Dodge Dakota Engine Noise

ted690

Need help! I recently purchased a 2006 Doge Dakota with a 3.7 litre V- 6 engine with 17,000 miles. There is a ticking sound coming from under the plastic manifold on top of the engine at idle. Does anyone know if this is normal or some kind of valve tap? Also, the engine seems to wonder in RPM's like a variable idle speed...not much, but enough to hear and see it on the tach as the needle just hovers a little above and below 700 RPM. Any input would be appreciated.

dustyk

I'm not aware of any common problems associated with engine noise on a 3.7. It is difficult to appraise your issue without hearing the noise for myself, but I've heard my share of these 3.7s run and they've all been quite quiet and completely absent and ticking noises. It is pretty much impractical to try to troubleshoot noises over the internet. Noises can fool you even if you're standing over the engine while its running.

However, that doesn't mean there aren't exceptions. Based on your report I'm momentarily at a loss to make a guess, though, because the lifters and rockers are in the cylinder head and there is no center camshaft below the intake manifold. How is the oil pressure? Are you using the correct oil (5W30) and the correct oil filter? Does the noise vary with engine temperature or some other condition?

I'd try to get a hold of a stethoscope and search for the noise.

Regards,
Dusty

ted690

Thanks for the input Dustyk. As far as the oil goes, I assume the dealer put in the right oil. It has a mopar oil filter. And no, the ticking noise is only present at idle..nothing varies. I was told by someone else that it could the the fuel injectors opening and closing. He has an F-150 and said his his twice as loud.

dustyk

Well, I'd probably believe a noisy injector before I'd suspect any valve train noise on a 3.7 or 4.7, unless it's very high mileage (200K plus). My 4.7 does make a very, very, very small ticking noise when first started, but goes away after about one-two minutes of running. I've never tried to determine what was causing this because it is so minor. On some days it can't be heard at all. This, in fact, could be injector noise, especially since I have 117K on my Dak.

Best regards,
Dusty

ted690

Thanks Dusty,
I'm going to bring the truck back to the dealer in the next couple days so they can hear it.
They just replaced the exhaust from the Y pipe back because they said someone had improperly installed an after market exhaust. It looks to me they installed a new pipe back from the Y to the rear muffler and a new tail pipe. What I found to be suspicious is they left out the front muffler. At least I think there is supposed to be a front muffler. This is one of those Dodge certified used trucks. What I don't understand is why this was not picked up in the precertification inspection. I'll let you know what they say.
Thanks, Ted
Thanks,
Ted

dustyk

Hmmm, the 2001-2004 Dakotas only had one muffler. What you might be referring to is a resonator, but again, those were not used from '01-04. I don't know if the '05 and up got a resonator. I do know the exhaust system is a little different on newer models.

Best regards,
Dusty

bugz2008

The 4.7's have hydraulic valve lashers to maintain a zero tolerence... takes a minute or two for them to pump up, that results in a light to sometimes medium tick when first started, even when warmed up... but it shouldnt last more than 30 seconds to a couple of minutes.

I have heard some that sound like diesals when first started after they had sat for a while...and it goes away after a minute or so.

But Im not sure the 3.7's have the valve lashers... I have never heard one tick.