The vanishing lifter tick

[AlwaysExplr87]

My brothers XJ has always had a little knock when under load or shifting into 4th. I never thought too much of it, mostly because mine did the same thing its whole life. Well I was driving it the other day and it got a little worse. We noticed that if you turn the heat on it disappears. The heat has to be all the way hot or it still knocks. My 4.0 knowledge has slipped over the past few years of driving a yota and any help would be appreciated. Anybody got any ideas as to what the issue could be? I'm thinking a vaccum or ignition issue, but thats just a shot in the dark.

 

[alosix]

Are you talking lifter tick or rod knock here?

My TJ (140k or so miles) is pretty noisy on cold startup, once warm it quiets down. Its gotten worse with age but has always been like that.

Now, Every time I've broken a header it starts out sounding like a lifter tick that goes away once it warms up (exhaust pip expands enough to close the crack). Once it gets bad enough it wont go away though.

 

[BIGdaddy]

no clue, if comes and goes with the HVAC system...

pulleys/bearings/water pump vanes...heck, squirrels in the engine compartment?

 

[BIGdaddy]

Are you talking lifter tick or rod knock here?

My TJ (140k or so miles) is pretty noisy on cold startup, once warm it quiets down. Its gotten worse with age but has always been like that.

Now, Every time I've broken a header it starts out sounding like a lifter tick that goes away once it warms up (exhaust pip expands enough to close the crack). Once it gets bad enough it wont go away though.

thats my vote, too.

 

[nobodyspecial]

I vote squirrels in the engine compartment.

 

[AlwaysExplr87]

Im not positive but it sounds like a lifter tick to me. Just like my old XJ, it ticks at start up but goes away, but when you put the engine under load (going uphill) or it shifts into fourth it ticks for a few seconds. I told him its nothing to be super concerned with, I've never rode in a jeep with over 100k that didn't do it. I was just wondering if there was an easy fix and thought it was odd it when't away with the heat. I'm Pretty sure its not a cracked header, for one its not an original manifold but a header and I was just under there checking that out not too long ago and didn't notice anything. I say we solve all the problems by pulling the 4.0 and droping some yota in there...

I kid, I kid

 

[bat]

When it starts to do it take a piece of metal tubing and put it to your ear and rest the other end on the valve cover you will no if it is a lifter. Becareful beacause the motor is running

 

[mudbutt]

What year?? The later model XJ's make that noise all the time.... It's normal. It's a solenoid that is part of the evap system...

The component with the two plastic-ish vacuum lines and one electrical connector, hanging off a rubber grommet is the EVAP purge solenoid. They are known to click and clack. It is the part of the evaporative emissions system that distributes fuel vapors into the intake manifold when commanded by the PCM.

Look here for a pic of the offender:

http://naxja.org/forum/showthread.php?t=1023502&highlight=tick

 

[XJCamper]

mudbutt, Nice call. As I was reading this post I was getting ready to go look for the link on NAXJA. This is probably exactly what he is hearing. My 99 makes this ticking sound at times. Sometimes louder than others.