When I wrote the headline “My Chevy Silverado’s 350 V8 Just Blew Up For No Apparent Reason,” I think we all squinted a bit and thought: “That doesn’t really pass the laugh test.” This is a smallblock Chevy motor we’re talking about; they don’t typically run fine one moment and then blow up during startup the next. What, then, could explain the metallic banging noise coming from my engine?
I actually sorta-answered this already in my follow-up article “Turns Out My Chevy V8 Engine Didn’t Blow Up, But It’s Being Weird And I’m So Confused,” but the truck — despite no longer producing the horrible knocking sound you hear in the video below — was now overheating.
Or so it appeared on the gauge.
I only figured out the full cause of the problem when I replaced my wobbling Saginaw Steering Column:
Four bolts in the steering column had completely unthreaded, leaving me with a ridiculously wobbly steering column. Since starting the engine involves rotating an ignition switch relative to the steering column, when that column wobbled and all of its internals got all floppy, the ignition switch tended to bind up.
I don’t know if any of you have ever accidentally forgotten that your car was running, and then tried starting it. But if you have, you know: It sounds horrible.Â
There really is no other sound like it. or I’d try describing it. It’s almost like something metallic being stripped. Someone who accidentally did it to their Toyota FJ Cruiser described it on a forum, writing:
The noise when you try to start a car that is already idling of course is that horrible kind of sharp high pitched grinding sound that makes you jump out of your seat and cuss your stupidity.Â
A Redditor also tried describing it, writing:
There has been one or two occasions when the car’s started but for some reason, while waiting in parking lots, I forget if I’ve turned on the car or not. If I try to turn the key when its already started, it makes some weird horrendous almost wheezing like sound. What’s going on?
Here’s a response to that Reddit thread:
A really really horrible noise. Do it too many times and you could hurt the starter or flexplate/flywheel. Avoid doing it if you can.
You get the idea — this is a sound that’s universally considered among the worst sounds in all of automotive. And it’s why I had figured my motor had blown up.
On plenty of occasions, I have heard this sound of a starter jamming up against a flywheel (see gif above and video below by the same guy, Warped, who put a Gopro inside a tire) that was already being spun by a running engine, but for some reason, it wasn’t immediately obvious that that’s what was happening to my 1989 Chevy K1500.
Only when I kept cranking the motor, it started running, and the grinding noise went away, did I know that that’s what the noise had to have been. There was no other explanation. And my wobbly column had very clearly been a contributor.
I bolted the four loose fasteners in the column, installed a new ignition switch, and now bob’s my uncle. The truck runs and drives perfectly, and the starter and flywheel seem to be totally fine, with the motor cranking quickly and firing every time. There’s also no overheating — something I’ll just chock up as an electrical glitch associated with the wonky ignition switch.
Just listen to this beauty and its rusted-out muffler:
After hearing that horrible knocking noise, this outcome really was the best-case scenario. I thank the car-gods for their mercy, and I apologies to the Chevy V8 gods for doubting their glory.
I tell you what, that loose steering column was much needed information for those of us trying to do internet diagnostics.
I can hear it now David trying to remove his engine, and its screaming out “I’m not dead yet”
I guess push button start has an advantage after all.
Right? My car is smart enough to know it’s already running and then say, “Okay, moron. As you wish” and shutdown. Serves me right. Maybe it’s time to consider an Uber/Lyft.
“I bolted the four loose fasteners in the column, installed a new ignition switch, and now bob’s my uncle.”
I assume Bob’s not his real name?
or maybe Bob is his name but not his real uncle.
Well, he’s technically his dad’s cousin but was around a lot during David’s formative years.
Actually, he’s just a friend of David’s dad.
Turns out, he is just some guy that would go to the same bar that David’s dad went to.
Or his mom.
Bob (not his real name) is on Elise’s side of the family.
I’ve had multiple occasions where a mis-diagnosis has me thinking my engine has failed.
I once dumped my 4.0 Jeep XJ on the shoulder and had it towed home, after noticing it was knocking and the oil pressure was low after 5 hours on the highway.
Turns out I just hadn’t tightened the bolts on the viscous fan properly and it had come loose. The low oil pressure was just because I was idling after 5 hours at highway speed on a hot day.
I also thought the engine was failing in my wife’s 4.0 Jeep ZJ when the water pump failed, which also caused a knocking noise as the pulley/fan flapped around.
I worry now that if my engine ever does actually fail, I’ll dismiss it as being “probably something else”.
I’ve followed this story closely, as your response to the initial incident is exactly how my brain works as well.
Case in point: the night before last, I decided to investigate the (hydraulic) valve train noise that my ’79 VW bus developed on a recent trip. I discovered a knackered adjustment screw on the #3 intake, swapped it with a spare I had lying around, and re-adjusted all of the valves for good measure. I got everything buttoned it up and jumped in it for a test drive, only to have the valves clatter even worse than previously. My usual method of correcting this is to drive it gently for a few minutes until the lifters pump up, but this time the noise got worse, and the motor was clearly down a cylinder with a “metallic bits banging around in the engine” bonus. As the kids say, I was sure it was cooked.
I limped it back home with a head full of worst-case scenarios and a multi-thousand-dollar repair bill. I let it cool enough to pull the valve cover on that side, and the locknut for the number three intake adjuster fell to the floor. Well, that certainly explains the noise. A couple minutes to get the motor to the proper position, re-set the adjuster, and lock it back down was all it took. The motor sounds and runs great.
Glad yours does too!
I spent a good part of last summer/fall worried about a “lifter tick” that I have now chocked up to being a noise coming from the ac pulley.
Thank you for the closure David 🙂
Ugh. I just got my van back from a flex plate replacement. My sound was a bit different in tone and frequency, but this article is still giving me PTSD. Thought I was done listening to broken starter-transmission interfaces.
What’s next to fix? The muffler?
I am quite superstitious with cars; if he fixes the muffler then a whole bunch of other things are going to fail disastrously.
100% this… Before I parked my G35x Safari up North, I figured I’d fix everything that needed attention. The last thing I did was fix the muffler. Aside from being a Nissan, that car was perfect when I parked it. The next time I drove it, power steering pump decided to only work intermittently. I’m leaving that broken for now, so the universe doesn’t break something worse.
If he fixes the muffler, then he’ll hear every problem that he couldn’t beforehand.
The overheating and revving to WOT doesn’t make sense if the root issue was the column though. But I’ve learned that sometimes it’s best to just take the win and not question it too much.
Definately something funny with the electricals, which you wouldn’t think would happen from wires in the steering column… but also ’80s GM.
There’s a typo in the graphics. “Saiginaw Wobble” has too many is.
Great fix, definitely didn’t foresee this as the remedy. It never ceases to amaze me how one seemingly unrelated problem (loose steering bolts) can contribute to something like a stuck starter, which presented itself as a much worse problem! Also agree, that’s about the worst sound there is…. yikes!!!
UFTA! Yeah, that’s a bad noise. Glad it turned out so well!
Have you never been to a 24 Hours of Lemons race?
The same series where Alfa Romeos and Cadillac 4.9s are somehow more reliable choices based on their track records.
Two cars back, my DD was a 2002 Crown Vic LX Sport with the venerable 4.6 liter V8 in it. Meticulously maintained by its original owner for 30-some thousand miles and me for the next 50 thousand or so. Always had synthetic oil and changed around 5,000 miles. Car ran and drove without issue.
Around 84k miles, I was surprised to hear a lower-end knock when it started and when I turned the engine off. A real awful rattle that matched engine RPMs. I figure a bearing was spun or something was about to come apart catastrophically. I took it to my mechanic, who was a good guy and he diagnosed the bottom end being out of it. He didn’t disassemble it or anything but said it sure sounded like the engine needed major work (and there was no charge for his diagnosis).
But since the car ran and drove without issue, he was a little dubious about the diagnosis and said to get a second opinion before spending any money to fix it.
I took it to another place and they diagnosed the actual problem: a loose catalyst in my right catalytic converter. Loose enough to rattle and resonate like a dying engine. Around $450 or so later, a new cat was in place and the “bottom end noises” my engine was making were gone.
I love those cars!
Sounds similar to a muffler bearing
I’ll see myself out…
For a second, I thought you were telling my story of my 4.6 when a serp belt tensioner went while I was racing.
Made a perfectly matched engine speed metal on metal clank as the tensioner was flapping in rhythm hitting something internally.
Biggest scare that had me, also someone who wrenches and swaps engines, thinking the engine was gone.
Similar but different story: I did a timing job on a V8 Tundra. After buttoning everything up I finally started the engine and heard the unmistakable sound of a noisy valve. How?
After freaking out for a bit I started working to isolate the sound. Somehow I had the upper timing cover slightly crooked and it was vibrating at the same speed as that bank’s cam.
The sticky plastics and wear plastics and electronics are the down fall of alot those. The light switches are a big pain along with all the column electronics and the column theirself. The TBI can get a weird grounding issues too that I’ve never really found explained it’s just a thing.
Do starters turn into generators when spun by the flywheel?
If so, maybe a higher voltage was throwing off the temp sensor circuit.
They usually have a one way clutch to prevent being oversped by the engine.
We are relieved. Maybe that is the karma for doing the hard work of moving on your own.
So glad it wasn’t anything more serious (and costly).
Why did it red line?
It’s a good question. It does rev at startup normally; I wonder if it just sounded like redline due to the starter. Hmmm
I jumped to my guess of smog pump after reading without listening to your recording because your symptoms reminded me of mine. Could be a bad seal or vacuum line(s), sticky linkage. How’s the gas mileage unloaded?