Guess what, lifter noise, I think..

[TAHOEBLACKONBLACK]

Over the past few weeks, my 07 Tahoe has had this intermittent ticking noise. Almost sounds like a diesel. It doesn't tick when the vehicle is first started. After idling, it'll start. Will start driving and it'll go away. Sometimes it comes back while driving, even on the hwy at like 75mph. Yesterday, I put some motor flush in it and let it run for about 5 minutes. Drained oil and refilled with 10W30 full syn mobile 1. The ticking went away and then after driving for about a mile, it came back after sittin at a light. As soon as I hit the gas, it went away. This morning, it started again for about a min or two then went away. Using common sense, something has to be clogged. Any reason on what's causing the clog? I read it could be an oring online with the oil pump. My oil pressure is normal I assume at about 25psi at idle and goes up as the rpm does. Any help? Please..

 

[PaulS63]

Does this have AFM ? If so, try disabling it, might help with this

 

[TAHOEBLACKONBLACK]

Yes it has AFM, but I don't think it's the cause. Had a oil pressure sensor code. Seems something is clogged and bad oil sensor

 

[OR VietVet]

Maybe the oil pump pickup screen o-ring is bad. I would like to see 40 psi pressure at idle. Replace the oil pressure sender and get a cold to hot idle and higher rpm oil pressure reading while you have the sender off.

 

[TAHOEBLACKONBLACK]

Maybe the oil pump pickup screen o-ring is bad. I would like to see 40 psi pressure at idle. Replace the oil pressure sender and get a cold to hot idle and higher rpm oil pressure reading while you have the sender off.

Thanks. I actually will change that oring Monday. I changed the oil pressure sensor, cleaned filter, changed oil filter. Problem still recurs. Changed the oil sending unit at about 110,000 and it has 200,000 right now. Also, don't think that's it's because when the pressure goes under 20 psi, the lifter chatter starts. Think the gauge is accurate. I'm leaning toward the Oring because today the psi while driving was above 40 psi. Good indication of leak at oring, causing lost of pressure. If it ends up being the oil pump, I'm trading her in for a 14 and be done with it..

 

[TAHOEBLACKONBLACK]

Maybe the oil pump pickup screen o-ring is bad. I would like to see 40 psi pressure at idle. Replace the oil pressure sender and get a cold to hot idle and higher rpm oil pressure reading while you have the sender off.

It was the oring! Replaced and oil pressure is stable now

 

[StockHoe]

Research Piston Slap.....I got it too.