Knocking - Low RPM Knock

thats actually good news. you get a nice loaner, you get a new motor and its all free ... got to love Infiniti (sometimes)! seems like the only inconvenience was it happen during your move. hope thats going well, I hopefully will be moving later this year also (good move).
 
Wow.
Big list. Good thing it wasnt outa pocket

Very True

thats actually good news. you get a nice loaner, you get a new motor and its all free ... got to love Infiniti (sometimes)! seems like the only inconvenience was it happen during your move. hope thats going well, I hopefully will be moving later this year also (good move).

Yup, the move is slowly but surely happening.. Where are you moving?

so... did it cure the knocking issue?

Cured and running smooth :tup:

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If anybody lives in the San Jose / San Francisco area, Beshoff Infiniti is the best. They even showed us pics of some modded cars they are working on...even an 09 FX35 they fixed up with Superleggera rims... Mod friendly, the Metro Infiniti of Northern California. :glasses:
 
Mostly dealers aren't that into giving warranty when you did something to the engine.....sometimes they even ty to blame the air intake system or such........
 
Not to jack Jeff's thread or anything, but I'm posting my experience since it sounded like he was experiencing the exact same issue I was, or vice versa.

To make a long story short, I brought it in for a knock and the tech said it was normal. I wanted to believe him, but couldnt imagine what I was hearing was normal, so I brought it back in again and had a tech ride with me. He heard it and said it was not normal. End result:

Cust states knocking noise from engine at low RPM. Found engine is knocking. Perform tear down of upper oil pan and valve covers. Found main crank journal bearings are scorched and to have excessive clearance. Pulled camshaft caps and found bearings to have a blueish color. Replace longblock assy.
After repairs test drove vehicle. Vehicle had no codes store in system.


Parts-
DOWEL - PULLEY - 11022-AD200
WASHER OUTLET - 11062-AL501
PILOT CONVERTOR - 12330-14L00
GASKET - ADAPTER - 14032-AM600
GASKET - MANIFOLD - 14035-8J101
GASKET - EXHAUST - 20692-1E810
SEAL - O RING - 21049-AE000
V6 OIL UP TO 6 QUART - OILV6
WASHER - DRAIN - 11026-01M02
OIL FILTER - 15208-65F0C
MATIC J AUTO TRANSMI - 999MP-MTJ00P
LONG LIFE ANTI-FREEZE - 999MP-AF000P
REFRIGERANT - 999MP-R134ALB1
GASKET - EXHAUST MAN - 14036-AG010
GASKET - WATER INLET - 13050-31U05
ENGINE - BARE - 10102-AC3MI

***NOTE*** VEHICLE'S MOTOR NEEDS TO BE BROKEN IN AS STATED IN OWNER'S MANUAL PAGE 5-45"

Picked her up yesterday from the dealer. It feels so nice to be back behind the wheel of the FX. Hopefully, 3rd time is a charm. This is the 2nd long block replacement (3rd motor). First one was at 45K miles due to a knock at idle. This one was at 65K miles. So even though its a brand new motor, i'm a little jealous and envious of those of you who have gotten 100K+ problem free miles. lucky bastards!

My wife didnt hear the knock at first, but I kept insisting it was there. A buddy of mine said what he heard was normal and his G35 makes same noise. LOL I told him he should go get his engine checked out. hahaha.
 
Engine Noise

You are scaring me with all this engine replacement talk, especially since my 2003 FX35 has the same low rpm noise and is well out of warranty. Using a mechanic's stethoscope, I can isolate the noise down to the valvetrain on the exhaust side. I'm going to pull it apart to take a look. Well, I might first talk to a friend who works for Nissan.
Dave
 
Sorry for bringing this back from the dead - but,

fxlr8 -

The knock you were experiencing, did you notice it when it was very light sounding?
I just picked up a used Fx35 today - and I'm going over it thoroughly. I noticed a slight knock from the passenger side wheel area - and I actually heard it from the drivers side wheel area.
My stethoscope heard the knock loudest coming from the easiest accessible passenger side valve cover bolt. I checked all other areas. It's inside.

Did the noise eventually get louder and louder?

I'm used to the 4.0 Toyota engines (newer ones) and they are much louder than this - and it's normal. (not kidding - we put 60K on one - and 20K on another - everyone does it)
 
Sorry for bringing this back from the dead - but,

fxlr8 -

The knock you were experiencing, did you notice it when it was very light sounding?
I just picked up a used Fx35 today - and I'm going over it thoroughly. I noticed a slight knock from the passenger side wheel area - and I actually heard it from the drivers side wheel area.
My stethoscope heard the knock loudest coming from the easiest accessible passenger side valve cover bolt. I checked all other areas. It's inside.

Did the noise eventually get louder and louder?

I'm used to the 4.0 Toyota engines (newer ones) and they are much louder than this - and it's normal. (not kidding - we put 60K on one - and 20K on another - everyone does it)

That would definitly be the gas dampener in your case. Ik had the same issues.
 
That would definitly be the gas dampener in your case. Ik had the same issues.

Really? I thought that I stethoscoped it - and I didn't hear anything. It was pretty late last night though - and it was dark out.
It is positioned on the passenger side firewall area right?
 
The knock you were experiencing, did you notice it when it was very light sounding?
I just picked up a used Fx35 today - and I'm going over it thoroughly. I noticed a slight knock from the passenger side wheel area - and I actually heard it from the drivers side wheel area.
My stethoscope heard the knock loudest coming from the easiest accessible passenger side valve cover bolt. I checked all other areas. It's inside.

Did the noise eventually get louder and louder?

Yes light sound that got got faster as you pressed on the gas pedal. I had it fixed quick so it really never had a chance to get worse. Try listening around the oil pan closer to the crankshaft area.
 
Really? I thought that I stethoscoped it - and I didn't hear anything. It was pretty late last night though - and it was dark out.
It is positioned on the passenger side firewall area right?

Check out my post on the first page of this topic. It contains a PDF file. Check this out to exclude the gas dampener to be sure.

Good luck...!!
 
Hello guys I have an 2007 M35X I low rpm engine knock like FXLR8 it only happends when the motor is hot enough to turn the fans on if I just let it harm up enough so the temp gauge is at normal range and idol no knock and it goes away after 2000 rpm could this be carbon?
 
Hello guys I have an 2007 M35X I low rpm engine knock like FXLR8 it only happends when the motor is hot enough to turn the fans on if I just let it harm up enough so the temp gauge is at normal range and idol no knock and it goes away after 2000 rpm could this be carbon?

Ah you came to visit this forum. I'm actually dropping off my M this morning. If they say it is carb build up, have them clean it and if it happens again, ask for the money back. That's is what I am going to do. By the way, this is zerg711.. =)
 
Ah you came to visit this forum. I'm actually dropping off my M this morning. If they say it is carb build up, have them clean it and if it happens again, ask for the money back. That's is what I am going to do. By the way, this is zerg711.. =)


Ok well let me know the deal on this my M is going in on Tueday maybe you will know something before I do so you think it's carbon or we need new short block like this guy
also how many miles u have
 
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Well, my M35 went to the dealer and I may have the same problem as fxlr8. The dealer said a potential internal engine problem. The service manager said they had this problem before and the engine was replaced. Well, I guess I am getting a new engine that is replacing an engine with 21k miles on it -_- Thank goodness for warranty

Update: Problem has been isolated to cylinder 1.
 
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Well, my M35 went to the dealer and I may have the same problem as fxlr8. The dealer said a potential internal engine problem. The service manager said they had this problem before and the engine was replaced. Well, I guess I am getting a new engine that is replacing an engine with 21k miles on it -_- Thank goodness for warranty

Update: Problem has been isolated to cylinder 1.

And what is the exact problem then...?? Can't that be solved on the exhisting engine.....for example wenn out of warranty.
 
I still don't understand the whole knocking thing that well. I just can't seem to hear it. I know KNFX had an issue with it and even tried to show me in person and I don't think I really noticed it then. I hear a lot of lifter tap though.
 
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