Ok guys i have a 2012 jeep jk with the new pentastar 3.6 in it. It taps on start up after it sits for about a day its a very light tapping noise and doesnt last long at all maybe 2 secs or so and you cant hear it unless the door is open. Jeep has 650 miles on it I did the first oil change at 600 miles with 5w-30 mobil 1 EP but it still made the tapping even with the factory fill oil. And it does it with mobil 1 ep also. Anyone have any ideas of what this could be? Is it hurting anything?
2012 pentastar 3.6 tapping on cold startup
- Thread starter vinsonclarkjeep
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My guess is faulty ADBV in the filter. Many engines make tapping noises on cold startup, even in perfect condition. Engines make weird noises when cold. What filter did you use?
Went with a wix filter. The filter is mounted on top of the engine its a cartridge style filter. Never ran a engine with this style of filter before do they even have a ADBV?
Originally Posted By: Popinski
Whatever it is, I hope Chrysler fixes it for free.
Did the owner's manual say, "5w30"?
Yes owners manual specs 5w-30. And im sure they will if its something serious but i dont no much about DOHC engines
Whatever it is, I hope Chrysler fixes it for free.
Did the owner's manual say, "5w30"?
Yes owners manual specs 5w-30. And im sure they will if its something serious but i dont no much about DOHC engines
I would be taking it back to the dealer. Have them put an oil pressure gauge on it and do a cold start. Could be a leaking oil pump. If they say "They all do that" then ask to cold start one on the lot and see if it does it.
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Originally Posted By: Doog
I would be taking it back to the dealer. Have them put an oil pressure gauge on it and do a cold start. Could be a leaking oil pump. If they say "They all do that" then ask to cold start one on the lot and see if it does it.
Thats a good idea. I will wait till in the morning if it does it in the morning i will take it to dealer and have them check it out. The jeep has to sit for more than a day to do it though?
I would be taking it back to the dealer. Have them put an oil pressure gauge on it and do a cold start. Could be a leaking oil pump. If they say "They all do that" then ask to cold start one on the lot and see if it does it.
Thats a good idea. I will wait till in the morning if it does it in the morning i will take it to dealer and have them check it out. The jeep has to sit for more than a day to do it though?
Sounds like something going on with a anti-drainback valve. Bad oil filter?
i have an 07 with the 3.8, it does the same thing unless i use wix filters, i even tried p1 filters and still clacked on start up, i know it is a differnt engine but it may have the same filter location/position.
Agree that the dealer should listen to it and note in the "permanent record" that this issue was reported.
That said, almost all engines with hydraulic lifters or lash adjusters will occasionally tick on startup, regardless of how good the ADBV is. The reason is that no matter where the crankshaft stops turning, at least ONE valve will be held partially open the whole time the engine is turned off, and the spring pressure on that valve will cause its lash adjuster to bleed down and allow some clearance until the oil reaches it after after the next startup. That's generally harmless, but the LENGTH of time it takes can be indicative of a leaky ADBV.
That said, almost all engines with hydraulic lifters or lash adjusters will occasionally tick on startup, regardless of how good the ADBV is. The reason is that no matter where the crankshaft stops turning, at least ONE valve will be held partially open the whole time the engine is turned off, and the spring pressure on that valve will cause its lash adjuster to bleed down and allow some clearance until the oil reaches it after after the next startup. That's generally harmless, but the LENGTH of time it takes can be indicative of a leaky ADBV.
Originally Posted By: 440Magnum
Agree that the dealer should listen to it and note in the "permanent record" that this issue was reported.
That said, almost all engines with hydraulic lifters or lash adjusters will occasionally tick on startup, regardless of how good the ADBV is. The reason is that no matter where the crankshaft stops turning, at least ONE valve will be held partially open the whole time the engine is turned off, and the spring pressure on that valve will cause its lash adjuster to bleed down and allow some clearance until the oil reaches it after after the next startup. That's generally harmless, but the LENGTH of time it takes can be indicative of a leaky ADBV.
+1
also depends on how fast the lifter(s) can get pumped back up. dirty/partially clogged lifters will make noise longer while refilling with oil. the longer they are let to drain, the longer it takes for them to refill.
tho i would be really surprised with that being on a new vehicle. normally you see that on beaters. lol.
Agree that the dealer should listen to it and note in the "permanent record" that this issue was reported.
That said, almost all engines with hydraulic lifters or lash adjusters will occasionally tick on startup, regardless of how good the ADBV is. The reason is that no matter where the crankshaft stops turning, at least ONE valve will be held partially open the whole time the engine is turned off, and the spring pressure on that valve will cause its lash adjuster to bleed down and allow some clearance until the oil reaches it after after the next startup. That's generally harmless, but the LENGTH of time it takes can be indicative of a leaky ADBV.
+1
also depends on how fast the lifter(s) can get pumped back up. dirty/partially clogged lifters will make noise longer while refilling with oil. the longer they are let to drain, the longer it takes for them to refill.
tho i would be really surprised with that being on a new vehicle. normally you see that on beaters. lol.
Originally Posted By: silverrat
Pentastar engines use the cartridge type filter and is located on the top of the engine.
Yes thats it. These filters dont even have a ADBV do they?
Pentastar engines use the cartridge type filter and is located on the top of the engine.
Yes thats it. These filters dont even have a ADBV do they?
my 2008 cherokee tapped a LOT when it was new. it was enough that I'd pour 1/2 qt of 10-30 in with the rest of the 5-20 when I did an oil change, which would settle it down. Now, +40,000 later it has quieted down to nothing, running good 'ole 5-20. It's taken a long time for whatever that was to "wear in." the fuel injectors are also very loud, and it's hard to discern the difference between injector and valves.
If it's only for 2 seconds, and you can't hear it inside, I wouldn't worry about it. system is just building up fluid pressure.
and if it's that faint, no dealer in their right mind is going to pay attention.
If it's only for 2 seconds, and you can't hear it inside, I wouldn't worry about it. system is just building up fluid pressure.
and if it's that faint, no dealer in their right mind is going to pay attention.
Originally Posted By: vinsonclarkjeep
Originally Posted By: silverrat
Pentastar engines use the cartridge type filter and is located on the top of the engine.
Yes thats it. These filters dont even have a ADBV do they?
The ADBV is built into the block.
Originally Posted By: silverrat
Pentastar engines use the cartridge type filter and is located on the top of the engine.
Yes thats it. These filters dont even have a ADBV do they?
The ADBV is built into the block.
Everyone will say I'm crazy, but I've always heard more engine/tranny noise with synthetic fluids. And I'd go back with the OEM oil filter.
There was a lengthy thread on JeepForum about this noise. It's just another Jeep thing.
Originally Posted By: meep
Now, +40,000 later it has quieted down to nothing, running good 'ole 5-20. It's taken a long time for whatever that was to "wear in."
+1 Lifters and lash adjusters rely on metal-to-metal seal to hold the oil in when shut down overnight. As they wear in, the seal gets better.
Now, +40,000 later it has quieted down to nothing, running good 'ole 5-20. It's taken a long time for whatever that was to "wear in."
+1 Lifters and lash adjusters rely on metal-to-metal seal to hold the oil in when shut down overnight. As they wear in, the seal gets better.
If someone would have just loaded that thing up HARD when new it would have been quiet as a mouse.
Slow break in is a silent killer.
Slow break in is a silent killer.
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