Well... I've been hearing this noise for a long time now... Actually I have heard it ever since I dropped in my engine.

The noise sounds like something rattling around like if you had a piece of lead inside a metal ball and shook it.

The noise only occurs when the engine is under a lot of stress
Going up a hill in a low gear
OR
Jamming hard down on the throttle

It almost sounds like a loose/gummed up lifter or tappet?

The only solution or reasonable cause for the problem that I have so far heard of is that my timing is slightly advanced and it is causing for the lifters to go a little crazy now and again.

I do not know where my timing is currently set.

Any ideas? What should I check? I would try to listen to the noise from the engine bay but I never hear it at idle

Note: IT IS NOT A ROD NOCK>> i heard that on my last engine

 

what engine is it?

 

the trucks a 1990 f150 4x4 with a 5.0L V8

 

If it is only under hard acceleration or a heavy load, I am going to guess that it is spark knock. This is a result of the timing being too far advanced. You should adjust the distributor to retard the timing a few degrees. Do not let it continue to knock - it will cause engine damage the longer it goes on.

 

I guess the first thing is to check my timing..

I will check it and report back. But that might not be until tomarrow.

What kind of engine damage?

 

Usually just accelerated bearing wear, but in extreme cases, holes in pistons, etc. It just puts unnecessary stress on the pistons, rods and crank. The knocking is the mixture auto-igniting before the piston reaches TDC, opposing the motion of the piston and crankshaft.

 

If spark knock, then a number of fixes:

first and foremost, route the #8 plug wire out of the harness and along the intake, far far away from #7. Most people dont realize is that the truck 5.0 has the same firing order as a chevy and hence the same crossfire issues.

that said,

replace cap and rotor with the accel units. I found that pretty much every other brand out there has excessive rotor-tip to cap post clearance NEW. let alone used. That is a lot of wasted spark energy.

btw the clamshell heat shield that surrounds the stock converter likes to shed bolts and rattle.....go give it a rap.

 

Turboguy, do you use Mobile gas? I have found that I ping significantly more when I run the Mobile lower octane gas. 91 does goodjusts costs more.
Tim

 

I had the same problem woth my 5.0 1989 Bronco. There is a spark knock sensor buried back behind the intake manifold. It took me about 4 hours to change but cured the problem. I had to remove the upper plenm, coil and I did the valve cover gaskets as well since I was there. The sensor is mounted in the block between the tranny and the intake manifold. It is extremely difficult to see but you can kind of feel it. It is about a 1" socket style sensor. Set your timing after you change it. 10 BTC I believe. Best of luck.

 

https://www.ford-trucks.com/user_gal...=52797&width=0

That's a picture of the knock sensor location. Hopefully the link works. If not, it's in my gallery, the one about wiring diagrams.

 

I wish I had that picture when I changed mine. Nice work EPNCSU2006.

 

EPNCSU200, you did not have to go through all the trouble to pull your engine just to show us where knock sensor was.

that's dedication!

 

I picked up a timing light today and will check my timing ASAP.

I use 87 octane gas and I am afraid that might be the culprit... I do have intake headers exhaust so that may upp my need for octane from what I understand...

is there a way to test if its the knock sensor is the problem? I dont want to spend all of that time and money to fix something that isnt broken...

 

Oh, it was easy to pull that motor. Just a few clicks of the mouse and there it was .

I think the Haynes manual has something about testing the knock sensor. I think what it amounts to is hooking up a timing light and watching the timing marks as someone taps on the engine with a hammer.

 

when you added the headers did you put socks on the wires? you may have a burn thru.