When I first start my car ( when the engine's cold), It knocks for a couple seconds (like a rod knocking), until the oil press light goes off.

How long is it supposed to take to build pressure? Could my oil pump be getting weak? I really dont like it.

I keep a reuglar oil change w/ 10w-30 semi syn., and never let it get below a half quart.

Or is it just normal.

Jordan

 

It's not normal. Your bottom end has one or more bearings worn to the point where metal touches metal until oil pressure builds. It's these clearances that need to be tight to build pressure quick in the first place.

Now, it may be fatal, it may not. I've known Toyota engines to run for years with spun bearings. (I've personally had two, one was turbo.) Others will last a few days only. Fact is, you have a problem and it will get worse over time. How much worse, who knows... If you are lucky, you will only get the noise at start-up and never hear it once pressure builds. If this is your case, this is the first stage of a spun bearing and not fatal. It may eventually start to knock when cruising or idle. This is the second step and a sure sign of impending doom. As the damage progresses, the knocking gets louder and louder and your oil light may turn on at idle. The bearing clearances are so loose that the engine can't even build oil pressure. The oil just slips thru the bearings unrestricted. At this point the cams are not getting the lubrication they need and will start to chew up their bearing journals, or turn colors from the heat. This will send aluminum chunks into the oil supply which should all end up in the oil filter, clogging it up in short order. In turn the motor is further starved for oil and a siezure is sure to follow soon after.

This is all of course *IF* the spun rod bearing doesn't send a broken rod through the side of your engine block and spilling it's guts all over the street. This is never pretty because not only is it a catastrophic failure, it will leave you stranded unexpectedly.

Of course I'm not trying to scare you into not driving your car. Just keep an ear on the noises it makes. If you ever hear it while driving, there's a problem. At that point start shopping for a mechanic that will rebuild your bottom end. Another option is to find a used engine (they are dirt cheap nowadays) and swap it with yours.

Also, try some 10-40. The thicker weight oil will build up your pressure faster between those now-large clearances. It will slow the progressive damage to the car at start-up.

Good luck.

 

my car has been doing that on startup for 4+ months now

 

Thanks for the imput. I didnt realize it could be a bearing. The car has been babied since it was new, and always had regular oil changes w/ mobil1 syn, since new, until I got it a couple months ago and put castrol semi syn.

Maybe I should try a non synthetic oil, or a "high mileage oil" The car has 130K mi. One mechanic told me that you shouldnt use synthetic oils in brand new, or high milage engines, but I know thats a debatable subject.

I does kind of make sense, bc synthetics are more slipery, and can easily "slip" through the bearings.......I dont know.

But what I dont understand is what would cause a bearing problem in a well maitained, well built, factory 2jz-ge?

Jordan

 

It could likely just be a worn bearing, not spun.
Usually the rod bearings wear out twice as fast as the main bearings, I may take my oil pan off this winter and replace the rod bearings only.
The 10-30 oil is pretty weak on an older motor, the 10-40 is a great way to go and will even add some compression. These motors use chrome rings that don't have much tension, and the thicker oil will help.

 

Before anything do the "Top Engine Clean" aka TEC Svc first. It may just be carbonized combustion chamber. May be more serious, but you need to eliminate easy stuff first... Good luck.

 

Or if your like me and dont care because you have another engine you can install if needed laying around, just turn the radio up when u start the car up

 

I am having a problem like yours. How is your top end? My power band is weak.