Hey all,

This is my first post but I've been on many many times as I bought an 03 SE7 in October of 19. I have run out of ideas for what could be next on this shaking issue. Like many threads before I have shaking at 30mph at about 2100 rpm, deep shaking, then it tapers off around 45 to a quicker lighter vibration. Nothing when I let off gas. Seems like very faint miss at idle maybe. Nothing at all before 25-30. I put in new iridium plugs, nothing. I put in the front drive shaft from Lucky 8, no help (but good to know I'm not tearing up the transmission!), yesterday we tore out the intake manifold and change coil packs and wires that I got from luck 8, (seems a little better but definitely still there at 30mph). I do not know what to do next!

Thank you all for any advice!

 

get a code computer and look for error codes/misfires.....

Driveshaft imbalance?
Harmonic balancer rubber falling apart?
Wheel balance?

 

It did say 1 and 7 misfire which is why we thought coil. We cleared codes to see what shows up. I'll let you all know. The shaking is not in the wheels like a hub or tie rod.

Thank you

 

Broken trans or engine mounts?

 

This makes sense. Checking the engine mounts is easy -- just use a bottle jack or a floor jack under the oil pan (cushioned by a piece of wood) to raise the engine and see if the mounts separate.

 

The oil pan is pretty stout, but still cast.
It would be better to jack under the crank pulley.

 

Possible you shock absorbers , the problem is they as so heavy you can just push the wing down a check the bounce but it easy to take them off and and then full stroke them in and out to see it there is any give, when in the full in and full out positions, if one if lost gas /oil it will bounce more than the others
also lets not forget some thing a simple a wheel balancing if the weights have come off your wheels will vibrated out of balance, always best to check the easy inexpensive stuff first

 

Is it MPH related, or RPM related (both were mentioned)? If it's a problem when only on the move, try different gears (thus different RPMs) to see if you get a change in behavior.

 

spark plug wires would be my guess. coil packs are pretty robust. torgue converter lockup at lower speeds loads the engine and will induce missfire

 

New coil packs, new spark plugs, new wires. I'm thinking Fuel pump, revs fine in neutral but flooring it in drive only gets to 3000 rpm. Feel like it could be struggling for fuel. Seems to be the next step. People are saying that is a common fuel pump symptom? I'll look at mounts, struts are newish. Do have a p0126 code so a new thermostat will be going in also. Could a fuel pump/clogged filter or a bad thermostat cause the engine to go into a "limp mode" during driving so no more damage is caused?

Thank you all!