Crank No Start That No One Could Fix SBQM Free Video! 

I'll certainly agree with Matt that feeling never goes away, solving a complex problem than moving on to the next.

as a 25 years auto tech i can tell you we learn everyday! if you are willing to!!!

You used your head, applied your knowledge, and fixed the problem. Excellent, sir.

Your classes have taught me a lot. I figured bad ground before you called it. Thank you for all you teach

Great video you remind me of Scanner Danner.. I've been a mechanic for 20 years, & I agree always start with power and grounds,, btw on Chevys is common to have problems with grounds especially with wiring traveling through parts that vibrate or under exhaust manifolds or close to them. My hat goes off to you sir for calling yourself a do it yourselfer, shows humbleness.👍

There is a reason why I subscribed to your channel, your methodology of fault finding is top notch....all the way from South Africa 🇿🇦

Thought provoking intelligent content- delivered in a no fluff no nonsense manner. Logic applied over and over again. Thank you for sharing.

That was beautiful! When it comes to anything electrical, I'm dumber than a box of rocks. But with you, there is something about you that makes it so clear and understanding.

I knew the problem as soon as I saw the title. Very common issue. Any well versed technician such as yourself should find this issue every time. Good job and great video!

My family buys old (> 20 years old) cars and I ALWAYS clean all ground straps I find as a week 1 checkout. . This is why. GREAT VIDEO. Loved how you came to the problem root cause..

Love your logical, rational approach to problem solving. Excellent job!

Love your videos. I learn so much from your videos

Yes solving a problem can give you much satisfaction and save you money too. Thanks to you I've taken up your tried and tested advise to know how the system works otherwise you do not have an understanding on what you are working on. Over here in Australia I've found a lot of mechanics not interested in working on my 1999 Z28 Camaro but with your video's I have been able to solve most of the issues encounted. Thank you your friend in Australia. Graeme Redman

You deserve the best technicians award in the USA

I'm here Schro! Show me!

Great work Matt. Thanks so much for another excellent diagnosis.

Thank you for taking the time to methodically teach us, as you always do.

Great video great job as usual 👊🏻 I remember as a Chevrolet goodwrench technician back in the 70s 80s living in the rust belt those grounds were always a problem. But I never thought that was the problem on this one looks are deceiving . 👊🏻

You are an amazing teacher and diagnostician! You fix cars by THINKING! Thank you thank you thank you for sharing!!!

Fantastic work Matt! 👏👏👏 My initial thought was wiring because you said intermittent but I still would have followed your usual method because it really does help give direction 👍

I've been binge watching your videos and am learning so much, so fast, it's kinda mind blowing. I've been using a DVOM, a knockoff power probe, and the XTool A30D scanner (same as a D7, but with BT and fewer special functions) and practice with it on my 2006 Matrix with 209k miles.

Thanks for another interesting video. Quite coincidentally, this is the second video in a couple of days I've seen on the same subject. South Main Autos channel had a customer asking for a second opinion on whether he really needed to spend the $4000 being asked the manufacturer's main stealer to replace his entire wiring loom. After diagnostic investigation, he too just needed to replace a corroded earth strap on the underside of the engine.

I have watched a couple of your videos and not only learned a few things but also entertained. Thank you

Great video, and your ignition video is 1 off the best I’ve ever seen really nice explanation , and the most important think is the way you explain, it is so clear and understanding , you do put 100% effort to make sure others understand.

Being a tech brings the money in. I do enjoy the characters I work with and landrover/Jaguar sends me many miles away from home on courses to learn the product. This is easily as good as the courses and I love watching from the comfort of my armchair. He talks perfectly to prompt your own mind thoughts. I love it

I love those kinds of challenges myself. There is a very good friend of mine who is a factory trained technician with decades of experience and he told me he rarely ever sees a sensor failure. According to him the vast majority of the time it is a wiring issue. Case in point. Thank you for your amazing content.

Great diagnostic skills ... Yes .. Your video's are very helpful. Just found your link recently and glad I did ... 👍.. Thank you for what you do.

Very comprehensive analysis of the possibly causes of the issue. THANK YOU.

An absolutely great lesson. Thanks

I haven't had any problems with grounding either...but you really add to my knowledge in understanding diagnostic problems. Thank you, teacher

Thank you so much. I'm checking the ground on my 99 gmc 5.7. The way you explained this is 2nd to none. Everett Garcia Wichita Kansas USA

Nice hoodie Matt! Thanks for the shout out. I bet the Pico comes out on this video. Now back to the video.

At the very beginning of the video when you stated the shop had checked and replaced the cam and crank sensors with no luck, I was thinking in my mind you were going to discover a bent or damaged tone wheel, but that thought quickly dissipated when you showed the count and speed. I was not thinking a missing ground. Great information! Love your approach to troubleshooting.

Thank You Math, for post this video from your paid channel . Heats off

Man, I truly appreciate you for making this video.

Great diagnostic and love learning from you

You have the rare ability to explain complexity in a way that makes sense and is easy to understand. You would also make for a very good lecturer at a university....even just a few hours a week would benefit so many people.

Absolutely the most in depth video we have seen for problem solving a vehicle. We are definitely going to check our ground wires and see if our vehicle will start. Definitely got us as new subscribers. GREAT JOB!!!

yes,...it is always helpful and fun to learn from you with your knowledge and your sense of humor thank you very much for taking the time to make things easier...

Excellent diagnosis. It seems many underestimate or overlook grounds. Your methodical approach is appreciated. Thank you

Great video. GM cars in the rust belt are known for electrical gremlins caused by bad grounds and grounding straps.

Because you helped the poor with their auto repair I thumbs up every video you publish. God bless you. 👍 and I’ll subscribe to your pay content.

Great demonstration and verbal communication. I’m 74, shade tree type, struggling to keep up with how stuff works. I’m a new subscriber. I also view South Main Auto and Rust belt Auto among a select view. Thanks Schrödinger Box!! I’m a builder/contractor so mine is a much simpler world . Dave in Omaha

Thank you, amazing video, you are a great teacher 👏

Huh! I was wrong! no Pico. But to diagnose with basic tools is awesome! It was the hoodie you were wearing that helped you diagnose this!

Thoroughly enjoyed that, great explanation.

The Diagnosis Captain does it again.Well done.I now have a new direction of ingaugment to go..Thanks for your videos, worth every dime. Kalamazoo, Michigan

From earlier on in the video my mind was screaming, "It's a bad ground!" Not just a gut feel, it was more that when you saw the injector signal was firing, and the test light clip on the positive terminal and no test light when you touched the ground circuit wiring, the jig was up. None the less, what a brilliant process, even if you did go to a few more tested areas than "needed." I am glad you did take a longer path to get to your end point, as it gave me a chance to learn more about that GM circuitry. My strength is more in the First Generation Mustangs Shelbys (1966 - 1973), and with Ford systems from the 70s and 80s back when I was working as a Ford tech in SoCal. I can tell you this for sure, your wiring diagrams are superior to the older Ford schematics I had (and still have) to work with, It was not until 1972 that we really began to see fairly decent wiring schematics, and 1973 brought us some even more decent diagrams,. Yet, the wiring schematics you showed are truly superior to the kind of detail I have from my schematics sources (all Ford publications). Anyway, I am a new viewer of your videos. I look forward to seeing more. And, I understand that "rush" when a hard to diagnose problem is finally tracked down and corrected. There was hardly anything more satisfying to me back in the day than figuring out a problem that had gone to so many other technicians, and even other dealerships, before I finally had the problem car come to me. Often the really obscure issues turned out to be ground related. I always enjoyed that logical challenge found in where I chose to begin my diagnostic approach, and why I then chose to go to one "next step" to check as opposed to another one. The logical diagnostic approach I learned in the auto industry served me very well when I went over to the computer industry. I loved solving programming and circuitry issues by applying logic. Now retired, I spend a lot of time sharing things I know about diagnosing and repairing First Generation Mustangs and Shelbys, which are applicable to all older Fords and even other makes. My RU-vid channel has feeble content in comparison to what you have, so far. But, considering my narrow focus I am pleased so many folks have found it to be useful. Anyway, I get why you are sharing your videos, and appreciate your sharing back to the industry we love so much. An aside, I also appreciate when you leave in the goofs and erroneous.needless side trips you take in your diagnostic approach. It lets me get a better feel for where your thinking is. And, it lets me know that indeed it is okay to take a needless side path during a diagnostic approach. Some of my more powerful insights have come from taking needless side trips, where I have a happy discovery I can use at some other time. Anyway, Kudos!

That was a great case, I like the way you took us along to follow your thought process. I was a little puzzled by the wiring diagram, because we don't see all of the electronics there. The wiring diagram notwithstanding, it looks like grounding of the primary side is separate from the PCM, triggered by a simple square wave positive input along the signal wire. That would reduce the chance of inductive voltage spikes reflecting back to the PCM.

Nice sweat shirt. Mike is a great guy. I smiled when it started. Following a path of solid diagnostics wins every time. Great video Matt.

Mate, I am non technician but also have learned so much from you. Thanks.

Spectacular job Matt, good find as well. I had a couple experiences like that as well with my scope on a rope too. Someone a while back spent hours with a buddy trying to figure out why his 89 Chevy truck wasn't starting, they took out the fuel pump and half the top side of the engine apart. Truck still didn't start and they spent a good 6+ hours on it and scratching their heads, like why isn't it starting. The guy calls on me to check it out, go to try and start it, no start, look at the dash, no check engine light, pull out the trusty test light look for ECM fuse, blown fuse. They get a new fuse and put it in, starts right up, told them it may blow again depending on what happened to blow it the first time, but started it up a few more times and let it run and it didn't blow the fuse again. Spent under 10 minutes figuring it out, where the guy and his friend spent over 6 hours and half the truck apart trying to figure out what was wrong. Its thanks to many people like yourself on here that taught others like myself what to do, where to look and stuff. Great job!

Stating the obvious, at 10:00, my brain was screaming "You need to check the ground!". That's something I learned back in the late 70's with the advent of computer controlled fuel and ignition. Because some of the manufacturers attached ground wires in stooooopid places like thermostat housing bolts. But, good job. I'm surprised someone didn't catch it before it came to you.

How easy it is to overlook the basics. Seems like whoever looked at it before you could not see the forest because of all the trees. Good no nonsense common sense diag there, thanks for sharing

This was a great video! I appreciate the detail you go into, it provokes a great amount of thought with revealing connections so that in turn, I could figure out that I'm having back emf issues with my 73 Mopar 360 causing the plugs not to spark and am missing an engine to chasis ground on the tranny end of the engine!!! I think you just solved me a whole number of intermittent electrical issues I've been having! Thank you!

I scored very high on the ASVAB test so I was fortunate enough to be trained in aeronautical electrical and mechanical troubleshooting it’s a skill not easily learned but very easy forgotten when not used. This video is extremely knowledgeable information for anyone learning how modern automotive and equipment work.

Good clip. well done. Eric O had a similar case over on South Main Auto a month or so ago. turned out to be the ground strap between the motor and the firewall completely corroded away. BTY that connector is a called a ring connector, and that one is am “open barrel” design crimp. They take a special die to crimp, but they are better than the barrel type crimp electrically because they have more surface area between the crimp surface and the wire, reducing resistance of the crimp.

I have the exact same problem with my 2001 Tahoe. So I will be checking the grounds. Thank you for your videos

Pre supposing is something we all fall for. Great video.

Nice find. I also love being able to fix problems that multiple others were unable to find. Keep it simple.

Great video! I read (see bottom) that the Low Reference on those ignition coils was an ECM sourced ground which is a dedicated ground for the coil electronics. The chassis ground is meant to supply a ground for the actual coil windings, but can supply the coil electronics too if the Low Ref is down. This system contrasts with Toyota's 4 wire ignition coil where the fourth wire is the ignition confirmation signal (IGF) telling the ECM that the coil fired. Source: There's a PDF titled "Coil on plug ignition - the wired differences" by Matt Dixon which explains this and more. A quick internet search will show this PDF in its result.

Thank you senior,you have helped me solve very many problems.❤

Thank you so much! Having the same intermitten issue with a 99 Dakota. I Have replaced fuel pump, sensors, & key electrics ..now I will look for a bad ground!

Hey Matt, love your work mate. I don't believe GM use the brown wire as a confirmation signal like Toyota etc. The brown wire in this design is a common low reference/ground internal to the PCM, shared by each coil igniter transistor, effectively it's a constant path to ground for all of the primary coil windings. The open ground you were chasing is of course the main ground for the secondary coil windings. However, the PCM may still be capable of monitoring this common primary/transistor ground for coil current/over current purposes, and maybe to detect misfires etc.👍

You are a smart mechanic. Awesome diagnosis

The Disgruntled Mechanic-subscribed !

Great logic and clarity, thanks for another great video.

Man you’re amazing at what you do u make it look so easy and the way you explain things is at another level man ! God bless you and thank you!

I use to work with a guy that had a IQ off the Chart, he had Total Recall on everything he read, could resite a Dictionary and carve a Gun stock from a 2x6. This guy could make a couple checks on your engine and tell you what was wrong. I had a recently overhauled engine in my car-one night when we got off from work at 12 midnight, temp/ about 10 degrees, my car would not start, only turn over, he instantly told me that it had jumped Time, I told him that it was just overhauled several months ago-he said well they didn't replace the Timing Chain so he just advanced the plug wires on distributor and engine fired up as it should. He said now go back to the guy that overhauled your engine and tell /ask him why he didn't replace Timing Chain, of course guy denied that he left old chain on my car...

You know how you can have several teachers that all teach math but you can't pass some teacher's class but there's that one. That's you! It's taught that way. I love to see your videos.

Thanks for the information. I've literally been dealing with the same type of trouble with my 08 Tahoe and now I'm going to take a look amd i hope i am dealing with the same problem. I'll come back and let you know how it goes.

Thx very much for this..I heard "intermittent" at first...that clue made sense as well...now back to my son's 2008 Altima with a new alternator that is not charging the battery...wonderful...

Thank you for taking your time to educate me. I found you a good teacher, a vary human one . Thanks again sir .

There is some deep fixing knowledge there! Thank you

Im into the same issue, crank but hard starting at cold start. thank you for this content and i will try this as reference.

You are amazing brother..... you have one heck of a way with teaching people. Thank you for all of your help and guidance!!!

Great work and video, that’s about the best way to do it! I’m going to test that ground early on if come across this type of issues! Thanks! 🙏

Thanx! I had a no spark issue but ground ohm test was good. I checked my G102 anyway and sure enough it fell off with little effort. Corroded. It was dropping out soon as I cranked it, weak ground. Ran new ground and all good. Thanks for this. It was making me nuts

That was awesome. My Challenger cutout i pulled over and the starter was still turning over. I swapped a couple relays. Didn't help. But also when I let off the key fob starter still turning over. It's been in the shop for four days. Still haven't heard anything but it's got gremlins lol. I'm retired plant electrician. Electronics degree but that was first time I saw the explanation of electronic ecm diagram and grnd. Diagrams. It makes me want to take a class. Thnks

great diagnosis!! The ground wire like that is very common on GM vehicles. Merci

Men I have learn so much from this guy and I always try to explain to my friends how this things works and how they function your the best men

great job. i just went thru a full-on diagnosis (crank-->no start) where current was interrupted and there are so many possible things it coud be. Mine was an older car with a ripped out alarm system and many cut wires. Ultimately it turned out to be an EFI relay that worked, but did not transfer current from pin 87 to 30 and replacing the relay brrought back the check engine light, which did not light up with key on. So solved. interesting and well done video.

Great to share in Matt's total chuffedness - I always enjoy a happy ending!

Wow... I have a 1995 Volvo 850 with this crank no start issue... I think I will follow your set of steps in the diagnostic, that was pretty incredible.

Such an awesome video. Shows that other areas can cause problems thatcwere never thought about. Also some ignition systems are hot at all times, and the ground is turned off/on to fire coils and injectors as needed.

thanks for options you came up with some people wont share thank you

Awesome,I really appreciate that you shared this,it was really informative

Very impressive work and very well executed.

Just want to say thank you. I have a truck in the shop and it ran when it came in. I replaced the oil cooler lines on it. I went to start the truck and it was missing really bad. turn the truck off and would not start again. I did the same thing the other tech you talked about. I never thought about the ground. I bumped into your video late on a Friday. Just got in on monday morning and quick checked the injector pulse. It was working. checked the ground on the coils and there was nothing. Thanks for the help. I was really lost on this one.

Great explanation, don't forget your grounds!!

LOVE the videos. I’m not trained at all, but I do all of my own work until it gets to the really complicated or sensitive replacements, and these videos are insanely helpful. Side note, at least half of the time while you’re talking, your voice sounds to me like crispin glover 😅

Nice video. I was expecting you to check grounds after checking the power and was surprised when you didn't. I just subscribed to your channel so that I can see all of your info and videos.

You always have great content. I need to subscribe to your premium channel so when you refer to the content I can watch and understand... For the price of a gallon of gas (well maybe not), even if I only chime in a few times a month it's still a win... On this diagnosis, Powers & grounds. A lot of times that's one of your first tests. Thanks Matt!

This is generally cause most technicians think in terms of 12v plus, ignoring ground issues or get lost thinking obout sensors, your aproach is more efficient i loved this video, i work audio systems and a client mentioned a problem with his engine, it turns out another mechanic forgot to reconnect the physical batery ground so the car was taking ground though the engine block wow! i just recconected it and voila! the engine problem went away when other 3 shops couldn't find the problem

i yelled at the screen when you checked for 12v input and skipped streight to signal checking lol great video my brother

Great Video !! Grounds are important . Thank you Sir .

You are a very good teacher...!!! Thank You..!!

That was SOOO gratifying... Good job bro!

Common sense with a touch of brilliance

Very impressive diagnosis...😊