'98 Civic engine knock after alternator dies?! Need Help!

[TheBlackRabbit]

I have a '98 civic EX coupe with around 160,000 miles. The car was mechanically running perfectly fine ever since I have had it, only issues were minor such as window motors, etc.

The oil was changed with it's usual 5-30 full synthetic and a mobil 1 oil filter less than 200 miles ago. It was completely full of oil this whole time.

I was driving at about 45 mph when the car suddenly dies and I was barely able to coast into a safe spot off of the road. Now that I think about it, the car engine did seem to start running substantially louder (kinda like you are really low on oil when the engine just seems a little bit "ticky"), but this was only for a few seconds before the car died.

The car wouldn't even try to start. I tried hitting the alternator with a metal rod I had in the back. This made the car start to turn over or almost start, but not quite.

Last night I had the alternator changed. The car cranked right up. The engine makes a horrible knocking noise like there is metal in the engine synced perfectly to the RPM's. At low RPM's it is a knock, at high RPM's it is a grind.

What could it be and why???

Edit: The car has no check engine codes

 

[Raizinman]

You hit the alternator with a metal rod?

Are you sure it was the alternator and not the starter? Not quite sure why you would do this but if you knocked off a plug wire, or damaged a sensor or pretty much other things too, this could be your problem. I’m not aware of any possible scenario where you can hit the alternator with a metal rod and then the car will then start to turn over?? Are you sure you mean alternator and not starter? Is this how you treat your car when it malfunctions? Just get out the metal rod you happened to have in back.

 

[TheBlackRabbit]

No, someone told me to try it and I was stranded so I said why not, its probably bad anyway. here are some links:

http://answers.yahoo.com/question/index?qid=20081215222008AAqEgpY

http://www.jeepforum.com/forum/f11/tapping-my-alternator-hammer-366042/

It wasn't like I did damage to anything else, the only part I made contact with was the alternator. And yes I am sure it was the alternator. Not saying it was right to hit it, but I hit it with a lug wrench I had in the trunk and it started to turn over briefly after I did that.

 

[CurseTheSky]

A bad starter wouldn't cause the engine to stop running spontaneously... but I've never heard of hitting an alternator to get it working again. That sometimes works with a starter if the bendix is stuck.

What do the oil and coolant look like right now? Is the oil still reading full on the stick? Is the coolant full / normal looking, or is it murky, milky, or frothy?

 

[TheBlackRabbit]

Well, I was stranded and someone told me to try it so I hit it with a lug wrench. There is some people saying on message boards that occasionally it can get it to start up again. It definitely was the alternator that I hit.

The oil looks normal and is completely topped off at the right level. The coolant level is normal and looks normal as well.

 

[LTC8K6]

You need to narrow down the location of the sound.

 

[Raizinman]

If the knock sound is synced to the engine RPM then you are probably looking at some internal engine repairs such as bearings. How many miles on the odometer? Are you sure the oil change was done correctly with the correct filter? Did you do it or was it a Jiffy Lube type shop? Does the knock noise get louder after a minute or two or does it get quieter? Did you have any other service done at the time of the oil change? Perhaps anti-freeze flush or change? Like someone mentioned prior, see if you can locate better where the knock is coming from. With the engine running, remove the oil fill cap and see if noise is now louder?

 

[hanoverphist]

what kind of temps was it running at the time? did it get really hot as well?

the alternator is between the engine and firewall, covered with hoses and crap. id have not tried to hit it, but whatever.

once you rule out things like oil/ coolant color and status, you need to start looking at the moving parts left. the distributor may have a slipping gear (unlikely), the cam or main shaft may have slipped bearings, or it could be your power steering pump/ ac compressor/ alternator bearings freezing up. an accessory that is bound up inside will drag your engine down enough to kill it.

 

[SuperSix]

What does the oil look like?

 

[LiuKangBakinPie]

Check your timing; also check the octane rating of the fuel you're using. The owner's manual can tell you whether your vehicle needs regular unleaded or premium gasoline.

 

[natto fire]

Any kind of squeal from the belt area of the engine? (could be bearings in one of the accessories) Can you get access to a stethoscope? (they make them for just auto use, but you can use a regular one as well)

I am confused as far as your initial symptom. After you got the car safely off the road and tried to restart it, were there any clicks or other noise, or just dead? After hitting the alternator (only heard of doing this with starters myself) it turned over but failed to start, how did the cranking sound? Replacing the alternator made it start up fine?

Did you replace the alternator yourself, and was it tested?

As for the noise, is there any kind of performance difference? Does it ever sound like a higher pitched whirring, or is it always more of a knock/slapping sound? It sounds like you might have spun a bearing, but hard to say for sure.

Do you have an automatic or a manual transmission? As pointed out above, you need to find out where the sound is coming from and if it is only tied to engine RPM, or vehicle speed as well.