So I got a few things done Monday. Got a new Radiator installed, a new belt (Alt,AC ect), Thermostat w/ housing and a 40 series Flowmaster with a magnaflow split tip. I thought everything was now going to be great except the next day I started hearing a little bit of valve chatter. I filled up (With premium,always) and now my valves are raising absolute hell. I put seafoam in the gas and it seemed to help a little, but now its back bad.

The chattering is at its worst in second gear. Also, I used to get a little bit of valve noise when the AC was on in 2nd, but now with no AC, its worse.

The place I got my gas is a Shell station but Im wondering if maybe they're running 87' octane in its place to get a quick buck. I honestly have no idea though, all I know is at the time my car should be running its best, its not. Any suggestions as to what might have happened?

 

Have you checked you oil level?

 

oil?

 

Yea whats oil?

 

I smell an engine rebuild...........anyone else? Even if it was 87, it will not sound like you describe. I've run 87 octane in mine for over 85k miles without a single issue or noise (knock on wood).

 

check ur oil... might not have enough oil pressure....

 

check oil, you gotta change it anyway from that seafoam.

 

wouldn't not enough oil which would result in low or no oil pressure bring up a dash light?

change your oil or have it changed and report back

 

Yeah, the oil is fine. I run 10/30 mobile synthetic with a Mobile filter.

I got the car at 30K, its at 115K now and it has always had a little bit of valve rattle with the AC running through second, and it has always been worse with reg octane gas.

Now, with the AC off its doing it. The weird part to me is that it doesnt do it under heavy power. At a gradual build-up is when it does it, which is weird to me because theres no stress on the motor.

The car is still just as poweful as the day I got it.

Is it possible the timing might need adjusting?

 

Changed it last week.

 

Yeah, I put it in the tank, not the motor this time.

 

my guess is it is timing chain related. I don't know the specific part that tends to give everybody trouble but it think it is the timing chain tensioner sprocket.

somebody ring in that has a little more experience than me with this issue

 

is the noise only while moving or can you hear it at idle? if you can hear it at idle you should use a long screwdriver and place it around the engine(safely) while listening to the handle to pin-point the noise, i dont see how it would be valve chatter if it was worst in 2nd , i had a bad bucket lifter that you could hear wenever the engine was running that was loudest from 1500-3000rpm.
any codes??

 

engine of couse.

 

Ok,awesome, hopefully somebody can shed a little more light on this and what I'll need to do.

 

timing chain possibly?

 

No codes. Running at idle, shes as quite as a sleeping newborn baby.

I grew up driving a F-150 which had a very emotional 351 Windsor on the top, I had a time with the octane because I'd get valve rattle with curtain quility grades of 87'. Hell, my wifes 98" Grand Charekkee, if she gets 87' octane at Walmarts Murphy Gas station twice in a row, her valves start pinging like crazy. Maybe we have ****ty gas here, I dont know.

Im most concerned now if this could be what Feldman pointed out, a timing chain issue or timing or something. Is there anyway I can find out without get my **** raped by a dealer?

 

I have what seems to be a similar "noise". I thought that it had to do with the fact that I installed a LTB Stage 1 a while back and it was pressing the heat shield, which would cause a faint chatter, but the wierd thing is that it doesnt occur when the engine is cold, only when its warm. I installed an oil catch can a long time ago, and regularly change my oil myself every 3K miles with conventional Castrol GT-X 5w30. However, more recently it makes this "chatter" when I am literally cruising, i.e., in my neighborhood going around 15-20 or in a parking lot, NOT under load. It makes my car sound like crap when it still runs like a champ. I have around 118k miles and have owned and babied it since 30K on the odo. Around 60K while replacing my plugs, I did notice oil in chamber (6) I believe, if standing at front of car, the chamber located at the far back right, closest to driver seat. I was still under warranty so I received new gaskets and coil pack. I am about to replace my plugs again in the near future and hope to not find oil in that same chamber again. Anyhow, thats the history of the only problems I have had with this car. I will keep up with this thread and I am very interested in hoping to figure out this problem.

 

you have to find where the noice is comming from, not just "from the engine".

 

pinpointing the noise would help us a lot

 

do you have audio clip of that sound???

 

Right! How do you propose that I do this?? I told you it sounds like valves, without having somebody drive the car and me climb into the engine bay, I really dont know how to get the information you need. Its Valves, what I need to know is why and or how to fix it, if anybody can help with that.

 

I dont, but if youve ever heard valves pinging, that pretty much what it sounds like to me.

 

Ironic. I noticed this morning, at 60 degrees driving down the road it wasnt making the noise. 2 hours later its 73 degrees and the motor is warm and I can hear a slight pinging. Havent run it this afternoon but I will later. I added another can of Seafoam, to see if that has any effect.

I did notice what looks like Oil at the back of the motor,on top, behind the 3.5Heat Shield, closest to the firewall. Is there a vacuum valve back there that would cause that?

 

You don't have a valve issue, you have engine knock or PING. Thats what your hearing, normally happens under a load, especially when it's hot and while you accellerate, is that when you hear it???
Being it didn't happen when it was cold also tells me it's ping or spark knock.

There are many issue that can cause engine ping. Bad MAF, timing issues, fuel issues, O2 sensors ect.

Being you cannot identify it, have it checked out by a qualified mechanic.

 

I had all the O2 sensors replaced 6K ago, fuel has always been 93 octane and Ive been using Seafoam as long as Ive had the car.

When I accellerate, it doesnt "ping", its when Im kinda easing along and its in 2nd when it pings.

 

I bet you have oil in one of the spark plugs.

Is that by any chance a 5.9 V8?

 

Where do you think the oil is coming from? It looks like blow-by from somewhere. The car doesnt use any oil or anything so it seems like whatever it is is minor? If thats possible.



I wish. No, its a 4.3 v6

 

These are from two different cars that I fixed within the past month:



To confirm without vqspidisense, stethescope on rear valve cover. The bucket shims that sit between the cam & valve like to get smoked on the rear bank exhaust. The first time to confirm I also pulled all injectors to make sure it wasn't an injector (pulled manifold off for cyl #3).

To fully confirm you need to pull the rear valve cover and follow the procedure for checking the valve clearance (The only spec on the hood sticker, I always thought it was so pointless, lol)

To remedy, unfortunatly nissan screwed the 3.5 guys over and made it so cam removal is required unlike on the 3.0's which I've seen with 300k plus without a lick of excessive valve clearance. Once you have the worn down shims out you simply need to read the size #'s stamped on them and order the appropriate shims.

What this means though is removal of the outer timing cover, and than the primary and secondary chain assembly's. It's a PITA job in the car, probably the most advanced one that doesn't nescessatate engine removal. Removal of the upper oil-pan is highly recommended, allthough out of the 6 times I've removed a vq outer cover in the car without dropping the pan I haven't had a single leak long or short term except for on the 6th time! BUT the guy demanded to pick the car up way early and might be trying to scam me/not have a leak as well, it's a ****ty/sketchy story. But expect to pay between $850-$1400 in labor alone.

If you need any more advice or help with this problem feel free to give me a call, I could probably ramble off every bolt that needs to be taken off and it's size, + tourqe specs for the important ones, lol, and I'm always willing to help .org members out with repair tips or advice. You'll also find some good info in the EM section of the fsm.

Kevin

 

I dont know. Ive heard about leaky valve covers causing problems. Wouldnt you know, just today I noticed strange noises at lower rpms when accelerating. I hope its some kind of heat shield and not valves.

 

My.....god.. Ok guys, well it looks like Im going to be taking my Max to trade it in today on another, maybe the new 15th Gen haha

Kevin, I appreciate your help. What could cause those bucket shims to fail. Is their location a high stress area or are their envirnmental issues to blame, or both? Im honestly a little apprehensive about taking it to a dealer mech right now before Im convinced this problem is out of my control(ie if its going to take more then changing the air filter). Again, my car has done this since 30K,(im at 115K currently) its just now, it got really loud.

Yesterday it was cooler outside and I didnt hear really any pinging. Let me ask you this, could this problem be as simple as a knock sensor?

Second question, is their a PVC Valve located on the motor anywhere?

I really appreciate your input, thank you!

 

Hmm, this the top rear of the motor where the oil ends up? The weird thing is I dont see oil anywhere else, just on the back. Thats why I wonder if theres maybe a PVC Valve back there that may need replacing/

 

If the bucket and shim was worn he'd hear a tap constantly at any speed, at any temperature, including idle.

That's not his case.

 

Search for "oil catch can" for pics of the PCV valve location. To add to my normal maintance I regularly change my PCV valve every 25-30K miles and I also used seafoam before replacing my manual tranny fluid with Amsoil every 30-35K miles.

 

the pcv is located ontop of the rear valve cover on the passenger side, if you had knock sensor issue you would have a code, but from what you are saying it sounds like you have knock issues, do us a favor, put the front of the car on jack stands so the tires are off the ground, put it in drive or in gear(dont floor it) and start accellerating to the point where you can hear it, and have someone record the noise.

also if you just had your belt serviced, the mechanic who worked on your car maybe have over tighten it, check to make sure you can turn the belt over an 1/8 or 1/4 of a turn, it sounds like the clutch on the compressor has gone bad, and the tensoin on the belt could be making your a/c clutch louder.

 

The link to the Oil Catch can repair isnt working, do you know of another? It sounds like I am about 115K overdue for replacing my pvc valve, judging from the oil spillage it needs to be done ASAP.


I have put off changing my tranny for so long Im really embarrassed
about that. Whats Amsoil? Is that a cleaner or a replacement fluid for the OEM tranny fluid? I havent had it done because honestly given my past experiences with the NIssan dealer, Im afraid they wont do a good job. Ive got a buddy that owns a shop that said he'd do it but again Im apprehensive because I really havent figured out what I need to correctly service my tranny without quelling the fear that Ive let it go to long without servicing and might screw it up if I service it now. What do you think?

 

Ok, yeah, get this, I ran Seafoam the other day and it seemed to do some good then starting pinging again. So, I put another can of Seafoam in it yesterday. I drove it 110miles yesterday and it didnt ping once?! Granted, it was cooler last night and yesterday morning but my regardless, it didnt ping. What do you think about that?

Also, I did get my AC Clutch replaced 7 months ago, actually everything except the compressor was replaced under warranty. I will check the belt despite that because as you say, it'll put stress on it, new or old.

 

I got my PVC Valve from Autozone this morning, it was $15 buck, seemed kinda steep being Ive seen them for 10 on the interweb. Anyway, I found the oem pvc valve and looks like it'll be easy to take out, install.

Also, had a little bit of pinging this morning, but this time it would start if I kinda got into the gas a little bit. If I just eased around I didnt hear anything, it was when I got on it a little is when I could hear it. The sound I can describe as "ting tingting ting", if that helps

 

See the first few words in post #5....

 

No way man, no way. This car is strong, uses zero oil, and with Seafoam the pinging is nearly non-existent.