Misfire Problem - Could use some help

Thanks for the replies everyone. This is one of those situations that I'd like to have a very experienced mechanic at my side with the right diagnostic tools and experience to help me diagnose this problem. I know some stuff, but I've obviously still got lots and lots to learn. Back to the drawing board,
 
You've gone through all the right steps so far. There isn't much left at this point.

I would suspect wiring between the ECU and injector at this point. You replaced most of the air/fuel/spark components...

It might take putting an oscilloscope on some signals in the engine bay, which is getting pretty advanced.

-Charlie
 
Crankshaft Play

Well Dudes,

I was editing a video we made of checking the timing on Greg's engine and noticed something very disturbing with his engine. There is massive play in the crankshaft. I had to turn the engine over with the crankshaft pulley bolt so I could view the timing mark on the pulley so I'm very confident this is not the pulley sliding back and forth on the end of the crankshaft because that bolt would have to be pretty damn loose to allow that much movement. Another thing is the woodruff key doesn't engage very deeply into the pulley so the amount of movement seen in the video can't be from a loose pulley. Also, if the pulley was that loose, the pulley would be wobbling.

After doing some research, I think one or both of the thrust washers has given way allowing the movement with the crankshaft. I'm now 99.9% sure I've found the cause of his engine knock. And, with that kind of movement in the crankshaft, I'm thinking the source of the #1 cylinder misfire is most likely coming from the crankshaft position sensor.

Let me know what you guys think.

<iframe width="560" height="315" src="https://www.youtube.com/embed/uxvXicCba6o" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
I would agree 100%. Can you see a wave signal using Techstream for the crank sensor to see if it changes before the CEL is triggered after 50 miles? If it does, well there is your proof.

Maybe the crank bolt wasn’t torqued correctly from some time before.

If it turns out to be the case you now have a video for an engine swap if he decides to go that route if you guys are up for it.
 
I hate stuff like that!! I don't know of to many of these that kicked a thrust bearing but I've seen other cars do it a good bit...you could drop the pan and slide a new one in lol but that would be a bandaid. Surprised that it didn't pop out the front crank seal...now the guy has to figure out rebuild or replace.

Sent from my SM-G955U using Tapatalk
 
[MENTION=120071]mtbtim[/MENTION], couldn't tell from vid.
Max Thrust clearance is .0118", if crank is moving more than that shims are toast well done. No bandaid can fix this long term.
Engine swap Vid like [MENTION=69868]LittleCaesar[/MENTION] mentioned could make it to production.
Then you could do a teardown inspection how to Vid for those that want to know, Lol.

Edit: Just saw crank end play thread. Run it till it quits, Not for me.
 
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I had the thrust washers fall out into the oil pan on a (poorly, before I bought it) rebuilt engine in an old Camry. Every time the clutch was pressed, it would want to stall (crank side loads). I'm not sure how it would act with an auto without the crank side loads involved...

The oil was a glittery mess after I drove it home from work - at least it gave me an excuse to do a motor swap! :lol:

-Charlie
 
Somebody commented on the video on our channel and mentioned the possibility of a separated harmonic balancer causing that play. Could a harmonic balancer move that much in and out and not wobble or disintegrate after not too long? According to Greg, his engine has been making the knocking noise for 2+ years.
 
Tim, I always would hear at the station, and from dad/grandpa, the reason Toyotas are "bullproof" is because when something fails, it will still run forever.

Both had owned Toyotas since they were brought into the US. Both told me never mess with a Toyota transmission or engine until it completely stopped working, burned/lost too much oil, or had unusable MPG.

How many cracked flex plates have we heard of going "60k and still ticking"
 
My uncle had a 98 350 in his k1500. No lower engine knock but he had a serious crank wobble but drove it well over 100,000 miles with no real problems to speak of. Tell Greg to drive it until he is up for an engine swap.
 
LittleCaesar said:
My uncle had a 98 350 in his k1500. No lower engine knock but he had a serious crank wobble but drove it well over 100,000 miles with no real problems to speak of. Tell Greg to drive it until he is up for an engine swap.
Click to expand...

Well, the problem is he can't get his rig smogged with the misfire CEL. His registration is expired by around 8 months now. That's why I've been trying to help him figure this out.
 
I would just do an engine swap and be done with it. I wouldn't want to drive around with a problem that serious knowing that it could give up the ghost at any moment. Could it run for several years? Sure. But if he can't pass emissions he has a 4500lb paperweight.

If I can do an engine swap, in my garage, in winter, in Wisconsin, you guys could get it done in a weekend no problem. It only took me a couple weeks and that was by myself a few hours at a time. Lot's of guys here have done it and will be able to help with any questions.

It's a crummy situation none the less, been there done that. Of the 10 or so vehicles I've owned, I've blown 5 engines and I take good care of my stuff.

It'll be a perfect opportunity for a really helpful vehicle for the community if you guys end up doing it (and if Tim is even more generous then he already is and helps with this). Let's face it, as reliable as these trucks are, they are getting old and more of these engines are going to start failing for one reason or another.

Either way, good luck to the OP! Hopefully you guys can figure something out so he can get back on the road (legally).
 
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mtbtim said:
Somebody commented on the video on our channel and mentioned the possibility of a separated harmonic balancer causing that play. Could a harmonic balancer move that much in and out and not wobble or disintegrate after not too long? According to Greg, his engine has been making the knocking noise for 2+ years.
Click to expand...

I doubt that, it looks like the whole HB is shifting forward because the crank is moving. I'd think if the HB was separating, you would see it in the video. To me, it looks like the crank itself is walking and it explains the engine knock/misfire.

Have you looked at the oil real closely on the dipstick? With a knock and that much play in the crank, there should be some glitter in the oil.
 
mtbtim said:
Well, the problem is he can't get his rig smogged with the misfire CEL. His registration is expired by around 8 months now. That's why I've been trying to help him figure this out.
Click to expand...

That is correct, I should have known. But I would send an oil sample to Blackstone.
 
mtbtim said:
Well Dudes,

I was editing a video we made of checking the timing on Greg's engine and noticed something very disturbing with his engine. There is massive play in the crankshaft. I had to turn the engine over with the crankshaft pulley bolt so I could view the timing mark on the pulley so I'm very confident this is not the pulley sliding back and forth on the end of the crankshaft because that bolt would have to be pretty damn loose to allow that much movement. Another thing is the woodruff key doesn't engage very deeply into the pulley so the amount of movement seen in the video can't be from a loose pulley. Also, if the pulley was that loose, the pulley would be wobbling.

After doing some research, I think one or both of the thrust washers has given way allowing the movement with the crankshaft. I'm now 99.9% sure I've found the cause of his engine knock. And, with that kind of movement in the crankshaft, I'm thinking the source of the #1 cylinder misfire is most likely coming from the crankshaft position sensor.

Let me know what you guys think.

<iframe width="560" height="315" src="https://www.youtube.com/embed/uxvXicCba6o" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
Click to expand...


I actually discovered this same exact issue a few years ago when I took my Runner to a shop for a TB change. They wouldn't touch it once they discovered the play in the crank shaft. I created a post here about it back when this all happened. I haven't had any issues (including some moderately tough wheeling up Lippincott Mine Road in DV) but have recently gotten a mysterious misfire when the car drives for a couple hours on the highway which I think may be related to fuel injectors or coils.

Edit: Here's a link to that thread I created a few years ago. Crankshaft End Play!
 
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Crankshaft Play Part 2

Well Dudes,

It is confirmed! The play we saw in the last video is indeed all crankshaft play. I got Greg back over the house today and we were able to verify without a doubt his engine is screwed.

<iframe width="560" height="315" src="https://www.youtube.com/embed/9Gpdq-tL79U" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
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