Strange rattle on accelration/cruising.

[t0x1k]

I can't recreated it any other way besides driving, it doesn't do it at idle, revving, or creeping. It sounds like a heat shield is loose but its not(if it is, I can't find it) and it's very consistent with the rpms. It seems to only be during the lower RPM range 2400 and lower, very noticeable under acceleration.
I wish I could describe it better, but to me it sounds like a valve rattling or a bearing going bad, but it's fine at higher rpms, nice and smooth.

 

[Sasquatch_Ryda]

Sounds like detonation, also known as pinging happening.

You can try to run some seafoam or any other type of cumbustion chamber cleaner through it to clean the carbon out of it. See if that helps.

 

[trxusrngr]

My 1993 3.0 5spd is doing exact same thing...but it also happens while revving up! I just figured it was an exhaust sheild somewhere. I havent had time to crawl under it and look!

 

[Duane867]

Timing chain ?

 

[t0x1k]

Well, I installed a temp guage and it's running just shy of 210 degrees, and sea foamed it. It hasn't done it, but we will see. It smoked like a train afterwards.

 

[trxusrngr]

did you put the sea-foam in ur gas tank? or did you run it through the crankcase?

 

[trxusrngr]

any luck, did the sea foam shut it up?

 

[t0x1k]

I ran it through the vacuum. Seemed to work. The truck is running at 210 degrees so I might throw in the 180 degree thermostat.

 

[Big Jim M]

That is NORMAL!

I ran it through the vacuum. Seemed to work. The truck is running at 210 degrees so I might throw in the 180 degree thermostat.

210* is where it is SUPPOSED to run! That's the reason the gauges don't show the real temperature! Because the engine components are smarter than the operators are. If your engine wanted to run at 180* that would be the thermostat that came in the thing.
Just leave it alone and the engine will be happy!
Big JIm

 

[Ranger Kip]

age.... it happens with trucks too, just ask mine, its 26 years old and looks worse then a 80 year old drunk

 

[trxusrngr]

what do you mean you ran it through the vacuum? How do you do it?

 

[pillen140]

what do you mean you ran it through the vacuum? How do you do it?

brake booster vac hose.... let it suck it in slowly while running, but not too much or it will stall.


and if it isnt detonation, there is an exhaust shield attached to the bed above the muffler that rotts out a lot. could be lots of things.

 

[t0x1k]

I was def coming from the engine bay.
There must have been a lot of carbon cause after doing sea foam I made a post about sea foam and how it diesels and turned my engine over backwards.

 

[trxusrngr]

so just pull that fat hose off of the booster on the firewall, and let it suck out the bottle?

 

[Spitfire1975]

so just pull that fat hose off of the booster on the firewall, and let it suck out the bottle?

You slowly let it suck out about a third of the bottle and then turn the engine off. Let it sit for about 10 minutes and then restart it.

Be prepared to smoke out your neighbors, and not in a good way.