2016 Engine comp rattle on acceleration plus power loss

[geo2515]

Greetings all and sorry for the broken record/ engine rattle post. I just cannot find an answer to this thing. I have this loud rattle knocking sound on acceleration- (like entering the freeway on a short ramp hitting it to get going). In neutral I can run up to 4k rpm and it sounds completely normal. The only time this sound is going on is on a hard throttle and nearly instantly on the downshift. There is a very slight stutter and decreased power when it does this, like a slipping feeling and sometimes what seems like a pop in the exhaust pipes. I duplicated this on the road for a dealer service tech about a month ago and after the only code was a misfire #5. They recc a spark plug change...

I have not yet replaced the plugs but inspected several coil packs and there is some green corrosion on some but not all the contacts. They look normal otherwise.

To save space I'll say the truck has been regularly and properly maintained- oil, trans, front axle bearings/joints, front ds, rear ds....Temps are all normal- 198/170/217

What could possibly be making this knocking sound under load and is it actually engine related or possibly exhaust headers? I don't know what a faulty exhaust header sounds like but this noise almost sounds like it is from under the motor area. Do worn coils/plugs make a rattle sound?

 

[mtofell]

How many miles on the truck? Are you getting a flashing CEL indicating the misfire?

My 2014 suddenly developed a rattle/knock around 115K and flashing CEL on moderate/hard acceleration. You probably don't want to know the end of the story - the dealer tore into the engine a bit and found metal shavings and it needed a new engine.

 

[geo2515]

It has 103k miles. The CEL has never came on for any reason. Well if it is the motor going out I am clueless as to the cause. It has been well cared for and the previous owner’s records are likewise. Is there a root cause like an under performing oil pump or something? It seems like what I’m asking is often an issue and a $60k truck (new) shouldn’t have a 100k engine life.

 

[geo2515]

Could this possibly be trans related and locking up under load?

 

[geo2515]

The idle has gotten a slight jitter since last oil change slightly jumpy. There’s a prominent ticking at cold start then dies down after several minutes. Oil level is good. Coolant is good tho due for change no discolor. No leaks on any fluid. Actually the only fluid I’ve seen and somewhat ignored is the rear ds yoke is tossing a small amount of trans fluid. It is an issue yes but I didn’t consider it part of the rattling sound at the engine.

 

[geo2515]

Just want to follow up in case anyone has similar symptoms with their truck.

The issue I was having is completely fixed. I replaced two spark plugs and coil on cylinder #5. Idles smooth as a top… No throttle rattle noise on acceleration.

I thought I’d step back and take the dealers tech advice. The plugs however looked fine, in fact extremely clean like new. The coil I discovered was not original and was replaced at some point by after market. This coil was in bad shape, boots were brittle and one was stuck and inner spring was corroded bad.

 

[mtofell]

The coil I discovered was not original and was replaced at some point by after market.

Good news that your issue is currently fixed. It is curious, though, that the original coil failed and was replaced (apparently before you owned the truck) and that the replacement failed. The odds of two coils failing on the same cylinder without some underlying problem are pretty long.