Ok...
ANYTIME you hear knocking in the engine, it's an EXTREMELY bad sign.
Here's a few quick steps, feel free to email me or VM if you have any questions...
Change the oil, the first thing to look for is metal flakes in the drained oil, and inside of the oil filter.
Check to see if the oil looks "milky", especially under the oil filler cap. This is a sign of coolant in the oil, probably caused by a ruptured head gasket.
Preform a compression test on all four cylinders. You can rent the gauge from Autozone, Advanced Auto... This will show the compression or each cylinder, which can 1. prove a bad head gasket 2. show piston and or piston ring wear. All four cylinders should be within 10% of each other in PSI 3. Show possibility of burnt or bent valves. <<Can cause noise, misfire, strange smells, bad gas mileage, stalling... Burnt valves can be really noisy.
The stalling can be caused from SEVERAL reasons. Do you notice any difference in gas mileage? Any oil on the spark plugs or on the wires? Maybe a computer error? Have you had a CEL? Bad fuel pump? Dirty air filter? There really are several reasons a car can stall. I'd buy seafoam and run the treatment. 1/3 can in crank case, 1/3 can in gas tank, 1/3 can in any vacuum line (this dumps it right on the pistons, and will clean and gunk out that might build up in the combustion chamber and valves.)
Helicopter noise can be due to... Bad steering rack, tie rod ball joints, worn CV axles (if it's FWD), worn wheel bearings, bent/unbalanced rims, damaged control arm bushings... Jack up one side, grab the wheel and check for any movement, there should be NONE. Do the same to the other side. Look underneath at the CV axle boots, check for tears and grease splatter.
Slow accelerating is a broad problem too. Again, have a compression test preformed, it could be bad valves. Check the air filter, filthy air filters can restrict air flow, causing loss in performance. Remove and clean the throttle body. It may be full of carbon and having trouble opening and closing. Spark plugs, DON'T buy the cheap Autolites at Walmart, get OEM.
Contact me if you need any help.
