# Altima 2.5S 2003 Engine knock/valve clatter when cold...



## doc4bax (Jan 16, 2009)

Hey guys, new to forum. I have a problem. When I start my Altima it sounds fine when cold and at idle. Rev it up over 1500 -2000rpm and I hear a little valve clatter. Under load I hear a lot more valve clatter until the motor reaches operating temp (or close to it). I have checked the oil and its fine. I have been using 5W-30. The engine has about 36K on it. This noise has always been there during cold starts but its wasn't that noticeable. Now that its been very cold out (I live in St. Louis) the noise is more noticeable. I had brought the car in to Nissan dealer and got the runaround. My Altima is also a 5spd stick if that makes a difference. I wonder if this possibly could be an oil filter problem. I have been using the Super-Tech oil filters from Wal-Mart. I know that's probably not the best idea. Could it be that the bypass valve in these filters isn't working correctly (not opening and bypassing the filter in cold weather)? Would dropping to a 5W-20 oil help or going synthetic help? Or is this a different problem all together? Thanks for your help.


----------



## RB24SRB24DETT (Jan 9, 2009)

i suggest using nissan oil filters. ask the if you but extra will they give you a discount, if you like it get 5 or more if not buy 2. i work at nissan and if you want i can get them for you at $5.25 each one. i dont mean to scare you but the altimas usually have that problem but its around the timing chain. however you can replace it but it tends to come back. we end up trying to replace the motor. but try the oil filter first.


----------



## doc4bax (Jan 16, 2009)

Thanks for your advice. So what is going on with the timing chain? Is this chain typically bathed in oil and the oil is taking time to reach the timing chain because its cold? Thus causing some rattle/knock noise until the oil warms up and reaches the chain? My car is off warranty now. Why would you need to replace the motor for the a timing chain issue? Is there a tensioner for this chain that perhaps is malfunctioning? If so, I would think that would be a persistent problem. On mine, once the motor warms up the noise dissipates.


----------



## RB24SRB24DETT (Jan 9, 2009)

if it disappears you may be ok. its usually a constant knock. and its the chain and guide fighting against each other. ive seen people replace the chain and fix it and others fail. i suggest have someone look at it and determine whether its the chain or the valves. you may luck out and be ok. DO NOT use lucas oil additives. it is made for american made cars and will hurt your car more than it will help.


----------



## doc4bax (Jan 16, 2009)

What the heck...this is a Nissan! I shouldn't be having this problem lol. Yeah the noise is only during start up and only when its cold out. It's not a constant noise. I'm going to go with a synthetic oil and a Nissan filter (or a Wick) and see if that helps. This lack of lubrication to the valve train worries me and that's exactly what it sounds like. 

On a side note. I make short trips in my car as I live close to work. If I go with a synthetic oil, should oil changes still be down every 3K/3 months? From what I hear, synthetic does not have to be changed as often but with these short trips its going to get just as dirty as dino oils.


----------



## RB24SRB24DETT (Jan 9, 2009)

at nissan we change it every 3,750 mi


----------



## doc4bax (Jan 16, 2009)

Changed oil to 5W-20 and put on a new wix filter and I still hear the noise (valve clatter engine cold) but not as bad. I think it's not as bad because of the warmer weather, not the oil/filter change.


----------



## doc4bax (Jan 16, 2009)

Still have not found a fix for this. Ok, I’ve read just about every post there is on this and have not got an answer that has solved the problem. My engine has valve clatter when it’s cold. The noise is only under engine load (driving) and does not dissipate until operating temperature is reached. I can rev it up at idle when cold and no noticeable valve clatter. Put it in gear and begin to accelerate and you can hear the clatter. Let off the gas and coast and no noise, give it a little gas and there again, clatter! I have heard it’s because of the oil filter, well I put a Nissan one on and put synthetic oil in and nothing changed. I have heard it’s the heat shields and have inspected them all and they are all good and tight. I have heard that this noise is” normal”. No way is this normal. The noise I hear sounds like a valve train starved for oil. It’s valve clatter without a doubt. Or possibly the cam spockets or chain rattling. I have not taken it to the dealer as of yet because I have read so many stories about people with the same problem and the dealer giving them the run around. No one has seemed to get this problem resolved and has spent a lot of money at the dealer for nothing. From what I have read, the only thing I can come up with is it’s probably the cam sprockets and the variable valve timing solenoid or something related to it. Has anyone with this problem had their variable valve timing solenoid replaced and if so, did it fix the problem? Or did you have the ECM reprogrammed and it took care of it? This question is for people experiencing the same thing I am. This is not a few second or few minute ordeal. This is a problem that occurs when it cold outside (40 degrees or lower, the colder it is out the louder the clatter) and it lasts until the temperature of the motor reaches normal. My car is a 2003 2.5L 5sp. Most of these TSB don’t even apply to me with regard to heat shields and reprogramming the ECM. I do believe the 2.5L engine valve train has changed since 2002.


----------



## rondhol (Nov 23, 2008)

I have excatly same problem. Colder temp = Louder tapping noise under load. It is gone after the engine is fullly warm. It could be piston slap or qr25de solid lifter noise that not effect drivability. :balls: Do you have oil consumption issue? My 2.5S burns 0.5 quarts every 1k miles with Super Tech full synt./PP. 5w-30. mobil 1 0w-40 may reduce the noise and oil consumption.


----------



## doc4bax (Jan 16, 2009)

rondhol said:


> I have excatly same problem. Colder temp = Louder tapping noise under load. It is gone after the engine is fullly warm. It could be piston slap or qr25de solid lifter noise that not effect drivability. :balls: Do you have oil consumption issue? My 2.5S burns 0.5 quarts every 1k miles with Super Tech full synt./PP. 5w-30. mobil 1 0w-40 may reduce the noise and oil consumption.


Piston slap?...no way. It's the damn intake sprocket slapping until the oil is warm and thin. I should remove the screens off the variable valve timing solenoid. I bet that is part of the problem. If you are burning oil I would yank the precat like NOW. It's probably discinigrating and being sucked in the exhaust and in the motor trashing your rings and cylinders. I made that fix, got a header before the precat fell apart. Nissan, what a pile of sheeeit. I won't ever buy another one.


----------



## rondhol (Nov 23, 2008)

Thanks FYI. I had new pre-cat and the oil consumption is high but still acceptable. No need refilling after 3k. Let me know if you have fixed that problem with removing screen, etc. My first guess is too wide/worn valve lifter, you can check the clearance.


----------



## doc4bax (Jan 16, 2009)

I was just talking to a guy who has an older 240. He says in cold weather his does the same thing. Not sure why Nissans are prone to this problem.


----------



## rondhol (Nov 23, 2008)

It is the sound of solid lifter, once get warm, it's quiet.M1 0w-40 and GC 0w-30 help a little bit.


----------

