Engine rattling noise at light throttle, any ideas (1 Viewer)

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Has anyone heard of this engine noise before? Happens when driving and using the light throttle. Valve Train noise? My engine does have a top-end tick but this noise is aside from that. Sounds like a Tamborine to me...
 
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Looks like pinging, to much advanced? Bad/old gas? Carbon build up?
Only at hot engine? At what engine speed? 1000-1200rpm?

Do another test. Park the car next to the wall on the side of the exhaust, shift on Drive, hold the brake and slightly gas pedal

Too much questions☺️
 
Joined
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Dallas, Tx
Looks like pinging, to much advanced? Bad/old gas? Carbon build up?
Only at hot engine? At what engine speed? 1000-1200rpm?

Do another test. Park the car next to the wall on the side of the exhaust, shift on Drive, hold the brake and slightly gas pedal

Too much questions☺️
I did my timing a while back and set it to OEM spec for America. I do ping put that’s going balls out getting to highway speed. This is when driving and feathering the throttle at speeds greater than 10 miles an hour. Sounds more like chain slap or valve lash. I’ll try your test though!
 
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I did my timing a while back and set it to OEM spec for America. I do ping put that’s going balls out getting to highway speed. This is when driving and feathering the throttle at speeds greater than 10 miles an hour. Sounds more like chain slap or valve lash. I’ll try your test though!
Ever figure this one out? My 93 makes a rattling noise when under very light load/throttle. Higher octane doesn’t help and I’m set at factory spec timing so I hesitate to believe it is pinging…

I am beginning to wonder if it’s the timing chain or tensioner that is slightly slack when under very light load.

Curious what you found?

Josh
 
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Ever figure this one out? My 93 makes a rattling noise when under very light load/throttle. Higher octane doesn’t help and I’m set at factory spec timing so I hesitate to believe it is pinging…

I am beginning to wonder if it’s the timing chain or tensioner that is slightly slack when under very light load.

Curious what you found?

Josh
I think you are on the right path, I actually sold that rig and bought another and it makes the same damn noise 😂
 
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i cant see the video in the 1st post for whatever reason however the description sounds like light pinging / detonation - i tried the high octane fuels as well and no difference however on LPG no rattle at all

how many km/miles on the engine? does it burn oil? when were the injectors last serviced - they could be leaking

mine would on occasion make a rattle at light throttle in hot weather only before the HG went and since I did the HG doesnt do it any more with timing set at 3deg btdc plus I serviced the injectors as well

Step on the gas a little more and it would go away.

Valve stem seals were also past their use by date when the HG went which was the cause of my oil consumption however there wasnt much carbon buildup on the piston tops and whatever was there was cleaned off with CRC easily
I suspect in my case it was the oil seeping / misting into the combustion chamber that caused it.
 
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i cant see the video in the 1st post for whatever reason however the description sounds like light pinging / detonation - i tried the high octane fuels as well and no difference however on LPG no rattle at all

how many km/miles on the engine? does it burn oil? when were the injectors last serviced - they could be leaking

mine would on occasion make a rattle at light throttle in hot weather only before the HG went and since I did the HG doesnt do it any more with timing set at 3deg btdc plus I serviced the injectors as well

Step on the gas a little more and it would go away.

Valve stem seals were also past their use by date when the HG went which was the cause of my oil consumption however there wasnt much carbon buildup on the piston tops and whatever was there was cleaned off with CRC easily
I suspect in my case it was the oil seeping / misting into the combustion chamber that caused it.
Yeah, I burn about a quart every 600 miles. 196,000 miles and the head has never been touched to my knowledge (nor the injectors). It’s time for a top end rebuild for sure.

I concur, once given more throttle, the noise goes away. Makes me think an injector could be spitting as you mentioned? At this point I need to just get the work done but always hard to give the truck up for a few weeks :)
 

mdawg

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Yeah, I burn about a quart every 600 miles. 196,000 miles and the head has never been touched to my knowledge (nor the injectors). It’s time for a top end rebuild for sure.

I concur, once given more throttle, the noise goes away. Makes me think an injector could be spitting as you mentioned? At this point I need to just get the work done but always hard to give the truck up for a few weeks :)
I had the exact same issue on my ‘97 at 282k. Premium fuel helped some, but not 100%. I was burning about 1 qt every 400 miles, so I pulled the head and had a valve job done, along with injector reconditioning by WitchHunter and a new fuel filter; everything else done was new seals/gaskets/hoses. After reassembly and setting timing to factory spec, no more oil consumption and no more octane ping at light throttle.
 
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I had the exact same issue on my ‘97 at 282k. Premium fuel helped some, but not 100%. I was burning about 1 qt every 400 miles, so I pulled the head and had a valve job done, along with injector reconditioning by WitchHunter and a new fuel filter; everything else done was new seals/gaskets/hoses. After reassembly and setting timing to factory spec, no more oil consumption and no more octane ping at light throttle.
Sounds like I just need to bite the bullet and just get it done!
 
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Started mine up for the first time in a year. slight tick or rattle on slight acceleration. I’ll post the video to YT and link it.

You can hear it between 15 and 21 seconds.
 
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Mine also did the same thing before I did the head gasket. Valve stem seals were leaking and lots of carbon on the pistons. Noise went away after the job was completed. I had the injectors rebuilt at RC engineering. Truck currently has 230k and runs perfect!
 
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I've chased this noise for two years, seems like the next option is R&R the head and and that might take care of it.
So far I have done:
Plugs
Plugs grommets
Valve cover gasket
Plug wires
Injectors
Throttle body gasket
Both intake gaskets
Fuel filter
Maybe one or two more things with no luck.

But it runs fine I just hate the noise. It's got 305k on it and burns a quart about every 600 miles but I don't really worry about it anymore.
 

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