Jump to content

Recommended Posts

Posted

I own a 2006 sierra denali with the 6.0 gas. A few days ago I drove through a pretty deep puddle (I know the danger now) and immediately after my engine started knocking. It never stalled, never died or stumbled while in the water. I pulled my intake and it was full of water, filter was soaked. I let it dry while I worked, and let the filter sit in the sun for a bit. Put it all back together and on startup and at idle it did not knock. I could even raise the rpm's and it wouldn't. However once I got about 60 seconds into my drive it started again. Same thing today, it didn't do it on startup or revving at idle but once I put it in drive and went it came right back. I know the obvious answer everyone's gonna say is I bent a rod when I hydrolocked a cylinder, but wouldn't that make noise consistently? And raise with rpm's? Looking for if anyone knows any other possible reason as to why it's knocking or what I'm missing here

  • Like 1
Posted

Try it without the air filter and see if that helps. The water may have damaged it

Posted
16 hours ago, richard wysong said:

How's the oil look?

Oil is clean. Changed it a little bit before the incident and it's still clear clean looking oil, not milky.

  • Like 1
Posted (edited)

With the airbox soaked with water the water may have damaged the MAF sensor and screwing up the air/fuel mixture.  You don't have any codes? I would try and disconnect the battery for about 15min or longer to reset the computer as this could have screwed up the readings for the computer. Yeah definitely not hydrolocked. 

Edited by Silverado4x4
  • Like 1
Posted
15 hours ago, Silverado4x4 said:

With the airbox soaked with water the water may have damaged the MAF sensor and screwing up the air/fuel mixture.  You don't have any codes? I would try and disconnect the battery for about 15min or longer to reset the computer as this could have screwed up the readings for the computer. Yeah definitely not hydrolocked. 

 

Good thought! 

Posted

Is all the water out of the intake? Some are almost impossible to get all the water out. It will sit in there till revved. Then, boom.

Posted
On 6/13/2025 at 5:53 PM, Silverado4x4 said:

With the airbox soaked with water the water may have damaged the MAF sensor and screwing up the air/fuel mixture.  You don't have any codes? I would try and disconnect the battery for about 15min or longer to reset the computer as this could have screwed up the readings for the computer. Yeah definitely not hydrolocked. 

I do have codes like p300 and lean fuel on bank 1 but I had that before. No new codes. I pulled the tube off from the box to the throttle, should I pull the throttle and intake manifold too? Maybe waters stuck in the manifold and causing noise?

Posted
On 6/13/2025 at 10:14 AM, richard wysong said:

Try it without the air filter and see if that helps. The water may have damaged it

Without the filter it makes the same noise

Posted
On 6/14/2025 at 8:55 PM, PunchT37 said:

Is all the water out of the intake? Some are almost impossible to get all the water out. It will sit in there till revved. Then, boom.

Up until the throttle yes, I didn't go further than that. Would it get past the throttle and stay there?

Posted
40 minutes ago, Chrisgreenm said:

Up until the throttle yes, I didn't go further than that. Would it get past the throttle and stay there?

On many modern engines, once a liquid gets in the intake, it`s a good idea to change it. You can`t just pour it out. It will stay in the bottom of the long runners. Then, with enough air velocity, it will make it to the cylinder. Then, a bent or thrown rod. Maybe not your particular intake but, something to think about. I would at least pull it and see if water is in it, and if you can get it all out.

Posted
On 6/16/2025 at 9:17 AM, PunchT37 said:

On many modern engines, once a liquid gets in the intake, it`s a good idea to change it. You can`t just pour it out. It will stay in the bottom of the long runners. Then, with enough air velocity, it will make it to the cylinder. Then, a bent or thrown rod. Maybe not your particular intake but, something to think about. I would at least pull it and see if water is in it, and if you can get it all out.

So I finally got around to pulling the manifold. There was a decent bit of water in there mixed with oil. Got it all out and dried it, reinstalled and the noise is still there. 

Posted

Anyone have any ideas what could be rattling around? I've checked it over and over and I don't see anything. Maybe it warped something like my exhaust? Did hit the puddle right after coming off the highway so it was definitely hot

Posted

If it`s not the engine, then maybe the cat core is broken and rattling around. The cat is usually very hot and driving through cold water shocks the ****** out of it.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Latest Articles

  • Posts

    • That's interesting, I assume that would add to the cost of the oil but also I was forgetting to bring up the issue of the low tension rings allowing more oil past which in turn forces the cats to have more oil additives pass through them that wouldn't otherwise so they are creating that problem and of course its all in the name of fuel economy. Mind you the other issue would be the lack of additives that fight the formation of carbon within the piston ring grooves which turn the engine into an oil burner and with in this GM forums case is your average off the shelf Dexos licensed oil, meanwhile the other off the shelf oil being Valvoline's R&P isn't licensed and the only one that is which is that certain Mobil oil that came out recently ( its not even being marketed in Canada ) and only a fraction of vehicle owners are going to be using it out of all the other oils on the shelf or the quickie lube bay that meet the Dexos spec by way of actual licensing.    Also I suspect that its an easy excuse to pool the non turbo DI engines in with the turbo DI engines and design the oil to not have LSPI issues in the most demanding engines and short change the naturally aspirated DI by not offering a higher concentration of additive package they could handle and still not be at risk of LSPI.    I wonder if Amsoil flipped the switch just lately and did whatever packaging designation at the same time as I wonder what oil formulation I would have bought in May, of course I don't know when it was packaged at the factory vs how long it was in storage at the Edmonton warehouse. I know its been said at least in the past that the big players switch over to a reformulated oil but the packaging has not changed until they make that move as well so there is that cross over time where its a new formulation in a predated formula marked package. 
    • Hmm. A real reason to not just use the odometer to determine OCI?    
    • Sad thing is that this doesn't have to be the case. LSPI can be solved without a reduction in TBN. Swap Ca for Mg.  Cats are not a issue if the OEM can get a ring and valve guide seal even at SN levels of SAPS. Dizzy is purring like a kitten with a bowl of warm milk. 200K of Full SAPS oil and zero detonation issues and nice a clean inside and out. This shouldn't be an issue. It isn't 1920.    Tell ya what AMSOIL SS is excellent at, internal cleanliness. The new formula is even a step up from their already outstanding cleanliness levels. Can't say the OEM offering is quite that clean. There marketing suggest the SS is cleaner.     That is the only defense with at shelf oil. Nothing wrong with them if you ignore the marketing and OEM 'recommended' OCI and use a thimble full of common sense. 😉 You go sir. 
    • I started with a folding cover by BAK PAC on my 2500. It went bad after close to 5 years. Bent and vinyl coming loose. Contacted BAK and they gave me a very good discount on a Revolver. Had it a number of years. Mostly outdoor storage. Some garage storage. Vinyl started to come loose. Still under warranty so they replaced to cover. Sold the 2500, bought the 1500 and got another revolver for it. Had it a couple years now and no issues. I store it indoors. Got a bit of discount when buying it as well. If you are seeing problems, contact BAK or real truck and let them know. Customer service was pretty good. But I think they changed their warranty.
    • I agree, there is no one answer fits all as every rig is different, one may be pulling some little aluminum fishing boat while another is towing a monstrosity that weighs a lot and hopefully the owner if the rig has some prior experience to know what drive mode they should choose.    It also struck me and this is from watching a few of those boat ramp escapades videos in the past, Ford being one of the vehicles that has the auto front axle hubs and sure enough its found out that one hub has crapped out and won't engage and may not have manual hubs to even select on both sides so they are on the boat ramp stuck with no four wheel drive and spinning .... they flat out need a tow to get up the ramp and deal with the vehicles new found issues. That can happen to all brands of pickup, finding out either four wheel drive or 4 low isn't working right at the time its needed it to work as some electronic crap has failed. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...