i park my car on a slight incline. in the morning when i go to start it , i get a slight knocking noise for a few seconds then it dissapears,the car drives fine,.all day it is fine. next morning same thing.i think its something to do with oil pick up maybe. its a v8 4.6l mustang. any ideas guys/ gals?
2007-01-25 23:58:49 · 20 answers · asked by nixopaxo 2 in Cars & Transportation ➔ Other - Cars & Transportation
It's going to be a lazy oil pump or bad circulation of oil caused by sludge etc. You may cure this by changing the oil and using flushing oil in between the change
2007-01-26 00:03:04 · answer #1 · answered by Sir Sidney Snot 6 · 1⤊ 0⤋
A lot of people are saying it is something with your valves and lifters, which would most likely sound like a very crisp tapping, not a knocking. My old F-150 (5.0L) had the very same knocking as your Mustang and I always figured it was a worn wrist pin or connecting rod that just wasn't getting enough oil when it was cold. After the oil circulated and the parts expanded slightly as the engine warmed up, the knocking went away. Just don't forget the effects of thermal expansion as the engine warms up. (My truck had 140,000 miles on it at the time, about the time for a 5.0L to start acting cranky.)
2007-01-26 08:42:52 · answer #2 · answered by djm3452004 2 · 0⤊ 0⤋
Hydraulic tappets/valves, the oil drains out of the galleries overnight, come morning when you start up, the tappets rattle until oil pressure builds up after a few seconds then you will find everything ok. It used to happen with my Rover V8. One very important thing to bear in mind, only use the correct engine oil, if you use anything thicker the cam followers will not be able to release from the cam properly because the oil won`t be able to drain away fast enough resulting in a worn out cam, that`ll make a noise.
2007-01-26 08:25:03 · answer #3 · answered by Spanner 6 · 1⤊ 0⤋
Hi yes you have hydraulic lifters and the oil pressure is low so I guess that either you are low on oil, need an oil change, or using the wrong oil.
If you leave it you may have the opportunity to replace loads of bits, however some do do it when the engine is a bit worn.
2007-01-26 08:56:43 · answer #4 · answered by rinfrance 4 · 0⤊ 0⤋
Just a theory, but because you are parked on an incline, when you start the motor, it might take the oil slightly longer to reach the injectors, causing the engine to knock because the cylinders are not yet fully lubricated. Try parking on a flat surface and see if the same thing occurs. It could also be a mild form of "vapor lock."
2007-01-26 08:04:59 · answer #5 · answered by Anonymous · 1⤊ 2⤋
Those tritons make some timing chain and tensioner racket till the oil press comes up. You may have some wear in the timing set.
2007-01-26 08:54:53 · answer #6 · answered by done wrenching 7 · 0⤊ 0⤋
try parking the other way round so the the oil sits at the other end of the engine
2007-01-27 22:03:27 · answer #7 · answered by dave h 1 · 0⤊ 0⤋
could be the hydraulic tappets taking a little time to lubricate, had the same thing myself with a Vauxhall, sounded like a diesel when first started but after a few seconds it sounded fine
2007-01-26 08:09:16 · answer #8 · answered by Anonymous · 3⤊ 0⤋
Probably is the oil getting pumped up and lubing the engine to begin-with.
2007-01-26 08:06:57 · answer #9 · answered by CRZYDV 2 · 0⤊ 0⤋
Silly answer but have you checked the oil level?
RoyS
2007-01-26 08:06:27 · answer #10 · answered by Roy S 5 · 0⤊ 0⤋