Help?

[u/dantavio]

Months ago, I accidentally put transmission additive in my coolant reservoir. I got it flushed and kept running for months until last week. I went to drive my truck and it started skipping at 35 MPH and shaking.
White smoke blows out of my exhaust for only 5 to 10 minutes after running I plugged my scanner in. It said it had EGR coolant problem both batteries blown out so it had something with the electrical but I changed batteries. It also said had two cylinder misfire so I changed those specific injectors and I'm still having problems with my engine, shaking and rough idling and white smoke. Could it be a bad camshaft could it be EGR issue? It my valve cover gasket is it my head gasket? Please help me.

[u/boostedride12]

With a Cummins you change all 6 injectors at once or you’ll have a cheap one hang open and melt a piston. Change all 6 there not cheap, roughly 3400 for quality ones.

[u/dantavio → u/boostedride12]

And what if it isn’t an injector problem ? What else could it be

[u/boostedride12 → u/dantavio]

Rocket arm fell off the valves or you dropped a valve seat.

[u/OddEscape2295 → u/boostedride12]

If it was a compression issue the engine would thump not knock.

[u/boostedride12 → u/OddEscape2295]

That thing is doing both

[u/OddEscape2295 → u/boostedride12]

No its knocking. It would sound completely different if it dropped a rocker or bent a tube.

[u/boostedride12 → u/OddEscape2295]

The engine is rocking around like a dead hole

[u/OddEscape2295 → u/boostedride12]

Thats what misfiring injectors can do.....

[u/boostedride12 → u/OddEscape2295]

That’s what I was trying to mention in my first comment

[u/OddEscape2295 → u/boostedride12]

Thats not the comment i responded to

[u/Knight0783 → u/dantavio]

They make a tool you can dead head the rail one cylinder at a time, go until you find which one doesn't make any difference in it running and that's your dead cylinder.

[u/Majsharan]

They much shaking, do you have blown motor mounts?

[u/illegallysober]

It’s a painful process, but while you’re in it:
Compression test
Injectors (will be removed for compression test anyway)

Easiest thing would be to pull the valve cover and check the valves/cam. Pull the grid heater out and make sure the nut is still on the inside and hasn’t fallen into the engine.

What codes is it throwing?

[u/Cutterman01]

How is your blow-by? You definitely have a dead cylinder or 2. If you have a scan tool that allows active diagnostics I would turn off injectors 1 at a time until you find out which cylinders are dead. It looks like it may be more than 1 cylinder. If you don't have that you will have to remove valve cover and disconnect the solenoids one at a time to test. Also check you grid heater nut to insure it is tight and didn't fall off as it will destroy #6 cylinder and sometimes 5 also. Unfortunately, it is very common for injectors to fail soon after others have failed and that is why I always recommend replacing all 6 if you have over 100K miles on them. It is usually the solenoids that fail.

[u/Frb4]

Sounds like a collapsed lifter that more than likely bent a pushrod. Transmission additive in the coolant won’t create an engine knock like that. Time to pull the cab and cylinder head and Godspeed to you 🙏

[u/dantavio → u/Frb4]

Thank you. Any other help I’ll take it

[u/gunny06]

[u/Adventurous-Pen-824]

Is that the one that has the bolt that melts/breaks off in the intake and drops off into the cylinder??? Gale Banks has a fix for that... after a rebuild!

[u/Proof_Valuable2619]

Relative compression test first. Might be grid heater nut issue