You may have a Vacuum leaks that may cause the fuel trim to run rich as the computer tries to compensate for the extra air being sucked into the engine through the leak. Check at the exhaust connection to the engine for the loud noise.
With 161000 miles you need a total tune up. Add dry gas to the tank to eliminate some of the moisture. Remove the throttle body and use carbureted fluid to clear any gum out. If you have engine light please mention it so we can help how to retrieve the code. I believe this will save you lot of money compare to the cost of new engine/trans/transfer case and every related computer and wiring harness, this is same Jack said.
Fix the loud noise and total tune up will increase power and fuel mileage.
A new engine costs thousands of dollars, so all other options should be exhausted first.
Make sure your car can support any upgrades you plan on installing. If your new engine will not be a stock engine (also called a "crate" engine) then you need to make sure your ideal upgrade is feasible. The best way to do this is to contact the dealer for "mounting kits" or "upgrade kits" for your car model and desired engine. If mounting kits are not available, chances are you'll need to talk to an auto-body specialist about doing a custom upgrade. Custom engine installations are often very expensive.
Order from a dealer or directly from the manufacturer. Go to a car dealer specializing in your car brand, Ordering from a source other than a reputable dealer or manufacturer can lead to problems; you may end up with a refurbished engine rather than a true, brand new, factory-produced engine.
This may be costly.
Wednesday, April 28th, 2010 AT 2:29 AM