Ticking sound

[mangolf]

Hi,
I have a new 2007 Grand Cherokee and upon acceleration it makes a ticking noise that sounds exactly like a valve lifter. Dealer says it's normal and is probably the catalytic converter material. It driving me nuts and would like to eliminate it.

This ticking is most noticeable with a mild-warm engine AND under light acceleration above 1000rpm. At idle it is hardly noticeable and revving up the engine in neutral without load does not produce this ticking sound. COASTING THERE IS NO TICKING sound, but at the slightest acceleration the ticking is there. To be clear this ticking is more related to a combination of engine load and rpm and is absolutely not related to speed. It is not loud but loud enough to hear it with the windows down and driving with or without lowfan-A/C.

It is very difficult to pinpoint where it is coming form. It is definitely not coming from any accessory belt driven devices. So far I could only find that it is SURE coming from the driver side as during idle it is noticeable in the driver side wheel well and is a little noticeable in the passenger side wheel well.

 

[Bounty__Hunter]

Sounds like an exhaust leak, and definately is not the catalyst in the converter. You can often narrow it down by placing your ear to the end of a long prybar or wooden dowel and (safely) placing the opposite end on different areas of the running engine.

I'd try a different 5-star dealer as well.

 

[ndnatty]

What engine do you have? I have a 2005 grand cherokee with the hemi and it had a tick when I first got it. It no longer does it, at least I don't notice it or haven't noticed it lately. I'll be more observant on my way home from work today an let you know if I hear it. I am thinking it fade with break in.

 

[redrooster]

You can verify that it is not a belt driven accessory by taking the belt off and running the engine. If you do this, do it when the engine is cool and run it for only a few minutes as the cooling system will not be operational without the belt.
I'm with Bounty though, it sounds like an exhaust leak either from the manifold to the engine or the manifold to the tailpipe (collector).
Keeping these things in mind, I would take it to another dealer. If this is normal then they should know what is making the noise and be able to show you where it is. Then you can determine if it is normal or not.

 

[idrthrbfishing]

I would look into the fuel injectors, they can tap/click under some conditions, this will normally go away as the injectors are worn under normal use. When I worked on hondas this was one of the most common complaints we had. Try switching fuel brands and a few cans on cleaner. This may free them up, they probably will not cause you any issues. A leaking exhaust is also a common cause of ticking, but I would look into the injectors. As for the dealer telling you its normal- I agree try another dealer. there is no excuse for them not looking into it and finding the noisy culprit. its there job, its under warrenty.
good luck.

 

[TwistedCU]

My '06 Unlimited had the same problem, the dealer replaced the lifters (they called them tappets) but it did not fix the problem. I sold the Jeep because of disgust with that and another unsolved issue.

 

[Sparky-Watts]

Besides the aforementioned suggestions, I'd also look for a crocodile with an alarm clock inside. Heard somewhere that there was one that gave a guy fits, but don't remember where.....

 

[Saurian]

I agree with exhaust leak, and noisy injectors, though I don't know if that's a problem with your engine, I know that the 4.0 has notoriously noisy injectors...

I nearly had a heart attack when my Jeep started a horrible knocking noise, very noticeable at idle, when accelerating, when revving with no load, it was bad, and I was freaking... Turns out that it's a cracked exhaust, again... Can't wait to get that fixed, because it sounds like my engine is on it's last legs the way it is right now. Good luck in your repairs, hope it's something as simple as the above-mentioned problems.

 

[mangolf]

Almost forgot, it's a 4.7L V8. Ticking is still there. Manytimes at idle sitting in a drive thru I can here it tick too. Another dealer said it is a moisture drain hole in the exhaust.....