gooseabuse

Truck is a 2000 2.7L 4WD 5-speed. I'm hearing a ticking (actually sounds more like a knocking) when I come to a stop. When it does it (it's a random noise) it's a consistent rythm (does not change with RPM change). When the engine idles down it usually goes away. Sounds kind of like an old tractor. My 2001 with the same engine had the same kind of a rythmic knock, but wasn't as noticable as this one.

The engine seems to be running smooth and doesn't shudder at all.

Is this normal? If not, what could be causing it?

Skrillah

Good question, I was going to start a similar thread.

Mine isn't like yours though, it knocks at odd times. It will run and sound fine for a minute then all of the sudden I"ll hear a knock for 5 seconds then its fine again for a min, etc...

How many miles on yours? From what I understand, these engines need a valve job every so often although I'm not sure. Its possible if yours is making it all the time that its a leaking/bad exhaust manifold. These are known to fail on the 2.7s. Take off the heat shield on the passenger side of the engine and look around, you may very well find a crack.

I have already replaced my manifold once but I'm beginning to think mine is acting up again. The knock that my engine has is on the bottom side of the engine somewhere so I don't know. My valves/chains sound good when I do the screwdriver to the block test, so the manifold is about my only guess.

Hopefully someone will chime in with a better idea.

Skrillah

Anyone have any other ideas for the guy....? and me? lol

gooseabuse

I've paid a little more attention to mine and it only makes the knocking/ticking sound when I slow down from a speed of 30 miles per hour or greater. When I come to a stop (or slow down to at least around 5 miles per hour) it knocks/ticks (not too loud but I can hear it). If I remain stopped, it's like the engine idles down and it goes completely away.

I'm not familiar with knock sensors, but could it be that my knock sensor isn't compensating for the drop in RPMs? <- Or is that totally not even what the knock sensor does? No codes are showing.

g_mau18

From what Ive heard from many people and riding in other toyota's it seems every one of em including mine knock to some degree, When's the last time you had your valves lashed???

zlathim

That is totally not even what the knock sensor does. The knock sensor provides a signal to the ECU when it detects a knock/pinging. The ECU in return retards the timing. The knock sensor doesn't do anything except tell the ECU that your engine is making noise. You say your truck runs fine, so I am assuming that your knock sensor is not giving a signal to the ECU to retard the timing.

Your problem has me stumped. I am really having a hard time trying to figure out what could be causing an intermitent knock that does not relate to engine rpms in frequency. Unless you are calling an exhaust tick a knock.

Well, we are supposed to try to help, so I grabbed this outa my ass...

The sound happens on decelleration, right? Maybe your vehicle is backfiring ever so slightly on decel and you are hearing it leak out of the cracked exhaust manifold. No, really. I have no idea.

Do remove the heat shield from the manifold. The manifold is likely cracked. The easy way to diagnose would be to clean up and then seal the crack with J-B weld. Make sure you let it cure overnight. It won't be a permanent fix for the manifold, but if the noise goes away after plugging the crack, you know you found it.

Skrillah

Goose,

Again, i'd double check your manifold. That is probably the culprit. How many miles on the truck?

gooseabuse

I've got a mechanic looking at this and he says it's the power steering pump which makes sense.

But I've also got a chirping sound that occurs when I'm driving and either release the gas pedal or very slightly depress the gas pedal (it goes away when the gas pedal is fully depressed). The mechanic says this chirp is also related to the power steering pump.

Does that sound right? I've having him replace the pump because it does need replaced but could it be involved in an annoying chirping sound when the throttle is slightly depressed. I'm not saying I disagree, I'm saying my mechanical knowledge is limited .