Help Me Diagnose My Car

I’m hoping someone here can help diagnose an odd car problem.

Subject is a 2000 Saturn LS1 with about 65,000 miles. It was just in to the dealer three weeks ago for the 63,000 mile service. The only thing noted during the service was that there is some valve ticking. The dealer said it’s probably nothing to worry about, but should bring the car back if it gets worse.

The car was running fine. The valve ticking may have gotten slightly louder, but I thought it was just because it was pointed out to me and I’m now paying more attention to it. Yesterday we were waiting at a light when the engine suddenly started running extremely rough. After a few miles the check engine light came on.

We brought the car back to the dealer. However, the service department is closed until Monday morning. Anyone care to venture a guess as to what’s the problem? Is the valve noise a red herring?

Give me a little more information…

Were you able to drive it to the dealership or did it have to be towed? Does the car have an oil pressure gage? Were there any fluids under the car? When did the original noise occur, all the time, when accelerating?


Duplicate post.

Car was driveable. However, it is not running well and we felt that driving it as little as possible seemed prudent. There isn’t an oil pressure guage. I didn’t see any fluid leaks. I did check the oil. It’s at the recommended level and does look clean. The dealer did notice the ticking right away and thought an oil change would fix it. It didn’t.

The ticking is most obvious at idle. You really can’t hear it once the engine is up to 2000 rmp or so.

Where do you live?

Near San Jose, CA. The dealer is supposed to be looking at it now. But, I haven’t heard anything.

It really could be anything, but due to the timing of recent work, I’d look at the vacuum system. Something may have been knocked loose.

Ok, thought you maybe lived where it’s -20 right now. I’m thinking fuel pump or some kind of fuel problem. Wouldn’t have anything to do with the valve ticking, but could be the cause.

Let us know what you find out!

Yep, sounds like a vacuum line came loose. Or a faulty emission control device.

I’ll go with the EGR vacuum circuit 'till we hear back from the shop.

Anyone else want to take any guesses?

Spark plugs! #2 was not firing at all and the others were marginal. The actual repair was fairly inexpensive. However, they spent several hours diagnosing the problem and this cost some serious money. It turns out both the recent work and valve ticking were red herrings.

I never would have never thought a spark plug could fail so suddenly, but clearly they can.

Many thanks to all who contributed their thoughts.

Sounds fishy that they took so long to diagnose the problem. If the engine light was on it should have coded something like “cylinder 1, insufficient spark” or some such verbage. As long as the engine light came on they could have simply plugged in the computer and found the problem right away, not sure what the confusion on their part was.
Any Thoughts?
Did they tell you why it wasn’t firing? Loose wire (possibly their fault from earlier work), bad plug, bad coil pack, bad spark plug wire…?

The dealer did mention there was a code that #2 was misfiring and said the time was spent figuring out why. The spark plug was fairly far down the list of things to check. They stated that all the plugs were fouled with #2 being by far the worst. They did insist that they save the old spark plugs for me to inspect when I pick up the car.

The plugs were changed at about 40,000 miles. It’s not clear to me why they would need changing again.