Kentetsu

I seemed to have developed an engine vibration at high rpms that I don't believe was there before. It only seems to be there when I go over about 5k rpms. It's not real severe, but I don't want to ruin my motor. Its a really high pitched vibration which seems to correspond to engine rpms.

The engine still seems strong and everything, but I'm afraid to take her up to higher rpms until I figure out what's going on. I'm pretty sure that the engine is what's vibrating, doesn't make a difference if the clutch is in or not.

It almost feels like the exhaust is rubbing on the frame, and I haven't been able to check this yet, but it wasn't there before and the exhaust was installed about 8 months ago.

What could cause this vibration? Thanks...

pimpncuba

could be the driveshaft

Kentetsu

Thanks for the input, but no. The vibration is consistent with engine rpms and does not change with vehicle speed. I've experienced driveline vibration before and am confident that this is not related to the driveline. Thanks...

GLC13B

How long has that engine in the car ? There's a couple of different things that could be the cause of this vibration ! So, now if the engine was recently pulled or not is where i would start the process of elimination.

Kentetsu

Original engine, untouched with 190,000 miles on it. No oil loss or burning. Vibration is not severe, but I seem to recall that a rotary that I had before was very smooth all the way to the redline. Thanks.

Kentetsu

Found the problem. One of my exhaust hangers came loose allowing the exhaust to rest against the frame. Back to silkey smooth high revving once again!

pimpncuba

how did that cause an rpm dependant vibration?

H4Inf

got to love these easy fixes :-)

Kentetsu

If the exhaust system is not properly mounted, allowing it to rest against the frame rail (or any other solid car part) it will transmit amplified vibrations. The pulses of exhaust coming from the engine cause these vibrations in the exhaust pipes, which is why the system is mounted with rubber dampers. Make sense?

pimpncuba

that is what i figured would cause it, but i didn't think it would be that significant

Kentetsu

Yeah, it wasn't real bad, but thinking it was coming from the engine I was pretty concerned about it...

Dan_s_young

iTrader: (1)

ahhh, I have the same problem and it must be the same thing, I just installed my racing beat exhaust myself and didn't hook up some of the hangers because they were too rusted and stuff, I need to get it into a muffler shop to get them to fix the mounts up...

pimpncuba

when i installed my rb exhaust i didn't hook up some of the hangers and it made a kindof squeeking sound, not really a vibration

Snapshot

I had that for awile before my engine blew.

pimpncuba

shoo, go away before you infect my engine and it blows