knocking I-6
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knocking I-6
I have a 1994 f150 with a I-6 that makes a slight knocking/tapping noise coming somewhere out of the motor. I noticed it recently, but thought it was somthing else until today after i changed the oil and listened to it run with the hood open. I can only hear the noise at idle, if i rev it up it doesnt go very much faster and it seems to dissaper, or the engine noise drowns it out, until i let off the gas. does anyone know what this is? i use mobil 1 10w30 synthetic oil and didnt hear it until recently.
thanks
thanks
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Joined: Jul 2005
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From: Lake Worth, Fla.
It could be the camshaft. They used to make the camshaft gear out of plastic and when it loses a tooth or two it will knock. If you remove the oil pan you might find some pieces of plastic in the sump.
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From: Black Hills South Dakota
If you can get a length of hose placed safely here and there while the engine's running, you can listen to the other end like a stethoscope. Might help pinpoint the location of the knock.
-Ed
-Ed
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From: Alma, KS
Fordtruck88 id check the cam cuz mine did the same thing and i thought the samething and now my motor is toast.
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I had the same problem a while back. It was especially loud on cold start up but quieted a lot real quick. Sounded like it came from the drivers side somewhere low in the distributor area. Tried the stethescope thing without success. By accident while changing again an Auto Junk lifetime alternator I found it was the air pump. The shaft would move in and out about a half inch. Donno if this is your problem but it could be and is an easy check. Sure had me going, the sound just did not come from the pump.
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on mine, i first noticed it after changing my oil and then running the truck with the hood open friday, it kinda sounded like a very slow chopping woodpecker, but i couldnt tell where it was coming from im the motor, it did this for like 5-10 minutes then i shut it off and restarted it a half hour later and it still did it. then the next morining i started i, drove it and i dint hear it, then i opened the hood and listened and the noise wasnt there anymore.
BTW- what does the broken-cam gear noise sound like and when does it happen.
thanks for the replies
BTW- what does the broken-cam gear noise sound like and when does it happen.
thanks for the replies
Mountain Pass
Joined: Sep 2004
Posts: 249
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From: AZ
My 1987 EFI 4.9 made more noise when I ran 10-30 oil, so I switched to 15-40 and it runs real quiet now except when cold the air pump knocks for a few minutes then it gets quiet. I guess I will break down ant buy a new one at autozone,it is the original. 123,000 miles and going strong.
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From: Houston TX
I was fixing to say check the fuel pump, but you should be
EFI with a 94... Using fram filters can cause startup problems.
Bad anti drainback valves... I use only motorcraft FL1A'a
for that reason on the sixes... I've had a light knock sometimes
on my 300. And it's fresh rebuilt. Sometimes it does it, mostly
not...I came to the conclusion it was probably the fuel pump
knocking. Thats where the noise centers at...Actually, it hasn't
done it much lately... On mine, you only heard it at idle, and
only when the engine was pretty warm, and had been driven a
good bit. I never heard it cold... This summer, haven't hardly
heard it at all...Been running real good...I'm still probably under
15k on the miles...MK
EFI with a 94... Using fram filters can cause startup problems.
Bad anti drainback valves... I use only motorcraft FL1A'a
for that reason on the sixes... I've had a light knock sometimes
on my 300. And it's fresh rebuilt. Sometimes it does it, mostly
not...I came to the conclusion it was probably the fuel pump
knocking. Thats where the noise centers at...Actually, it hasn't
done it much lately... On mine, you only heard it at idle, and
only when the engine was pretty warm, and had been driven a
good bit. I never heard it cold... This summer, haven't hardly
heard it at all...Been running real good...I'm still probably under
15k on the miles...MK
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A couple of weeks ago I changed my plugs after I noted some 'slighty' rough idle. They were pretty bad and needed it (40k+ miles on them). After about a week went by, I started to get a 'tick'. I swore up and down that the garage put cheap oil when I let them change it for my inspection. So I went down and got some 30 weight and a good fram filter and changed it again (only had about 1,000 miles on it). Sure enough, tick tick tick. Didn't help a bit. I was about to post on the board to ask what was wrong. Then my wife said "did you leave somthing loose when you were messin' around in there last week, that thing's tick'n". Well the next time something's wrong with the truck, I'm going to ask my wife...two loose spark plugs.
I saw a post a few months ago on just that topic. I put on a touch of blue lock-tight. We'll see how it holds up.
I saw a post a few months ago on just that topic. I put on a touch of blue lock-tight. We'll see how it holds up.
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