99 3.0 valve chatter under load

[vpetersen]

My 99 3.0 has a ticking / chatter coming from under the driver side valve cover. When I pop the hood and listen at idle I can just hear it under the valve cover. Then while driving, it chatters louder the more load I put on it. I'm thinking of taking off the valve cover and inspecting for any obvious damaged/worn parts. The problem is, I'm not a mechanic and might not recognize what is wrong if its not obvious. I am mechanically inclined and do pretty much all my own work, so thats not an issue. Any ideas for what I should be looking for would be a big help. Thanks.

 

[Sasquatch_Ryda]

If you down shift and let the engine rev a bit when it is under load does it go away?

If so, sound more like pre-ignition (pinging)....which these 3.0L's are common for.

 

[vpetersen]

yeah, if I'm going down hill and the engine is reving from engine braking, the noise goes away. If I accelerate to say 4k rpm it will chatter up to the point that I let off the gas, then noise goes away.

 

[Froggmann]

That sounds like pinging.

 

[stmitch]

These 3.0's are known for pinging, or detonation. The cumbustion chambers are kind of rough castings, which allows carbon deposits to build up. Running low octane gasoline can worsen the issue. I'd recommend using some sea foam or other de-carbonizer, and after that try using a higher octane fuel. If those don't eliminate your noise, then you could have a valvetrain issue, but start with the cheap easy stuff first.

 

[vpetersen]

ok, so I'm onboard with it possible being pinging. I did seafoam the engine about 2 weeks ago, and the noise did seam to lessen a bit, but has since returned. I'm thinking of seafoaming again. What are some other things I could do? Would a clogged pcv valve contribute the the noise? I was thinking of changing pcv valve and checking/cleaning/replacing egr. Also replacing the fuel filter, just for the hell of it.

After all those things, if the noise persists, and if it is pinging and not a valve train problem, what would be wrong with just living with it? Will it cause further damage if not corrected?

 

[Froggmann]

If your truck is flex fuel, run several tanks of E-85 through it.

 

[TomB1269]

When you seafoamed it your talking about the upper intake manifold, correct. It should have smoked like hell if you followed the directions (I let mine sit for 10 minutes and my engine is usually not at full temp, warmed so the fluid can soak in vs evaporate). PS the best location IMO is just behind the throttle body pull the small vacuum line and plumb it thru there. It has the best possibility of getting the fuild to each cylinder evenly.
PS: You may need a plug change afterwards if it should dump a ton of crud.

 

[vpetersen]

I did another seafoaming today, through the vacum hose off the brake booster as per the instructions on the bottle. Engine does run better, as always after seafoaming. However, the chatter is still there. I also bought a 180 degree thermostat because I was told it does wonders for pinging. I didn't install it yet, probably tomorrow. I dont think the thermo with fix the problem, because my noise is present on a cold engine the same as a warm one. Anyway, I'm thinking of changing the plugs. If none of this works I guess I'll have to pull off the valve cover and look for anything visibly wrong with the valve train. Anybody else have any other suggestions? Thanks

 

[Froggmann]

Is your truck flex fuel?

 

[TomB1269]

The brake booster line is refernced on the can as that is the most likely and most accessable in all vehicles. I guarantee that using the vacuum port just behind the throttle boddy will do a better job. As the pressure is high (smaller port) and it will suck the fluid in and atomize better. I would venture a guess that your not getting all cylinders the same so the ping returns quicker.

 

[vpetersen]

99 3.0 flex fuel 5 speed 4wd. 132k miles.

 

[stmitch]

If you can find some e-85 around your area, I'd do what froggman suggested and run a couple of tanks of that. It will do a much better job of cleaning out your engine than seafoam or almost any other product. If you've never done it before though, be sure to start with a small amount, and then gradually increase the amount of e-85 you put in over a few fill ups. If you do too much e-85 at once in a vehicle that's not used to running it, the e-85 can clean the fuel system to quickly and can result in clogs from large clumps of goo that have become dislodged.

 

[Froggmann]

X2 E-85 puts seafoam and any injector cleaner on the market to shame.

 

[vpetersen]

I'll try the e-85 and get back to you in a week or so. Thanks for the input.