welcome back to steve rob reviews today 2015 chevy cruze 1.8 liter and it's running horrible so this
is this is just a quick overview of a procedure that i do all the time on diagnosing a misfire
and for a lot of people that don't know what a misfire is it's just actually one of one or
more of your spark plugs not actually firing and there's a reason for that majority of the time
it's either a bad spark plug or a bad coil on this particular engine here it's a whole coil pack you
just can't replace one coil you got to replace the whole unit itself so what i'm going to do i'm
going to show you the engine here and i'm going to show you some things that you have to really pay
attention to when you're first taking everything apart so this one here has a code of p0301 which
is a misfire a number one cylinder so what we're going to do is take a look and see what number
one cylinder actually is and point out exactly how you interpret the data from your scan tool and all
you need is a little cheapy scan tool like this you know you don't have to spend a lot of money
we're gonna get started and uh i'll just show you the engine first and how you take some of
the stuff off because a lot of people yeah that's the major part there is how do you take this stuff
apart right so let's get to it right now okay so the first thing i'd like to say is i took this off
here you can see there's an arrow so this actually sat in here you just slide it out like this and it
comes off but how do you actually get this off and you could see that there's a track here and the
corresponding side is just a slot so it just lifts right straight up so when you're thinking about
cylinders yeah it's one two three four don't pay attention to that you have to go by the firing
order and the firing order is one three four two so our misfire is right here so what i'm
gonna do is i'm gonna show you the scan data and then what i'm going to do is take this out
and you need a torx 40 to take this off and then i'm going to show you exactly how you take
this particular piece out here but let's take a look at the scan data first so now you know it's 1
3 4 2 is the corresponding number that you take from your scan data and apply it
to here so this is cylinder number one this is also spark plug number one in the firing order
well here we go right there that's just a simple display of the uh the current code p0301 number
one misfire this vehicle's got just under 100k and what was the symptoms well of course it runs rough
really bad and actually the lights were flickering on the inside of the vehicle
it was running so bad you have the stability track the traction control that
that flashed up on the display center and also the check engine light here it was flashing so
when you see that flashing well you know for sure that you shouldn't be running the vehicle
and you know when that starts flashing you better off turn it off and get it fixed because
if you let it run for too long like that well you can destroy a lot of things especially your
catalytic converter so let's uh let's go under the hood and i'll show you how to take them connectors
off to take this whole coal pack off you take two screws out you have to lift it right up
but first you have to disconnect right in here and this is a safety tab you have to pull i don't know
if i can get the safe pad back yeah pull the safety tab back here and then you grab a hold
of the sides and you can just pull the connector right back so that's all you have to really do
you can figure out how to pull the connector back we're just taking the safety tab off here first
now the whole idea behind this is we know that the misfire is from this cylinder number one
or number one in the firing order so what i'm going to do is i'm going to swap this spark plug
for the furthest one away which is this cylinder and see if the actual fault goes to this cylinder
and if it does then i know it's the bad plug if it stays here then i know we have to replace
the whole coil pack assembly well this is how far i got i got the coil pack out here's the
number one spark plug i'm going to swap it with this one right here and we'll start the vehicle
back up but i just like to mention something if you take a look at this connector here well
of course when you press on the tab to pull the connector back well i'll show you what happened
so here's the connector right here and all you do is just press on it back and uh the
connector is supposed to pull out well you shouldn't have this connector in your hand
and as you can see it's only a little plastic tab going across here so this thing actually broke
first time it broke i guess after five years it gets brittle but uh this safety tab well
i'm just going to leave it just the way it is put it back together and i might jerry rig something
up to make sure that the coil you know wire can't fall off anyway which i doubt it could
but that's something you might run into first time i press on this to pull it back
you can see where you're supposed to press on it right here with these three little slots
and it just falls apart isn't that dandy okay so there you go right there i uh
i erased the original code started it up just for a bit and i'll show you what it looks like
when it starts up but the original coat is back so by swapping the spark plugs did nothing it
is the coil pack itself so i'll just briefly start it up i'm inside my garage here now and
so i can't really run it for long but that's what you could expect to see on your dash as well and
you see there are the lights that are going to be flashing that's what you're going to
see when you see a misfire right there so it looks like it's getting a new coil back
okay here's the moment of truth that light goes out the problem's fixed i'll take you
out underneath the hood and show you how i fix that connector on the coil pack
and i'll explain a couple other things i just kind of ran over
slightly that might be helpful but let's get to it let's start it up
well there you go right there everything's fixed that's just a seat belt warning light
okay so how i fixed that connector was i just went underneath the first post there
and then i brought it up underneath and just used one of these cable ties just to hold it
on you don't have to go gorilla tight on it or anything but that's pretty much it right there and
i don't think that'll ever fall off again well before i take you over to the bench
i just thought i'd let you know that this particular coil pack well there's a lot of
other faults that could happen to your vehicle like you could have one of your connectors here
not making contact or even a mouse or something further downstream has chewed the wire you could
have a mechanical problem with your vehicle in that particular cylinder but overall you know
what most of the time it's the plug or the coil so i'll take you over to the bench here and i
just want to to just go over just like something to take for instance you don't have a scan tool
well what do you do then because there's a lot of people that just don't have a scan tool well
i'll take over the bench and i'll show you how you can pretty much tell which cylinder was misfiring
without a scan tool so here's the four spark plugs and you can definitely see you know one
is different than the other the one on the far left here i mean come on you could definitely tell
that it's not the same as the others so i mean there you go right there that's a telltale sign
right there so another thing i would like to point out is yes i use a torque wrench to torque up the
spark plugs you take them out when they're cold you put them back in when they're cold and this
is a great little tool here you can use a rubber hose but this just fits on the outside of the
spark plug here so when you put it into the spark plug tube itself well you're not just relying on
the grip of your spark plug socket because if it falls down well guess what your spark plug is now
you know probably going to move the gap at the end here might be damaged even so what i did is
i put in these spark plugs here that came with the kit they're not acdelco but i did get the
genuine gm part now i bought these all off amazon and i have nothing to do with amazon
you know but i will tell you something this coil was 141 off of amazon the new one
exactly same replacement and it was 268 at the dealer so for me it was a no-brainer i
don't know why the dealer charges so much more it's the exact same part it's even shipped in
the same shipping box that you would get at the dealer so you know there's a good tip right there
but overall what would i say about doing this job and what kind of a skill level do you have
to have to do something like this you know what for most people just basic hand tools and a
service manual is nice if you got like a hanes or a chilton's manual they're 15 bucks or whatever
you know what it's well worth the time just to buy it and go through it so you can see
you know exactly what the torque level was this one here was 18 foot pounds but when
you're thinking about doing a job like this you have to have a torque wrench absolutely not in my
experience you just don't go crazy tight on it and i've never had a problem but i just prefer to use
a torque wrench do you have to have the scan tool well the scan tool sure does tell you a lot and
it also tells you where there's only one fault or there may be two fault there may be three faults
you never know right so i mean for the price of a scan tool it's very economical to get one a lot
of people are really you know dubious about even plugging it in or understanding how it all works
but at least if you were to take the spark plugs out you could see hey there's something different
with this first one compared to the other three right and that gives you a good general idea and
you know you can just like i did swap it over but at that particular point
well you ain't going to get the truck the spark plug color to change because you swapped it over
right uh i mean that kind of stuff doesn't work but i mean if you just want to try
you know doing this you know without a scan tool it's going to be very difficult i will tell you
so i mean what's a scan tool like this word maybe 40 bucks 50 bucks that's about it how much it cost
you to take this vehicle to your local garage they're going to charge you 150 bucks just to
look at it more likely i mean the whole call pack was 141 dollars so i mean this is probably worth
the investment just to see what's wrong with it and in my situation it was a simple misfire
i just needed a new call pack and you know i was very surprised though that uh
that just first time this has ever been taken off and it snaps i mean you could see that the plastic
on it you know it's like a small little you know thin wedge of plastic that you know that this is
supposed to pivot on so it locks in and all you have is this little safety tab at the end and this
lock here you know and that lock guys i'm saying it's pretty cheesy you know but how often are
these things supposed to be taken off and on while generally you know a lot of times a coil pack is
man it's meant to work for the life of the vehicle so sometimes these things happen so thanks for
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and watch some more well interesting videos on unique thing unique things that i do
cheers
you