Vibration?
Thread Starter
Joined: Dec 2004
Posts: 1,458
Likes: 6
From: Olivehurst, CA
Vibration? Ok, working through some post start up bugs. I have a vibration between 1700-1800 engine RPM. It happens in park, nuetral or while driving. Accelerating, Decelerating or holding steady RPM. It seems to be engine specific, not drivetrain. I did have some codes, O2 sensors until they were hooked up, then P0300 Intermittant misfire. I change plugs and cleaned my MAF and after a 5 mile drive I am still code free. Any suggestions of things to check? I have thought of double checking my converter bolts and will do that tomorrow.
Appreciate any ideas you might have.
Pat
Appreciate any ideas you might have.
Pat
On The Tree
Joined: Mar 2005
Posts: 125
Likes: 0
Idea.......... I'm sure you probably thought of this already, but in case you didn't........
Double check and tighten the trans mount, motor mounts, and driveshaft bolts. Good luck on finding the culprit. Once agian, ur stude is "bitchin"!
Double check and tighten the trans mount, motor mounts, and driveshaft bolts. Good luck on finding the culprit. Once agian, ur stude is "bitchin"!
TECH Resident
Joined: Oct 2004
Posts: 800
Likes: 1
From: Simi VAlley,CA
Stock LS engines seemed to be plagued with a little resonnant "buzz" at a small rpm band under 2000 rpm. We have been fielding complaints at the dealer level since the introduction of this engine in 1997. Currently there are several factory bulletins about isolating exhaust components and mount positioning/clearance mostly in trucks and SUVs. I think my conversion has escaped most of this as a result of my Corvette oil filled "bisquit" motor mounts. I still can feel a little buzz at about 1600-1700 rpm if I really look for it. One of the reasons I did a full-on race engine balance job was to try for the smoothest rotating assembly I could get, and it is very smooth. Making sure that none of the mounts are "loaded" and that no tension exists in fuel lines, steering lines etc. is also a good idea as they can transmit normal engine vibrations. One of my GM field engineer friends says this buzz has something to do with the firing order (?).
Thread Starter
Joined: Dec 2004
Posts: 1,458
Likes: 6
From: Olivehurst, CA
Thanks Oscar, that at least gives me an indication that it's not just mine. I thought the new firing order was supposed to smooth things out 
The torque converter bolts checked out plenty tight, so maybe it is just the nature of the beast? I think I have solved my misfire problem, or at least identified it. My modified headers are creating some challenges for the #3 spark plug wire. Even with ceramic coated headers and a heat resistant sleeve it managed to get fried. I am going to get a 90 degree boot for it and see if I can re-route it.
Pat
The torque converter bolts checked out plenty tight, so maybe it is just the nature of the beast? I think I have solved my misfire problem, or at least identified it. My modified headers are creating some challenges for the #3 spark plug wire. Even with ceramic coated headers and a heat resistant sleeve it managed to get fried. I am going to get a 90 degree boot for it and see if I can re-route it.
Pat
