I just flush my engine yesterday and upgrade my oil to castrol synthetics (sp). Actually i flush my engine,which was very very black and muddy ( i think the dealer didn't even change my oil when i bought the car or used low quality ones ) and had an emission clean because i did notice some slow excelaration and low mpg, finally change my filter and got a full wash.

I watch and made sure i got about 5qt (about 4.75 was put in) of the oil, inspected the oil and air filter when it was open, the shop did the work with me right there so i saw everything, they seem to do everything right.

now excelration is better, but i notice the oil seem low,is it normal to appear low after switching from conventional to synthec? and there is a slight knocking when i accelerate but it goes away and it don't happen everytime. could this be my engine adjusting to the newer oil?

 

when you do an oil change, after you start the car, give it a min of run time, then shut her off, wait about 3min for all the oil to go back into the pan, and recheck, you have to remember that the oil filter accounts for some oil also if you didnt add any into the filter on the change. dipstick should be inbetween the markings, better to be more towards the top than bottom for most people.

 

what do you mean when you say you had an emission clean sorry im a newbie when it comes to these things

 

Basically it clean your fuel system. Place like jiffy lube, superlube and such offer this service. Cost about 50$. remove clog and debris, and actually does help a little in performance and mpg. I notice my car is smoother and and acceleration feel sharper.

It isn't something you have to do, just for me, it gives me peace of mind.

 

Could be from some build up being cleaned out???(Knocking) I'd check/top-off the oil, its normal for some cars (esp. high mileage ones) to consume oil for the first few uses of synthetic oil.

 

Sometimes when you drain out the flushed fluids theres still some of the flush chemical stuff in the engine. There will be some sitting on top of the cams bolts, corners, and other paces where there is level spot and oil cannot drip down. Those leftover will ruin your engine quickly , making the new oil you just put in less effective.

I rather not use any of those flush things. Just use synthetic over 6 month and your internal will be clean. since synthetic have a more/or better detergent agent.

I used to build my SR20det on my s14 . I drove it for about 4months using reg motor oil right after the rebuild . Then when I install new cams, there were a little sludge build up over and around the cam area. Right after that I use synthetic and few months later i open it back up to install some rocker arm stopper and the whole head area looks brand new.