[thejess]

I have a 2001 Xterra se with the 3.3 v6. And there is what sounds like a lifter tick or valve. Are the valves on the 3.3 adjustable or hydraulic? Also this caused the see light to come on and comes up as knock sensor. Any ideas?

 

[Grease Monkey]

It has hydraulic lifters..
but the noise can be deceiving as the injectors can make quite a racket on their own.. does it tick at an idle? does the tick go away with some revs?
Knock sensor failure is a pretty common issue (not related to your ticking) and theres a lot of info already on this site about it.

 

[mkgearhead]

It could also be a cracked exhaust manifold.

 

[thejess]

Ticks at an idle. So if the knock sensor comes up on a diagnostic test, does it need to be changed? Also how can the ticking be resolved?

 

[TJTJ]

Ticks at an idle. So if the knock sensor comes up on a diagnostic test, does it need to be changed? Also how can the ticking be resolved?

The sensor just senses knock. If its knocking, changing the sensor fixes nothing.

>

If its a tick, also try to see if it goes faster/slower with RPM, AND, stuff a rag in the exhaust (Unless you have asbestos hands, etc...) to block the exhaust, and, see if the ticking gets LOUDER when you block the exhaust.

You might need a buddy to do the gas pedal while you stuff the exhaust, or visa versa.

If you don't have a buddy, the ticking is then a minor problem, and you should concentrate on making friends first.

>

 

[ryan42]

TJ... :-D

The exhaust manifolds on these trucks do crack like crazy, and can sound very much like a lifter tick. In addition on the driver's side of the engine bay there is an evaporative control solenoid for the emissions system that sometimes runs on a duty cycle and makes quite a bit of racket, but it doesn't follow engine RPM. If you put you hand on the solenoid that has the two hoses going to it... one with a green cap... you an feel it and see if it lines up with what you're hearing.