Vitals: 2000 Olds GL1 Coupe, 3.4L, ABS.

Thought I got over the hump with problems on this car and this weekend a new one started. Drove for about 3 hours, almost all highway speeds (80mph). No issues. Stopped for about 2 hours and when I got back in the car started a ticking/knocking noise. Seems to be coming from the valve cover on the front side. It's sequential with the RPMs and is loudest just before shifting gears. Does look a little dry looking inside the cover from the oil fill cap, but oil level is good on the stick.

Amateur Mechanic friend wants to dive into the valve covers but that'll take the car down longer than I'd like. Just thought I'd see if anyone else had an idea.

 

Two guesses: Sticky lifter, or piston slap. I'd go with sticky lifter because a two hour wait doesn't seem like enough time to cool the engine enough to get obvious piston slap.

I'd try some of that oil additive that dissolves carbon to free the lifter. It may take a few hundred miles, though.

 

Iflow, is it a good idea to add oil additives to my oil changes? If so, what do you recommend?

 

I personally don't use the additives unless there is a real need, and I've tried other stuff first. For an oil leak, I'd rather fix the leak than plug it with an additive, unless the car was worn out and fixing it would be too expensive.
When you use the stop-leak, you can't tell what passages it will plug, so I only use it as a last resort.
As far as other additives, I just buy a good quality oil in the first place, and then I don't need any additives. A Rislone type additive won't hurt, but if you are using a quality oil in the first place, you don't really need it at each oil change, maybe once a year or so.
I have used Seafoam before, in the intake to clean carbon from the throttle body, but it can also be used in the oil. I will try that at my next oil change I think.

 

I would change the oil to Pennzoil Platinum. It is full synthetic and is the best cleaning oil on the market. Should be able to find a 5 qt container at walmart for $ 20. Run it for 4K and change. My guess is this will fix it if it is a sticky lifter

 

UPDATE: Tried the Seafoam which was fun but didn't change the noise. Also did an oil change just in case (always start with the easy fixes first). No success and the noise while getting quieter no longer sounds like the top of the motor, sounds like something is going to pound it's way out of the oil pan.

Taken the Alero to two mechanic shops and both are positive that it's a broken rod. Apparently the critical detail that I failed to mention is that the ticking never goes away, even after letting the car warm up (precluding a sticky lifter which usually goes away when the it gets warm enough). Both shops say that the aluminum blocks can't be successfully rebuilt and I'm being told by both shops to replace the engine.

Neither shop has dropped the oil pan to inspect from the bottom up. Both shops said its not worth the effort since the block can't be rebuilt.

Both shops have been in business for 20+ years and I trust both pretty well, but bro is convinced I'm getting taken to the cleaners. thoughts?

 

If it is a broken rod, you might have metal fragments/shavings in the oil filter. Cut it open and spread the filter media apart, if you see metal...that wasn't put there by you cutting it open, it's bad.

 

Well I think I would get a third opinion. The 3.4 never had and aluminum block. The 3.4 is know for ticking but usually goes away after warm up. If the noise was coming from under the valve cover I would have pulled the cover and looked for anything out of the norm. I really don't think you broke a rod. There is a lot of really nasty sounds when that happens. Could have a collapse lifter. Have you ever had the lower intake manifold gaskets replaced? I have seen the oil/coolant mixture gum up a lifter before. Let us know how it goes and what you find out. If you live anywhere near Phoenix let me know and I will come have a look at it.

 

I have about 130,000 miles on my wife’s car and I am having the same problem. The ticking get louder with RPM increase, but it can not be heard at idle. I have had a couple of my buddies listen to it with me and we were thinking either a lifter is sticking or a bearing on the crank has play. I will now in the next couple of days if it is a lifter, going to pull the valve cover on my days off. I did put sea foam in the engine (which I hate doing) to see if it would free something up but the car has not been driven enough to tell anything yet. I will let everyone know what I find and hopefully one of us will figure this out. In the mean time just turn the radio up and you will never hear it.