# HELP!! Knocking noise coming from engine



## gsxr062309 (Sep 29, 2012)

06 Altima 3.5 SE 98k
Here's the deal, I've noticed a light knocking noise coming from my engine that I can only hear in the cabin mainly because it only does it when the car is in gear. When I first start the car on occasion I get a rattling noise for a split second. Once I put it in gear, almost all of the time, I hear a knocking noise. It's not that bad but it's bad enough to drive me crazy. It has 98k on it and gets regular oil changes! I don't want to take it to the dealership and pay only for them to tell me they can't hear it or it's "normal". Anybody else having or have had the same issue?! Please help!!:newbie:


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## rogoman (Dec 16, 2004)

The oil pressure may be very low. You can check the pressure very easily by installing a temporary mechanical oil pressure gauge. You would remove the oil sensor which is located next to the oil filter and install the mechanical oil pressure gauge in it's place; you may need to get an 1/8 BSPT to 1/8 NPT adapter to hook up the gauge.

With the engine fully warmed up, the pressure should be as follows:
idle - at least 14 psi
2000 RPM - at least 43 psi

Also what brand of oil filter do you use? Avoid using a Fram filter. Go with a genuine Nissan or purolator filter.


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## smj999smj (Jan 1, 2006)

You may want to look for a copy of Nissan service bulletin NTB07-010a. It refers to a "clicking, thumping, ticking, flutter, buzz or knocking noise" heard in the passenger compartment but eminating from the engine compartment. Applies to 06-06 Altimas w/ 3.5L-V6. The stated cause is due to both fuel dampers. I can't say it's definitely your problem, but worth looking into.


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## gsxr062309 (Sep 29, 2012)

*Problem located!!!!*

Thanks for the responses! I ended up just letting them look at it, and it's a good thing I did! Turns out it was the timing chain which was about completely shot and the fuel pump was pulsating. Luckily I am covered with my warranty and should have her back by the end of the week. I was going to try to self diagnose the problem, but not being great with mechanical work I figured I was best to take it in and I was right. I dodged a bullet that's for sure.  Thanks again!!!


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