Ticking sound

could it be valve ticking?

 

You know that ticking noise that sounds like a lifter? It's not a lifter. It seems to have stumped everyone here in the chat. My 07 started doing that a couple years ago. Listening with a mechanics stethoscope, I determined it was not in the valvetrain, but somewhere in the block. The tick would go away when the engine became unloaded, as when the computer decided it wasn't needing to charge the traction battery any longer. My fuel economy dropped into the low 30s to high 20s mpg. I suspect the knock sensor reported the knocking to the computer who began retarding the ignition timing. I suspected I had one or more slapping pistons. I have seen in other engines that they can go a long way with a slapping piston so I continued to use the car for 2 more years, about 20,000 miles. The tick eventually got louder so I bought an unsalted engine with 119K from a Florida auto salvage for $600 and swapped it out. My fuel economy jumped way back up, on level roads, 45 to 50 mph - 61 mpg, 55 to 65mph - 51 mpg, 70 to 80 mph - 44 mpg. I then pulled the cylinder head from my old 225K engine and confirmed my diagnosis of loose pistons.

I found a piston/rings kit on ebay for about $100. I have yet to measure the bores to see if they were pounded out of round. If so, boring to the next size may become necessary. Will I do that? Probably not, I have more pressing concerns.

So if your engine is ticking, just drive it. If it gnorks, get another engine, they are plentiful and inexpensive. Engine comes out through the top but it's tight. Save yourself some headaches and watch a couple youtube videos. If the car is rusty, don't bother, just get another one. Good luck!