Is this engine knock??

Nissan 300ZX technical discussion forum: Maintenance, performance, installations, modifications, how-to's and troubleshooting.
romeoridgee
Posts: 34
Joined: Tue Mar 18, 2014 12:39 pm
Car: 1993 Nissan 300zx 2+2 NA

Post

This was happening after my car sat for bout 2 hours after I was messing around with some mustangs. Note that my oil pan has a dent somehow in it, my oil was changed about 3500 miles ago and I already bought the oil and filter to change it tomoro morning.
:ohno:
youtube.com/watch?v=tcSoYDY8334


User avatar
veery
Posts: 158
Joined: Wed Oct 15, 2014 7:48 am
Car: 06 M35x Umbria Grey
Location: Danby NY

Post

Sounds like it's an exhaust system knock. An engine knock would be more regular time-wise.

ThisIsSparTTa
Posts: 738
Joined: Wed Sep 26, 2012 6:02 pm
Car: 91 300ZX TT 2+0

Post

Sounds like possible rod knock to me. Need to rev it to know more. Post a new video of revving it.

Here's what mine sounded like that turned out to be rod knock:
https://www.youtube.com/watch?v=kT8gmlimxJg
https://www.youtube.com/watch?v=mfw2CW7vqIg

romeoridgee
Posts: 34
Joined: Tue Mar 18, 2014 12:39 pm
Car: 1993 Nissan 300zx 2+2 NA

Post

I showed some guys who work on cars the same video and they say my engine is F****D. They confirm that it is rod knock and that i need another motor, if not to replace the crankshaft with a new piston and such. However I looked at the 2 videos above this post and did notice that the first one is in sync, mine is all over the place which make me unsure if it is even rod knock.. I dont want to post another video of the knocking because I dont want to chance to blow it up, so I can take it out and rebuild the lower end of it. Yes it does get louder and more frequent taps/knocks as I increase RPM.

My last oil change was about 3500 miles ago, after that ive been pulling hard on her since then because she is so fun to drive! Bernie replaced my motor in Feb and thought everything was in tip top shape, and never thought to check oil, (I didnt think the motor would burn oil as much as it did). I did an oil change yesturday morning and only 1 1/2 to 2 quarts of oil came out.. :wtf2: On top of that I have a dent on my oil pan which causes low oil pressure. I know exactly which bump it was and I went so slow over it, my stock struts are some s*** but still hit something down there. So Im guessing my engine was starved of oil. I plan on just getting another motor and swapping it out with another one with the help of other Z enthusiasts. I know all of you will say go tt, but I dont have the money to do that yet, and I know its a lot more than just putting in a tt motor.

romeoridgee
Posts: 34
Joined: Tue Mar 18, 2014 12:39 pm
Car: 1993 Nissan 300zx 2+2 NA

Post

ThisIsSparTTa wrote:Sounds like possible rod knock to me. Need to rev it to know more. Post a new video of revving it.

Here's what mine sounded like that turned out to be rod knock:
https://www.youtube.com/watch?v=kT8gmlimxJg
https://www.youtube.com/watch?v=mfw2CW7vqIg


Umm What the actual F... I just dont get it...

https://www.youtube.com/watch?v=vqw7ukS9rPw

It knocks when i rev it, but when rpms go down, its silent... and its not that loud when at idle.. Im think its something loose in the top end... and it sounds like the top end because I went under the car and it wasnt as loud as the top.

ThisIsSparTTa
Posts: 738
Joined: Wed Sep 26, 2012 6:02 pm
Car: 91 300ZX TT 2+0

Post

Checked your timing belt by counting teeth?


Return to “300ZX (Z32) Technical”