Need Help With Engine Knock
#1
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Join Date: Jan 2016
Posts: 19

S I have been dealing with this for a little while but it seems to be getting worse. I have a 1996 s10 blazer super base model and lately I have noticed that I have some sort of a knock. now this know is not constant, it is only at idle. you can hear it in park but its the worst in drive while being stopped. it tends to go away when I up the idle by two stepping or when I start driving. if I am stopped and do something to increase the load, such as turn the steering wheel the knock gets louder. I just was wondering if anyone out there is having the same issues I need help because I really don't want to start tearing it apart to find out what it is if there is someone out there that is having the same issue and has found a solution. I keep regular maintenance on the vehicle but keep in mind I have only had it for about 2 months. it has 107000 miles and just a side not when I got it the tranny fluid was pretty low but I don't think that is causing my issue cause it is full now. someone help me please....
#2
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Join Date: Jan 2016
Posts: 19

just a quick update. I found a tsb that says it could be caused by excessive oil consumption which kind of makes sense because I am due for an oil change. I will check my oil tomorrow when it is daylight and do an update. the tsb said this is caused by oil seals on the exhaust valves so I might look in to that soon. I would still like to hear your guys's opinions though. I will be doing an oil change probably next week and I will let you guys know if I find anything worth sharing or it it helps the problem at all.
#3
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,054

S I have been dealing with this for a little while but it seems to be getting worse. I have a 1996 s10 blazer super base model and lately I have noticed that I have some sort of a knock. now this know is not constant, it is only at idle. you can hear it in park but its the worst in drive while being stopped. it tends to go away when I up the idle by two stepping or when I start driving. if I am stopped and do something to increase the load, such as turn the steering wheel the knock gets louder. I just was wondering if anyone out there is having the same issues I need help because I really don't want to start tearing it apart to find out what it is if there is someone out there that is having the same issue and has found a solution. I keep regular maintenance on the vehicle but keep in mind I have only had it for about 2 months. it has 107000 miles and just a side not when I got it the tranny fluid was pretty low but I don't think that is causing my issue cause it is full now. someone help me please....

#4
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Join Date: Jan 2016
Posts: 19

Does it sound like this (video in post#1)? https://blazerforum.com/forum/2nd-ge...g-valve-87514/
#5
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,054

Mine also went away with increased RPM. Does noise start when the engine is warmed up, and is not present when the engine is cold? Post a video of yours.
Last edited by LesMyer; 01-28-2016 at 07:20 AM.
#6
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Join Date: Jan 2016
Posts: 19

Yes it starts when it's warm. I'll try to get a video later today if I have time.
#7
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,054

Is your SES light on? Does it work with key on/engine stopped? Mine was disconnected and the wire taped. Didn't notice that my SES light didn't work when buying the vehicle. Since then have figured out that excessive bearing clearance can whack out the misfire detection system and cause false misfire codes to be set.
Again, let me wait for the video. Also please describe oil pressure cold and hot, idle (in drive) when ticking and at 2500 RPM. I think you will find a big difference in oil pressure between when it is ticking at slow idle, and the RPM where it stops ticking.
#8
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Join Date: Jan 2016
Posts: 19

I'll wait for the video, but sounds like a lifter is collapsing at idle when engine is warm due to insufficient oil to it. Mine had excessive bearing clearances, presumably due to previous intake gaskets leaking coolant into the oil, and when warm and at slow idle it simply couldn't keep a lifter fed. I bought someone else's problem.
Is your SES light on? Does it work with key on/engine stopped? Mine was disconnected and the wire taped. Didn't notice that my SES light didn't work when buying the vehicle. Since then have figured out that excessive bearing clearance can whack out the misfire detection system and cause false misfire codes to be set.
Again, let me wait for the video. Also please describe oil pressure cold and hot, idle (in drive) when ticking and at 2500 RPM. I think you will find a big difference in oil pressure between when it is ticking at slow idle, and the RPM where it stops ticking.
Is your SES light on? Does it work with key on/engine stopped? Mine was disconnected and the wire taped. Didn't notice that my SES light didn't work when buying the vehicle. Since then have figured out that excessive bearing clearance can whack out the misfire detection system and cause false misfire codes to be set.
Again, let me wait for the video. Also please describe oil pressure cold and hot, idle (in drive) when ticking and at 2500 RPM. I think you will find a big difference in oil pressure between when it is ticking at slow idle, and the RPM where it stops ticking.
#10
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Join Date: Jan 2016
Posts: 19

So I'm going to school to be a diesel mechanic and we share a building with the auto tech and today the auto tech instructor took a look at my blazer and seems to think it's a thrust bearing because the harmonic balencer is moving a little bit. Can anyone agree with this judging by the sound in my video? If it is a thrust bearing I'm just gonna run it till she blows





