93 Gxe with 261K miles. runs great and Im always on the road in here, but Lately Ive kinda gotten lazy on the maintanence. I noticed that I sometimes hear a clacking noise in my engine upon startup, and then it sometimes goes away after a few seconds. Then recently It starts to clack while im driving it for a few minutes. I checked the oil level and it was full. I have recently been using castrol 20W-50 for the summer months and its past due for an oil change. After the few minutes of clacking it just goes away. I dont know if the oil im using is to thick or flowing to slowly or what?

 

Sounds like engine knock. When was your knock sensor last changed? Out of all the typical 3rd gen issue I've never heard of the oil pump going out. These aren't GMs of the 90s. If you feel its that then get yourself an oil pressure gauge.

 

does it sound like the pistons are slapping? i know about 2 years ago on the really odd startup, i would get about 2 seconds of loud piston slapping in the morning. a year after that started my crankshaft started to go out and a year after that (this June) the engine started knocking bad constantly and that was it

but as said a oil pump going out is pretty uncommon

 

Man Way to go. Now you got him thinking his motor is going out. lol

 

could be nothing but thats the way mine went, from the odd piston slap, to the crank going out and wobbling and then loud knocking. and oddly enough 261,000 miles is 420,000km and mine went at 429,000km lol

 

Well I jus kno that somtimes I can start the car and I get nothing but tapping. But if I shut it off, and restart. It goes bak to normal. I was particulary concerned about the oil pump, because I used to own a 91 chevy baretta, with the same symptoms almost. the clacking at startup, then the pressure would jump bak to, normal, and it would do it on and off. It finially died on me. Thas why the max has me a little worried, if I can catch the problem early before its too late, ill b ok .

 

I have had a water pump do that on my 89 SE.

 

Oil pumps can absolutely go out on these cars. That is precisely why I'm currently not driving my turbo and looking at replacing my rod bearings. I count myself very lucky.
Also, 20-50 oil is absurdly unnecessary and I've seen cause issues in the VG.
The noise your hearing is the hydraulic lifters for certain. They wear too. But, I highly suggest you get a gauge and measure what's going on at startup and after warm up. Your symptoms sound exactly like mine when my oil pump went out. I replaced every lifter trying to fix, no luck. Better got on top of this and suggest maybe even parking the car.

 

Well i drove it today with no issues or anything at startup or driving. How difficult is it to relace the oil pump if necessary?

 

Like changing the timing belt but harder. You will have to disassemble the front of the engine as well as drop the y-pipe, crossmember, and oil pan. Not "difficult," but definately labor intensive. With as many miles as you have, may be in your best interest to do an engine swap. Maybe a rebuild? I've got brand new rings and freeze plugs! ;-)

 

20W-50 is way too heavy.

try a thinner oil...10w30 or even 5w30 and see if the noise goes away.
definitely get an oil pressure gauge on there and see what the numbers are.

chris...you got any spare freeze plugs? i think one of mine is leaking or something?

 

Yes sir, complete set of oem freeze plugs.

 

you selling them?

 

Ygm.

 

What are the freeze plugs for, And yes I will change my oil right away! How much does an oil pressure guage cost, and where do I hook it up to?

 

Freeze plugs are essentially plugs that are used to fill holes after casting steel or aluminum. Those openings are usually for accessing internal components. For example, you have two on the back of the VG upper intake manifold. Those provide access to the two vias butterflies.

You can hook an oil sensor up in place of the stock electric dummy light sensor. Or, there is an adaptor somewhere you can get which allows you to run both the stock pressure sensor and your aftermarket one. Be aware, the threads are different then what comes in most gauges. You don't want to strip threads on your oil filter housing or block (I say block becuase my setup utilizes the block port).

I suggest an Autometer electronic guage (pretty decent), that way you don't have to run oil lines into your cabin. Last I looked you can get one around $60-$80....been a while though.

 

Was at work and mobil forum won't let you edit. I'd add that freeze plugs fill the round openings on the block and have coolant running behind them through the block. They get the freeze plug name because if the coolant inside the block begins to freeze when sitting in the winter, the plugs will pop out and release the coolant as to protect the block from cracking.

 

+1 to the extra info I always like to learn about these cars.