Engine Knock

[junior2ee]

I just noticed an annoying knock in my engine. The dealer said I probably put in some bad fuel and to go through 3 tanks before they would check out the problem. I've gone through 2 tanks and added Redline Complete Fuel Cleaner both times to the tank and still noticed the noise. This occurs most in the mornings, and around 2500rpm-3500rpm going on a slight slope. Are there any suggestions out there, and if anyone has any tips, please advise. Does anyone know if this is part of the coverage under Nissans warranty package?

[phathawaiian]

Ok brutha man..here's the scoop.

IF you own a 2004 maxima and there is a "knock"..FIrst take a deep breath, then, well, get to your dealership. I JUST, and I MEAN JUST got my car back today. I put it in the shop on March 31st 04. Today is the 10th of May. I had 32000 miles on my 04 and it developed this "knock". To make the long story short, my entire engine was replaced. Long block, cylinders, the whole nine. IT took so long because gaskets are still overseas along with the new cylinders (and there is a waiting line). My technician up at Nissan was sent to a training course on what to do when this happens and Nissan explained what the deal is. Basically there is this "butterfly valve" over your intake, that has a brass fitting. Well in original manufactering they didn't make this Brass bolt "locking" so over time is has a tendancy to shake loose and land in a cylinder, thus blowing that piston out. You'd think this would make a louder noise than just a "knock" but it doesn't. The car is driveable (trust me I drove mine almost 5K+ waiting for parts) Luckily my dealer fought for me to have a Murano rental car while mine was on his lift for a month waiting. Here's what I did..I called Nissan North America...and got my warranty pushed out to 100k (thankfully they had no problem with that), and Nissan put the new engine in (kinda happy my milage went back to Zero), and all is good now. Nissan made a "locking" brass bolt for the butterfly valve an we are all good. This has supposedly only happend to 20 cars in North America (according to my tech) but the issue can happen in ANY of the same engines as ours (should you own a 2004) this includes Murano's and some Altimas (i think).

If you have any other questions feel free to ask..good luck, and be very patient.

[sillyprettI]

I recently had to bring my car to the dealer b/c while I was driving my car shut down on me and i was no able to start it back up. Junior2ee...I was wondering were did these things happen to you before you brought to the dealer...After I read your post I do remember hearing my engine knock, but I really had to pay attention to it.

'04 Max

[BSTEVENS]

Man!! I own a 2004 Maxima. I believe that I am experiencing the same thisng that you are, I am not 100% sure though. When the engine is warmed up, and I depress the gas pedal at around 35-40 mph, you can here the tapping sound. It sounds exactly like valve tap to me.

I havent had the luck that you have with the dealer though. they said that the car was put on the computer, and that they cannot find anything wrong with the car. I am actually very frustrated as a result, but do not want to give up on trying to have the problem erraticated. I seem to be stuck at this point

Bstevens

[phathawaiian]

i'm sorry man. I can only hope they cooperate with you. Here's what do do. Tell them that you want it hooked up to the power meter they have at their shop. it's a specialized tool that does more than the little computer diagnostic they do "on the fly". FYI you can get your computer checked at Autozone for free! So anyway, ask them to put the car on this power machine and there they will be able to tell if there is cylinder damage. It's what they did for mine. Another thing to do is to describe my issues in detail. Ask the service manager and or the Dealership owner to look into it for you. If all else fails call NIssan North America, they are more willing to help than you think!! Feel free to keep asking me questions i'll be more than happy to help out. Update on mine. I got my warranty bumped to 100k, but unfort. i have delveloped a lower seal leak which is leaking oil at a rapid rate. I've applied for lemon law after this last visit to the shop. Oh, real quick. The knock can be heard at any time especially around accelaration from 35-50 and even on the highway going up and down speeds. it almost sounds like a lifter (if it were an old car!! LOL) but it's not. I also noticed a little bit of performance drop (still experiencing it) and if you know your car you'll be able to tell. Again, good luck, let me know if i can help further.

Phat

[hovz]

called like 5 autozones they said they dont do it, they loan you the machine for a 170$ deposit. but i dont know how to do it.

[ekg2]

Engine knock may be caused by more than one thing, in my case it was the ignition coil. Replaced all 6 of them at the dealer's and it solved the problem. They told me to use different type of gas too but it didn't work, so I ended up paying around $500 for parts & labor.