Noise While Cruising

[Stinkbug]

I need some help, I have what sounds like Valve Clatter (sp) when cruising between 75-85. It is intermittent and only with around 10in of vac @ 2100-2400 rpm. I changed the plugs 2weeks ago and it did not change anything. Plugs looked good except they were red, is this normal? Truck has 78k miles, 2000 model with 3Lb and chip. Could this noise be coming from something else besides valves? EGR sticking or something. I do not get this noise anywhere else not even under hard accel. Sounds like its coming from the passenger side.

[L8 APEX]

Red stain is usually from octane booster or gas additive. You won't hear valves in an overhead cam engine like ours. May be tip-in detonation due to the colder weather? Poeple describe noises in different ways it is a hard thing to convey.

[Stinkbug]

Its been doing it for 5wks even in the warmer weather. The first time I noticed it I thought it was bad gas so I topped it off and added octane boost. Thats only the 3rd time in its life that its had oc boost in it. The right side head was replaced @ 62K, 26K miles ago.

[L-Fever]

Is your intercooler pump working? Mine was unplugged and I had some detonation noises for sure!

[L8 APEX]

Pull the chip and try it. Diablos are notorious for detonating

[Stinkbug]

Its ok to run the pulley without the chip?

[PoorSvtman]

with a 3lb you will be fine.... I ran my 2lb for a few months with no chip...

Just if your noise gets louder or you start to detonate get out of it.... I and i believe the chip only effects when WOT

[L8 APEX]

The stock program is more conservative than most anything out there. The 90mm will run a touch lean but it should let you find out of your problem is in the tune. Reset your battery after each change so the computer relearns the changes.

[Stinkbug]

Problem has not gotten any better and in some cases I think its worse. Chip is out and computer reset. The clatter is between 72-80mph with slight accell @ 10in of vac. I had the cruise set on 83 mph this morning and did not hear anything. Tonight I will remove 90mm maf and pulley. Man I really need this thing to hold together(Baby due in 13 days). Terry have you ever heard one with a burnt valve? Noise seems to be coming from L side, the side the head was replaced 36k ago.

:(

[L8 APEX]

Nope, sorry to hear about the troubles. If all else fails drop it off and I'll look it over.

[Silver_2000]

Sounds like classic tip in Detonation ... BUT seems weird that it happens with no chip. But you might have really crappy gas...

[Stinkbug]

Sounds like classic tip in Detonation ... BUT seems weird that it happens with no chip. But you might have really crappy gas...
Its been going on for 7 wks and I replaced the plugs 5 wks ago.

[Stinkbug]

Nope, sorry to hear about the troubles. If all else fails drop it off and I'll look it over.
Terry are you working tomorrow? I am still having this problem. If so whats the address I havent been to the shop since the muffler was installed 3years ago.

[L8 APEX]

Just call me AFTER 10am addy is 803 S Main St. 75137

[Stinkbug]

Ok, new twist. Terry I was headed over to see you last friday so that you could take a look. I went by to give her a good was before you took a look. I washed the engine compartment as well. After the wash the noise goes away, no more clatter its gone! WTF! It appears that the gas mileage is down to 10mpg still checking that. Then I remembered that when I first noticed this clatter coming back from south Texas the gas mileage had gotten extremly better like 18.5 mpg. Does this tell anyone anything? I will update after a couple of days and a couple of tanks of gas.:confused:

[Stinkbug]

I need some help, I have what sounds like Valve Clatter (sp) when cruising between 75-85. It is intermittent and only with around 10in of vac @ 2100-2400 rpm. I changed the plugs 2weeks ago and it did not change anything. Plugs looked good except they were red, is this normal? Truck has 78k miles, 2000 model with 3Lb and chip. Could this noise be coming from something else besides valves? EGR sticking or something. I do not get this noise anywhere else not even under hard accel. Sounds like its coming from the passenger side.


Update: I changed fuel filter and problem went away.:hammer:

[BLACKSUNSHINE]

Update: I changed fuel filter and problem went away.:hammer:

Woo Hoo knana :banana: :nana2

[CCCSVT]

If your gas mileage got that good it sounds like it was running really lean. 10 mpg sounds alot closer to what you'd expect than 18. Dunno why washing the engine compartment would fix the problem but am guessing that a computer or sensor got a kick in the head and woke up with the wash.

CCCSVT