Loud Tick/Knock during cold start on 4.8
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Loud Tick/Knock during cold start on 4.8
Hey guys Im trying to figure out what the deal is with my truck...its an 00 silvy with 152k in it...recently when I start it in the morning seein its been a little cooler, it will tick like a bastard...really loud and goes along with engine RPMs...depending how cold it is will determine how long it ticks...sometimes only a few seconds and sometimes almost a min...oil level is fine but it does use coolant...some of my other friends complain about the low coolant light coming on while idling...
the odd thing is usally when I change my oil it wont do it at all or just barly(and yes every 3k she gets done)...Im wondering if Im getting some coolant in there or something...but the oil level doesnt go up only coolant goes down...no leaks either...is anyone else dealing with this problem...I really hope its not expensive...I want to get rid of the truck soon but I dont want to sell it like this...
Sorry for the long thread...Thanks for your input guys!!!
the odd thing is usally when I change my oil it wont do it at all or just barly(and yes every 3k she gets done)...Im wondering if Im getting some coolant in there or something...but the oil level doesnt go up only coolant goes down...no leaks either...is anyone else dealing with this problem...I really hope its not expensive...I want to get rid of the truck soon but I dont want to sell it like this...
Sorry for the long thread...Thanks for your input guys!!!
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I have your same problem with tick/knock in the engine. Mine has been doing it for a year now. Still runs good. I haven't had a coolant leak either. As far as I know its the csk that is common on these engines.
#4
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You could be hearing a few different things...cold start piston slap is very common on the earlier GENIII engines, and it's nothing to worry about. Other possibilities include a lifter that is leaking down and making noise until it pumps up, or carbon build up on the valves that makes noise until it gets a little warm and the carbon softens up. You could try a Seafoam treatment and see if that helps, if not, I wouldn't really lose any sleep over it.
As for the coolant, the water pump to block gaskets are a common failure, and often they will leak so slowly that you won't visibly see it.
As for the coolant, the water pump to block gaskets are a common failure, and often they will leak so slowly that you won't visibly see it.
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thanks for all the info guys...I saw something a while back ago about the seafoam stuff...would just running a fuel treatment help or should I do the whole proceedure???...any other ways of fixing this...
#6
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The Seafoam is more effective than just a can of fuel treatment in the tank, as it is concentrated and directly injected into the intake. If carbon build up is the issue, than an induction service like Seafoam is the easiest fix. There are also pressurized treatments, like "BG" offers, but that requires a special tool and compressed air. To try and clean up the combustion chambers in a different manner would require cylinder head removal. Even if your noise is something other than carbon build up (such as piston slap or a lifter), it's still a good idea to perform an induction service once a year, or every 12K IMO.
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