My truck knocks.

Is there a quick fix, or do I have to live with it?

 

If it just started it could be a symptom of something else. If it has always done it, you can prob. figure out why and fix it.

 

Well it's been doing it for a while now, but I had the truck running while parked next to another vehicle and you could hear it echoing off the other car.

 

Search the threads for piston slap and knocking. seems like I have seen quite a bit about this and don't remember if anyone figured a fix or not.

 

ive got a 98' also... but mine has the 4.2 engine...... i sometimes hear a knock also under slight acceleration or going uphill (slight load), but only when i run 87octance gas.... when i switch to a slightly higher grade (Sunoco's 89 is what i usually run) the knock goes away.....
Anyone know why or whats going on here then??

i would assume that would not be piston slap

thanks..

 

Hmm, thanks for the suggestion. I'll run it down over the week, and put in some 89 and see if it goes away.

 

Check the torque on all yer spark plugs. People, including myself, report hearing a knock like noise prior to blowing a plug. Sounded like a lifter.

 

well its been happening for a while now, like 2-3 months. Just I heard it really loud when I had my truck next to another vehicle, and it was echoing off it.

 

Is it a steady or random knock? If it is a random knock, maybe some Techron fuel system cleaner would help. I pay about $10 for the 20 gallon size for my truck.

 

It's very steady.

 

4.6? Windsor or Romero?

 

lgjoe,

A '98 you say? It must have some miles on it now.With limited info I'd guess carbon build up in your EGR, the elbow and the intake, Try some "Seafoam". If that doesn't work you'll have to open it up and remove it by hand.

Good Luck

 

here is some more information on my pinging problem... hopefully someone has some good advice for me..
98' ... 4.2L.. approx. 190K (yes high milage)... i run 89 octance to stop the pinging that occurs with regular 87 octance gas.... the pinging occurs when im driving up a hill or under slight acceleration ... and can be fairly pronounced
the plugs are all ok and torgued correctly as a previous message was posted
i had the engine diagnosed awhile ago when it was discovered i had a faulty plug wire and the mechanic suggested possibly i should get a Motovac performed to clean out the EGR. I'm not sure if this is just a way to make more money for them or not.... or if it could fix my pinging...... Is it worth the money?
The pinging is funny.... when i do run 87 in the tank once and awhile.... it starts up almost right away like it knew i just put the stuff in...... and conversely.... when i switch back to 89 again it almost goes away right away.... within a few miles from leaving the station... is there another sensor that could cause this???
Thanks for your help...... lots of great information comes from this site

 

My 99 f150 with a 5.4 has a very pronounced knock. More so warm than cold. I have had it to a couple ford dealers. The best they have come up with is that the 5.4 has a tendency to get a crack in a piston skirt, causing the knock. Their advice: run it.

 

My 98' 4.6 also developed a ping a couple months ago
When it was hot outside it would ping ALL the time idle, under load, WOT, you name it. Now thats its cooled down a bit(Florida) I dont hear it at WOT anymore but still at idle and under light load.