2014 Silverado 1500 4.3lt with AFM

[Graeme Carlson]

Alright… I’m in over my head, i took my truck to 2 different mechanics, one said it might be exhaust manifold leak so I changed that, other said it was a bad lifter, opened it up and lifters are operating properly! Symptoms are as follows…

 

- Ticking sound seems to be from left side of motor

 

- Check engine light with misfire in cylinder 5

 

- 120 pressure on cylinder 5, others have 200

 

- When reving engine the ticking is louder, it’s more of a deeper tick

 

Any insights or if someone has had this problem I would greeeatly appreciate it!!!!

[CamGTP]

Did you remove the lifters or just look at the pushrods and rockers moving up and down?

 

The ticking could be a bad lifter that wiped out the cam lobe.

[rlcole321]

If it is not a lifter/push rod/cam issue, another problem could be a leaking injector seal in then cylinder head, this is a direct injected motor, the injectors spray directly into the combustion chamber and could account for the lower compression.

[newdude]

On 2/5/2024 at 9:54 PM, Graeme Carlson said:

Alright… I’m in over my head, i took my truck to 2 different mechanics, one said it might be exhaust manifold leak so I changed that, other said it was a bad lifter, opened it up and lifters are operating properly! Symptoms are as follows…

 

- Ticking sound seems to be from left side of motor

 

- Check engine light with misfire in cylinder 5

 

- 120 pressure on cylinder 5, others have 200

 

- When reving engine the ticking is louder, it’s more of a deeper tick

 

Any insights or if someone has had this problem I would greeeatly appreciate it!!!!

 

 

AFM cylinders on the 4.3 are cylinders 3 and 6.  

 

Sounds like you've got a bad camshaft and lifters on cylinder 5.