Hey buddy,. I have a crazy story for you,. Many years ago,. In about 2008 My friends son had a 1996 Chevy Corsica that had that same 3100 engine in it. And he had asked me to tune it up for him, he had said that it was running rough for about the past couple of weeks prior to bringing it over for the tune up, but it was still running and driving him to school and work every day. And he drove it to my house to have me tune it up. When I removed the two rear spark plugs I seen that they were soaked with fuel, so I tested the ignition coils and I didn't find anything wrong with them,. So I did a compression test and discovered that was zero compression on both rear cylinders . So after pulling the valve covers and further inspection I come to the conclusion that the camshaft was actually broken in half. And after a bit of research I found out that the camshafts in those engines are hollow and are made of very thin metal. I still to this day find it mind boggling that engine even ran,

That is one classy russian haircut there Ivan 😀 Great video as always

@ricanderson5717

Жыл бұрын

At least he hasn't pulled it all out because of crazy problems like this...

@ToyotatechDK

Жыл бұрын

@@ricanderson5717 very true

~5 min in you solved it but its not a normal failure so you correctly continued. That's an impressive use of the pico scope to monitor cylinder pressure! Would have been fun to see the oil pump internals or what was left of them.

Ivan! This was a wild one. Very good diagnosis in the end. By using deduction you used real live data - the transducer doesn't lie! This is one of the reasons I love your channel so much. You don't sleep until you have figured out the solution to the puzzle. Keep up the awesome content! I'll be watching (and learning) right along with you! You have the most unique case studies on the Tube! Thanks for sharing.

Interesting.. I don't know how you do what you do with the customer standing over you, watching your every move and listening to you talking to yourself and us.. Thanks!

Crazy diagnosis Ivan. Would love to have video of the engine with the valve cover removed to actually see the rocker action. Thanks for sharing.

Cool case study! Putting it all together at the end was super insightful. Common or not, the question is, can we use the data and understand the layout of the system and come up with a concrete answer!? Ivan says, yes we can! Lol! Nice one, Ivan!

Definitely an interesting case study Ivan. New cars aren't the only ones that give us a challenge. Thanks!

@grabasandwich

Жыл бұрын

The thing about older cars is that the common failure modes have been well known for so long, but eventually seem to fade into obscurity unless you go digging into things like message forums. Parts cannon repairs should be illegal lol.

That was awesome, it shows your professionalism, not given up until you really find what’s wrong the problem. And I learn more about scopes! I hope soon to get my Pico Scope.

Awesome diag Ivan, in 33 years I've learned that when it's not possible some way shape or form it ends up possible. Keep up the great work.

I too own a crazy Buick century and I've used it to learn about car repair with the help of your helpful videos and even a follow up on video. Thanks for all the knowledge.

A little bizarre, certainly not expected, but aligns with the symptoms. Dissecting the diagnostic readouts is smart: Not only interesting but adds insight into this experience. Another 'good one' .

so here's what I say to myself when I read the waveforms I capture..."this waveform is correct.... my INTERPRETATION is the thing that isn't correct".. the data doesn't lie... nice job Ivan - I wouldn't have been able to sleep until I got my head around that one if it were in my shop!!

Never a good sign to find shavings clinging to a sensor's magnet. That cranking sound... eew. Seems sparking is a bit too early. Running without oil and a broken camshaft -> scrap engine. Thanks for this interesting video, Ivan!

Good for you for sticking to it.

I nailed the diagnosis! I've seen this happen before but the Pico scope diagnosis really added! Loved it!

Have ran across this before: If motor suffered an intake coolant leak in its past, the bearing are damaged and the cam will break or lock the motor up. Always ask customer about coolant loss. Great video Mr. Ivan!

My wife had one of those, great car!! That car is 26 years old!! If it was here in the Detroit area it would be dust the way they brine and salt the roads. When the roads dry it’s dusty like a dirt road because all the brine and salt they pour on all paved roads

I've heard of the cam shaft snapping in 2 on these things and/or spitting out pushrods. But I've never actually seen it happen before. What I've typically seen is blown intake and head gaskets from a bad over heating event. Mind officially blown! Just like that engine. lol. Cool stuff Ivan.

Yeah that’s a very interesting case study ! Thanks for digging in to the problem and giving us the details .

I had an Olds 3.3L years ago that broke a camshaft . Sounded the same, and would barely run at all . Ended up changing motor. Great vid , brought back some memories .

I still miss the old days when first thing done was a compression and vacuum gauge test, but back then in the 60' 70' a valve cover took 5 minutes to remove .

Great diag.. As a electronics engineer I especially relate to the scope work. 80 percent of my time in the lab was in front of a scope. 👍👍👍

I was thinking broken camshaft whilst you were doing the diag, but ruled it out because it was not effecting the whole bank, did not occur to me that the camshaft could have broken mid point, I was thinking more along the lines of breaking off at the sprocket, and that made no sense, so I moved away from the idea. Glad you solved the mystery in the end though!

I've seen wiped cams and spun bearings broken valves and springs broken connecting rods and crank shafts broken lifters bent push rods, just about all the normal mechanical failures that you expect but I don't remember ever seeing a broken camshaft before thanks Ivan very interesting symptoms and diagnosis

Awesome case study. I guess that’s a perfect example for our brain sowing doubts when it doesn’t see what we want it to see. I was thinking of a lose timing gear on camshaft, but that didn’t make sense after seeing the number four cylinder capture.

I know these engines well. Replaced several warped/cracked heads on them too.

@georgehopper4535

Жыл бұрын

The water pump is to high in the cooling system. One air bubble and the coolant stops circulating. There's the cause of cylinder head failure. The first sign of a leak is no heat at idle. 2.8L,3.1L,3.4L.3.5L,3.9L

No such thing as a 5 minute job, not even a crazy buick job with a broken camshaft. After investigation, everything begins to make sense, even the weird data. Never a dull moment when every eventuality seems to have been encountered in the repair spectrum. Very well diagnosed piece of work and on to the next one.

Wow, nice one! Had 2 broken cams in my career, one of them was 3.1l grand am '98 and the other 2001 sentra 1.8l. 👍

Worked on a lot of these motors, intake gaskets would weep coolant into the crankcase, dilute the oil(mayonnaise), after time the cam bearing would seize and snap camshaft in half. Engine replacement. Change those intake gaskets! Change your coolant per manufacturer recommended interval. In this case looks like she ate a cam lobe.

Thanks for linking the Hyundai case. I had been wanting to review it. The tests and the revelations in part 2 should be in the hall of fame.

@stevepark5504

Жыл бұрын

I think that an RC on this Buick would have helped to identify the fault.

Love the diagnostic journey as always. I would have cracked open a few wobbles pops as soon as you pulled the crank sensor and saw the dreaded ferous porcupine. Your usual scientific process is always a joy to follow to convergence. That dude actually drove that car on two cylinders? He is a stubborn man for sure, I like that.

Your engineering mind is such a beautiful thing Ivan!

I have seen 3 camshaft failures in my life time. 67 Firebird round 3 lobes on the cam. Had good oil pressure. (This was a known issue with this car.) Soft cam lobes. 97 Pontiac snapped cam. You know the the Saturn Astra found the rear exhaust cam snapped the at the end were the camp sensor picks up the sync. Great video Ivan. I can't say why but as soon as I saw the wave form. First thing that came to my mind was a snapped cam.

Definitely an interesting and enlightening case study. However, early on in your diagnosis you asked (almost in a rhetorical manner) "could the cam shaft be broken?" So unusual you put that into the back of the diagnostic bus. I am sure you too wondered what on earth...when you saw all those filings collected on the magnet of the CKP. Bottom line..you were correct...the engine is/was toast. Very enlightening for you to bring us along on your diag and thought process as you worked you way through a truly bizarre occurrence.

Ivan, great methodical analysis with all your tools. Running on just 2 cyl, not even 5 ! Yes, broken cam at just 47k is tragic. Had a 94 Camry that would not start, cranking, cranking. Checked plugs, wires, timing belt moving, EFI fuel system good. Problem was broken water pump shaft, water pump pulley part of timing belt drive. Timing belt rotating, but valve timing off enough to not start. Lucky non interference engine. Like electronics, mechanical timing is everything to correct function.

The moment I heard it crank it reminded me of a video I made of a subaru that died pulling into my garage. Same exact type of starting. Turned out the last guy that "rebuilt it" with a new crankshaft left some sort of tape in the engine that wound up in the pickup tube. Oil light only flickered at idle. Definitely threw me in a loop

There was a point early in your diag when you looked at taking the valve cover off, but passed because it looked like a pia to remove. Being old school and I could go with a wench, I would have pulled it because I don’t have 10% of your electronics expertise.

Ivan, when you were going 1,2,3,4,5,6,7 all I could think about was the Beatles song "You Never Give Me Your Money" from the Abby Road album. The lyrics 1,2,3,4,5,6,7 all good children go to heaven I can't get out of my head. Thanks pal.

@PineHollowAutoDiagnostics

Жыл бұрын

Hah hey Denis I thought GM V6 pushrod engines were bulletproof! I guess that only applies to the 3800 ;)

Master at work!! Love all your videos!!

Nice. I remember seeing these in the in the Early 2000s and 2010s with a few broken camshafts . It seems to be common on these Engines. One comes to mind in 2004 when I worked for Buick. The Engine had 0 oil pressure with low mileage.

What a wacky issue! Glad at least you figured out the issue. Thanks Ivan.

Wow, never seen that before. Great diagnose.

At the rear of the 3.1 gm is a oil pump drive shaft. I would pull the intake and pull the oil pump drive gear out. It's probably stripped. Thats why no oil pressure and collapsed lifters. The metal fillings are from the cam lobes got eaten up with no oil pressure. The client should have told you about the oil pressure light on. Once the light came on. The client kept driving. Note. I have the same 3.1 in my 01 Malibu and it's running really good. No burning oil at all. I did change the water pump a while back. My car developed a massive trans leak last week. Engine and transmission are out now. Discovered the transmission front pump seal had walked out. Got a new one installed with lock tight. Got a new rear main seal while I was in it. I'm just replacing some of the other transmission seals since they are leaking too.

Great Research and Diagnosis!

Master tech right there.. keep watching your vidz I'll be just like you. Thanks Buddy

Had an early buick V8 with broken shaft from the bottom of the distributer to the oil pump, this brought back memories. Also had a ford f150 with the crankshaft snapped right at the from main but still ran LOL

Really love all your videos, looks like you guys are getting all the snow, we have not had a storm over 5" all winter long here in Southern New England.

@PineHollowAutoDiagnostics

Жыл бұрын

We've had zero snow since December... Just the occasional dusting that melts the next day. Basically no winter haha

Wow! Something new! THAT was a mind twister. Good one Ivan! The oil pump must have been seized up which caused a chain reaction, or the camshaft may have had a weak spot causing it to snap. HMMMMM!

My neighbor used to have a 3100 Malibu and that snapped a cam, I don't remember the specifics but I do remember him handing me 2 halves.

About 20 years ago we had a customer bring in an older (1981) Datsun 210, 2 door square back. Rear wheel drive. It sounded awful. We yanked the trans thinking the problem noise was in the clutch. Turned out that the crankshaft was actually broken, but it had sheared in such a way that it still ran and drove. I ended up buying the car and cobbling together a 1.4 block with a 1.2 head, swapped the 4 speed for a 5 speed and drove it into the ground. I ran my mother off the road twice drifting it around corners on dirt roads. Good times!!

Great diag and info.thx ivan cheers

Great video brother, as always

As always your diag is tops!

I just had 2 like this in the past month with broken camshafts on the back half. I can’t believe the ran drove like crap. Especially both customer drove them in saying no power and running like crap. Replaced both camshafts in cars and all new lifters cars are back on road. Awesome diag as always Ivan.

@CubasAutomotive

Жыл бұрын

What engines? Just curious

@ChadsAutoandEquipment

Жыл бұрын

@@CubasAutomotive they where both 3.1 engines also. One was in 96 Chevy Corsica. Other was in 98 Buick century. Both 3.1 motors

@CubasAutomotive

Жыл бұрын

@@ChadsAutoandEquipment oh wow!! Ok... I never had one of those 3.1s do that. That's crazy!

The easy way to check for a broken camshaft would be to remove the dummy distributor drive and then you could see if the drive gear on the cam is moving while cranking the engine.

@SHSPVR

Жыл бұрын

That is so true but you literally have to remove the intake to get to it which also means you have to remove the valve covers and a lot of other stuff just to get that intake off I've done many of these over the years

@Hernandez530

Жыл бұрын

Thats definitely a way to check it. But its not necessarily easy lol

@scrappy7571

Жыл бұрын

I remember looking in the oil fill while being cranked over, some valves were moving, others not. Collect my diag fee and move on to the next GM turd.

@stevestadnik9206

Жыл бұрын

Front valve cover is easy enough to remove. Look for how many rocker arms are not moving.

@nickmalone3143

Жыл бұрын

Distributor ? How old is this car ?

broken cams are quite common on those 60 degree V6 engines of that era, when they did the revision from 2.8/3.1 to the 3100/3400 series around 1995 up until about 2004-ish

@SHSPVR

Жыл бұрын

No when that happen you loose cylinder 5 too and root cuases is failed roller lifter which may failed and had jam up the cam and snapped it

@georgehopper4535

Жыл бұрын

@@SHSPVR Lack of lubrication. Did this engine have it's intake gaskets replaced to late? Very low miles. Probably sat a lot as well as short trips. Change your oil every 3 months or 3000 miles. Not every 12 months or 3000 miles.

@Rxdeliveryguy

Жыл бұрын

small port 3100 was 1994-99 and gm's first forray into hollow cams. the big port 3100 and 3400 never had this issue

@scrappy7571

Жыл бұрын

@@Rxdeliveryguy YEAP with cam lobes pressed on to the hollow shaft. What a turd design.

@graymodeler

Жыл бұрын

Yes, I had a 1980 first year of the 2.8 in a Citation. It had a distributor, carb, catalytic converter, and no computer.

Had to plow all day yesterday. They said 1" but it was more like 3". Supposed to get 10 more inches by Monday morning. Plowing and more plowing.

For the first time, I figured out before you. Ha Ha. I was suspicious of a busted cam until you found no oil pressure. Then I was convinced. Couldn’t you hear me yelling at the video, “The cam snapped. The cam snapped?”

top notch diag sir !!

I got it when you gave the big hint that neither valve on cyl 6 was working. I just guessed broken cam shaft. Lucky guess on my part. I am a much better Nurse than mechanic :)

Interesting case study and proof how important it is to collect as much data as possible. You may not understand it at the time, but as you demonstrated here you were eventually able to correlate the data with the actual failure. I see some people are saying a catastrophic failure of a roller rocker arm can cause a camshaft to fracture. The data supports a fractured camshaft regardless of the root cause. That would take a post-mortem autopsy.

Wow this was crazy. Great video

Did enjoy this! Thanks as always!

As soon as you said no oil pressure I figured it out. Last cyl dead, no oil press. = broken cam.

Also those engines are notorious for having head gasket leaks and intake gasket problem now as for their sensor in the back of the motor you can get to it, it's just a bit of a pain you'll need to do it from underneath the car or like you did from wheel arch depending on which make and model vehicle you have and it helps to have long arms too I've done quite a few of these 3100/3400 hundreds many times over the years. Seems to me more likely you got a failed roller lifter which may failed and had jam up the cam and snapped it at the back two cylinders five and six because that is an awful lot of metal on that sensor. Oh and you're correct getting the valve cover off is a real pain in the neck because you have to remove that torque bracket and the water crossover pipe which go to the heater core and the throttle body too

Cool view man! Thank you

1990s and 2000s GM V6s are in the salvage yard where the 1MZ-FE V6 are still on the road at 300K+.

This was defo a hard one. I would never have thought a broken cam. Only seen a broken CRANK on a 1959 Mini 850ccm - and that one would run with a very scary rumble and overheat.

Ivan great video. In my 50 years I have seen 1 camshaft snapped in two. It was a VW diesel that had snapped the timing belt. After removing the head a replacing all the valve's and lifters the car ran great. 2 weeks later it snapped the camshaft in two. I think when the original belt snapped it shocked the cam and weakened it and then 2 weeks later boom.

@brianw8963

Жыл бұрын

In my 50+ years, You got me beat by 1.

@tam1381

Жыл бұрын

@@brianw8963 Ahh another youngster....LMAO

@brianw8963

Жыл бұрын

@@tam1381 And still learning! 👍🇺🇸

@tam1381

Жыл бұрын

@@brianw8963 me too.

Those crank sensors like to break off in the block too. Haven't changed many though. Reliable engine. Original intake gaskets were plastic. And the oil pump drive gear/distributor blank o-ring seal were the only weaknesses. Several friends and family members owned and still own.

The broken cam made shavings which are the ones you saw on the crankshaft sensor magnetic end messing with the signal on it. The Ford Vulcan 3.0 V6 has a similar design driving the oil pump, but they have a cam sensor on the upper drive (old dist. loc.). I've experienced a few broken cams in three Hondas but none in the Buick engines. I have had an oil pump seize up in an SBC that stripped out the drive gear. This was an interesting cause and effect scenario to watch with your diagnosis.

About 40 years ago, when I was still in my youth, a bubbly had an old Chevy Chevette with a small 4 cylinder OHC engine that had a broken camshaft. It was doing exactly what this engine is doing. We replaced the cam, flushed the crankcase, and he ran the car for another 2 years.

Back in the days around 2000 GM had many camshafts broken in half. I bet I replaced over 50 at that time myself. It was determined to be materials contamination in the casting of the cams.

Fixed an old Renault with the same metal filings fault. A friend had a starter failure. Garage replaced that but then it ran like a bag of shite. The garage didn't have a clue and told him to scrap it. I noticed the timing dancing about with a timing lamp. Popped the crank sensor and found all the filings built up from the failed starte dog.

You should catalog your known good peco scope data from all your repairs. It would be worth a gold mine some day and maybe even create your own diagnostic website to sell the data.

2003 Malibu 3.1 engine 180k miles: My GF's car. I replaced the IMG's and injectors. Then I had to repair two rocker bolts that pulled from the head. I really do not think its such a bad engine. I mean the one in the video is from 97' and thats over 20 years old. Maintenance is pretty key also and how you drive it. These engines are relatively easy to work on too.

Had a friend with an older Ford f150, I believe it had a 302. Developed a knock and I thought rod knock. Ordered a short block, installed back in business. Went looking at pulled engine and crankshaft was broken in the middle in a way it bonded but kept running. Damn....

Initially I thought bent valves, as I had a GM/ Daewoo 4cyl sound similar when trying to start after replacing a broken timing belt. But your testing ruled that out.

@juanrodriguez-ry6yt

Жыл бұрын

non interference engine like most american v8's of that era

Great case study.if the rest of the vehicle is good shape maybe go with a Jasper replacement engine. That’s just a thought . It’s really up to the owner to decide.

When you said you'll never guess what it is, I guess to myself it was a broken cam shaft. I totally nailed it.

@PineHollowAutoDiagnostics

Жыл бұрын

Nice lol

Hey Ivan another strange thing you would have seen if you had performed a relative compression test is double the cranking amps on each exhaust stroke of each cylinder that had a problem . The cranking speed slows down because the starter is compressing air in 2 cylinders at the same time .

Never ever continue to run and drive a car with an oil light I think is the moral of this story was a strange one though, I'm glad you figured it out it made for an interesting one for sure.

Bizarrely it is exactly the first thought I had, but I've seen a broken cam on a UK 4 cylinder vehicle and the cranking sound was similar, that one however did not drive the oil pump from the cam but it was one of those things that triggered the instant memory of 'cam broke'. Thing is, because it is such a rare thing to happen I would have second guessed myself right the way through to pulling the valve cover for a physical inspection.

These symptoms had me really thinking. I also wanted to see if your camera could look into the area where the camshaft position sensor sat. I want to know what is going on with all those metal filings. It won't help this engine to know but I was curious about that. Definitely a nice weird one. I have great admiration for your skills, knowledge, and easy going personality.

@gerrymoeller

Жыл бұрын

The broken camshaft chewing up against the other half is the cause for the shavings.

@hpelisr

Жыл бұрын

Yes I was thinking the same, those metal bits are not in the camshaft function.

@SHSPVR

Жыл бұрын

@@gerrymoeller root cuases is failed roller lifter which may failed and had jam up the cam and snapped it

Ivan, loved the diag. Wow, the cam shaft sheared off. Who "wooda thunk it,." ha, ha.

With the age of that vehicle soon as I seen all the metal on the crankshaft positioning sensor the diagnostics would’ve been over. Seriously at that point there’s no sense going any further wasting another penny on that dinosaur. You’re better than me I would not have seen that through. Clearly the engine is junk and it’s way too old to be worth fixing.I love watching your diagnostics I have learned so much from you

@PineHollowAutoDiagnostics

Жыл бұрын

Hah the metal shavings was just the tip of the iceberg!

Wow! That was crazy, Thanks!

I also immidiately thought of the legendary video you did with Eric O. (by the way: we need some of that again^^)

Now I’m no expert but guess it was a snapped camshaft early on , I’ve seen about two cars do this on rainmans channel, great video 👍👍👍

I've seen and heard of others with a broken camshaft. It was my thought halfway through when you saw the double compression in the rotation of #4

Yep. I had camshaft snaped so only first lob was turning. It was Opel Ascona 1.6 petrol engine. Since I couldn't ride it, rest of the engine was ok, so changing camshaft fixed problem.

Would love to see the tear down.Crazy video for sure

I almost forgot about all of the warranty short blocks for piston slap. Special policy clam only if the customer complained about the noise.

That was a very cool episode/video

Back in the day 15 to 25 yrs ago, i used to encounter snapped camshafts fairly often... to the point I'd look for that on some cars. 4 cyls is what I would see it most often on... I believe 1 was a Japanese nissan or Toyota. Never seen that on a 3.1 though 🤔

Great case study! Research, Research, Research! How would someone without pressure transducers figure it out? Good idea to remove the oil filter. I have never heard of a camshaft snapping! You are the man!

@truracer20

Жыл бұрын

Without a pressure transducer most older mechanics would remove the valve covers after seeing odd readings with a compression tester. Failed cam lobe, failed roller lifters, failed rocker stud, failed pushrod etc. There are alot of failure points to be discovered under the valve covers when you have compression, spark, fuel and air accompanied by a dead miss. Once he found the metal shavings on the crank sensor while determining correct ignition signal the valve covers needed to come off. Those shavings were not the normal fine powder you might expect, they were evidence of major internal failure. Not knocking Ivan but his pressure transducer did not diagnose the problem. It was research after the fact that led him to find the common failure. Yes he did use the information from the transducer to validate his research findings and because of that he did suspect a broken cam. But he didn't call it until after he googled the answer. He could have also found the same information in Mitchell or Identifix etc. In those forums you'll find it's much more common than you'll find on Google. Most laymen don't get into the minutiae of why their engine needs replaced. Regardless of what some GM fans believe this was common, and is attributed to many flaws of this engine, coolant leaking into the intake then into the cylinder, past the rings and contaminating the oil. Or the fact the cam journals are misaligned, or that the camshaft is hollow. Mix a hollow cam with misaligned journals and you get an easy visual of why it might break. Add in contaminated oil for a loss of lubricity and the picture is complete. Some failed under warranty, most failed out of warranty. I suspect most that are still on the road are those who failed under warranty. Though this specimen looks to be the latter, 100k is prime mileage for this failure. There was never a TSB for this problem that I'm aware of but at the time it was common knowledge. A dealer tech in 2000 would have checked oil pressure, found none, and pulled the pan.

I personally owned a dodge shadow that broke a cam shaft Into two pieces like it was cut with a knife. Engine oil pump was connected to that portion of chain if I recall. We couldn’t figure out why we had zero oil psi, and 1 cylinder dead. Blew my mind when we removed valve cover. I was 17 at time and no one would believe I wasn’t driving at 10k rpm or some thing for that to happen.

i used to avoid all exhaust jobs too...but i never turn down a catalytic job...the scrap value of the bad ones makes it worthwhile

It's actually a 60° Chevrolet V6 engine rather than the 90° 3.8 litre Buick V6 engine,so the 2.8-3.4 litre V6 engines are the 60° Chevrolet V6 engines !