Q: Hello Noe, I was wondering how much you would estimate a Timing Chain Guide Replacement on a 2004 sentra spec v?

I live in WI & it was cold out. My engine started making a knocking noise. I do have a moderate oil leak so I figured i was just low. Then the knocking got really loud and went faster or slower with acceleration or slowing. i filled up the oil and the knocking quieted but is still loud. From research, I am guessing it is the Timing Chain Guide and it needs to be replaced. I know the parts aren't too expensive but it is labor intensive due to its location. I am debating whether I want to repair it (in a shop) or give up on this car. Up until now, I haven't had many problems: brake calipers that freeze up, some exhaust issues, camshaft/crankshaft sensors, an oil leak, and a power steering leak. What would estimate the repair costs to be and I read there are other things that I should replace since the engine with be out. Possibly: rear timing chain cover gasket, oil strainer screen, oil pan, pan gasket & mount, water pump, timing chain tensioner. Thank you for help!

My car has 160000 miles.
My car has a manual transmission.