this is a 6-cylinder engine, it already knowswhat the front axle gear ratio is, what the rear axle gear ratio is, this is acrossover all-wheel drive vehicle, the only thing it does not know is whatsize tires are currently on this vehicle so we have to punch in the tire size,these have a 255 50 r 20 tire, and once w ha've punched in that tire size all wehave to do is hit "start" and it takes us to the "vehicle view" screen. i want you tonotice that with me just sitting here holding the smartphone there are no parts glowing red on the vehicle
view screen, and if you recall from theprevious two videos i have done on this app whenever they app detects a vibrationthose parts will glow red on the screen so obviously i am not vibrating, i am goingto set this on the radiator support of the vehicle here and see if it detectsany vibrations, and if it detects any vibrations, it will glow red,now there is a sensitivity level adjustment in the settings, by defaultwe have got hurt on a medium sensitivity level and you can turn that up or turnit down. now notice, of course, it is not giving us, it is not picking up any vibrations at all nothing is glowing red, but watch whathappens when i set it on the engine,
by the way, i have a cord connected to theiphone so that i can record the screen as we go here, but i want you to noticeas soon as i set it on the engine, on the engine cover, the engine starts glowingred in the nvh app, and that means that it is detecting an engine speed relatedvibration. now there are several different types ofengine speed related vibrations, and this app gives us three different ways toview which type of vibration we have, so we are looking a "vehicle view" first,which just tells us you have an engine speed vibration, the next item is the"live graph" so on the bottom center of the screen, if we click the "live graph"icon, now it will show us a bar graph of
amplitude levels for the different typesof vibrations that are on this vehicle notice the e3, engine 3, enginethird-order vibration, that means there are three shakes per revolution of thecrankshaft, this is a v-6 engines, so on a v-6 engine there are three pistons onthe powerstroke per revolution of the crankshaft, and it's absolutely normal onan engine to have, on a v-6 engine, to have three shakes per revolution, thosepulses from the power stroke of the engine, but if i bring that smart phoneback over here to the radiator support it is gone, now why is it gone? well it isgone because the engine motor mounts, the transmission mounts, the exhaust mounts,the body mounts, all of the mounts are
doing their job, they're they areresponding as they should to dampen the amplitude levels of thosenormal engine vibrations. if you ever had a vibration that did not change when youwent from the engine to a fender, or radiator support, or the driver's seat,the steering wheel, the floor, the dash, then that means that there is a transferpath issue between the engine and wherever the vibration is being detectedor felt by the driver of the vehicle so, that is that's a pretty cool way ofisolating whether or not you have got bad motor mounts, transmission mounts, exhaust mounts, etc. now there's anotherview, if i set this back on the engine,
we can go to the "live data" tab, in the"live data" tab will give us the vibration frequencies or rpm, right now theapp in the rpm mode, rather than hertz (hz) or shakes per second, so this is givinga shake per minute in it, and it color codes anything, anything that, any of thenumbers that are green there are engine speed related, and noticing gives us ourengine speed, our vehicle speed, our tire rpm, and in the results down below, we aregetting a third order tire speed, i am sorry, a third order engine speedrelated vibration, which is exactly what we thought we would have. okay, now, lora, step on the brake and put it in reverse. with a vehicle under a load sometimesyou'll get additional vibrations or even
more amplitude from an existingvibration, lets see if that changes anything here, nope, we still the third, occasionally you'll see a second order engine vibration, v-6 engines also have a second ordervibration that might be load sensitive or torque sensitive. alrightlet us go to a "bar graph", there is our engine third, a tiny bit of an engine one every once ina while, and then back to our vehicle view screen. alright put it back in park. now i have had some comments of wanting to know how accurate this app is as far asmeasuring frequencies. so i am going to
switch, i am going into thesettings by clicking on the gear icon and if we go down to units ofmeasurement, click on vibration frequency, and change from rpm to hz, and we go back, let us now look at live data. we are getting approximately 29.7 hz 30hz vibration as this engines shakes three times per revolution of thecrankshaft, well i have brought along a resonant reed tachometer, this is areally old school vibration analyzer, and all it does is shows us the vibrationfrequencies that it is detecting, and how hard the little reed shakes up and down is the amplitude level, so i want you to notice that it is vibrating, and let me zoom incloser here,
scoot everything over so i want you see the reed, right hereat 30 hz, is shaking really bad, so this old-school vibration analyzer,or resonant reed tachometer is telling us that we have a 30 hz vibration,obviously you can see on the nvh app screen that it is picking up a 29.7 hzvibration also, when i had it laying here but its self, without me touching it,notice we have a little bit of a 20 hz vibration there also, that is coming andgoing, and you'll notice on the app that occasionally we get a second orderengine vibration coming in, and 20 hz would match second order vibration,because look at our engine speed
right now, engine speed is 10 hz, so20 hz would be two shakes per revolution, 30 hz would be threeshakes the revolution, so that is a verification of the accuracyof the app and these sensors inside of the smartphone. alright this is on a v-6engine and the next one i want to show you is the same thing but on afour-cylinder engine, so we will pause right here and pick up on a four cylinder. okay we've got a fourcylinder 2007 dodge caliber right here a four-cylinder engine also have normalvibrations, but those vibrations are only going to be two shakes per revolutionsince there are only two cylinders on the powerstroke per revolution of a fourcylinder. so if i set the app, the
phone with the app running, on the engine,we should pick up an engine vibration, so there it is glowing red, if we switch tothe bar graph we should have a second order engine, the e2, notice the e2 iscertainly there, if we move the phone to the radiator support, notice it is either gone, or it is there,but notice the amplitude level, the height of the bar graph is much muchsmaller, so four-cylinder engines are a little more shaky, some of them are, than six cylinders or eight cylinder engines. this could have a transfer path problem to where amotor mount, transmission mount, exhaust mount, etcetera, is transferring some ofthose normal engine vibrations into the
passenger compartment. if we go to "livedata" view, we can see the frequencies and the amplitude levels, noyice the amplitude levels are just extremely low. our engine speed right now is around 14 hz, wejust started it so it is slowly warming up, if i switch that back to rpm, 854 rpm notice on the "live vehicle" view it is just barely pick up a vibration, so this this caliber has some normal engine vibrations thatare being transferred into the radiator support, which means they can also betransferred into the passenger compartment, so if you put this app in onthe dash, or the floors, or the steering wheel and
you pick up this same normal engine vibration, then something is wrong, gasoline engine vehicles should not havethat happening, now diesels, on the other hand, you are always gonna feel a dieselshaking, however, the amplitude level should be greatly reduced, so if we lookat this amplitude level, we are at 0.03 here on the radiator support,if we put a right on the engine itself, it goes way up, 0.6, 0.7, 0.8, 0.9 1.0, a really high amplitude level, so we are getting asignificant decrease in the amplitude level as we go to the radiator support, sothe motor mounts, trans mounts, exhaust mounts, they are doing some of their job,but still somewhere something is
allowing that those engine vibrations tobe transferred, and the help file has a big list of things that can cause thesenormal engine vibrations to be transferred, it is not just motor mounts andso on. alright now, we are as you can see lookingat the vehicle view screen, we are using the bluetooth adapter on this to readengine rpm, but let me show you how this can still work without the bluetoothadapter, if i go into settings and turn off the bluetooth data link adapter, andafter i turn off the estimated engine rpm, if i go back to our screen here, and we go to the livegraph or the the live data screen we
have the ability to manually inputengine rpm. there is this slider right here, so notice as i move the slider allover to the right it goes clear up to 3,000 rpm, and as low as 400, andyou can change the minimum and maximum values in the in the settings, but wewere at about 700 or so rpm on the tachometer, let us set that on there,notice now, telling the app that we are at 700 rpm, we are still picking up thatsame vibration on the bar graph, if we go to the vehicle view screen we are stillpicking up the same vibration. the only difference here is now we hadto manually tell the app what the engine rpm is rather than read it automaticallythrough the bluetooth data link
connector, so that's a cool feature,i said you don't have to have the bluetooth connector, but it suremakes it easier for engine speed related vibrations only, will have no impact atall on driveshaft speed related vibrations, or tire speed relatedvibrations, so here is a normal four-cylinder engine vibration, twoshakes per revolution, high amplitude level, we move it over to the radiatorsupport or somewhere inside the passenger compartment, and the vibration is either totally gone, or significantlyreduced, that is what we are looking for. alright now, let us take a look at a v-8engine. okay, our next vehicle is a v-8, so we
looked at a 6-cylinder, a v-6, a 4-cylinder, and now we are at a v-8 we have a 2015 gmc sierra pickup truckwith 6.2 liter engine, it is sitting here idling at about 600 rpm, as you can see with blue words for engine speed, we are using the bluetooth datalink connection, andthis is a four-wheel-drive vehicle, so has a different vehicle powertrain there,if i set this on the engine as we have done on the 4-cylinder in the6-cylinder, now notice the engine is glowing red in the nvh app indicating thatthere is some sort of engine vibration. the app will automatically tell us, if wetell it to record the vibrational, tell us what type of an engine vibration itis, or we can go into the bar graph, the
live graph, and notice it says it is an e4 vibration, engine fourth order, so this is an 8-cylinder engine, so it has4 cylinders, basically just half the numbers, four cylinders perrevolution on the powerstroke, notice it is a fairly low amplitude vibration, ifwe go to live data, we can see it tells us fourth-order engine vibration at apretty low amplitude level, alright now, as we move this out to the radiator support let us go back to our vehicle view,notice the engine is not by glowing red indicating a vibration on the radiatorsupport or anywhere else, if we put it on the vehicle, there is nothing on the thebar graph, and there's nothing in live
data with a three-axis inputs from theinternal sensor, if we go to turn off the bluetooth datalink and turn off theestimated engine rpm, and we set our engine speed with our slider atapproximately 600 rpm, now we moved back over to the engine, it may have slowed down just a little bit, let me move the rpm down, there we go, so a fourth-orderengine showing up, if we go to the bar graph, fourth order engine, and you and if we go to our vehicle view screen, the engine is vibrating, all without a bluetooth input,so we can use bluetooth or the manual rpm. slider to tell the app the enginerpm, and then it does the calculations based on the type of engine, and thenumber of cylinders, as to what is normal,
and ther i's a whole bunch more to that,and as i said there is a help file included in the app that tells you allabout engine vibrations, which ones are normal, which ones are abnormal, why they are abnormal, and what to do about diagnosing and repairing those .okay, that is a demonstration of diagnosingengine speed related vibrations as far as do they exist on the engine?of course they do, and do they exist outside of the engine? which normallythey should not. as i said diesels, a lot of time will, but the amplitudelevel should be significantly lower. alright, thank you for watching.
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