Please help...very lost
 

Ok, I just got a brand new aluminum radiator cause my stock on cracked...it took a week to get it and put it in and ever since my car has been shaking badly. When i start it up it shakes like crazy but once it warms up its not as bad. When im driving it shakes but only from 1000rpm to about 18000 rpm. I thought it might have been the clutch but there is no chatter or anything on the pedal. so i kind of dismissed that notion. i am going to take off the flywheel cover and see what its like in there but before i got started i wanted to post and see if anyone could help...anything would be greatly appreciated

wasnt doing it before?
 

so it started after the radiator install??? and also does it have an eletric fan or the regular stock fan???

Yes, it was after the radiator amd whats weird is i didnt touch ANYTHING but the radiator. Its an electric fan i got from a limo

Sounds crazy but check you Harmonic balancer, mine went bad a month ago and now one of my buddies is also going bad.

I lost a blade off of my Black Magic and the car vibrated every time the fan turned on. Are all your fan blades intact?

I already changed my harmonic balance about 3-4 months ago but i checked it anyway and it was fine...as for the fan idea...all the blades are connected at the ends. in my old car my rear main seal leaked and went all over my flywheel so my clutch was having a hard time catching. i had to take it all apart and i just hope i dont have to again. anyone, someone help me please?

you got me man sorry:confused:

Could it be a misfire? You could try checking the spark plugs to make sure there's no coolant on them and that they're not fouled out. You could also try disconnecting and grounding individual spark plugs to isolate if there's a cylinder that's contributing less. Since it's not as bad when it warms up (air/fuel is easier to light when it's heated up) that's why it sounds like a misfire.
If you check the plugs you might as well do a compression test to make sure you didn't blow anything. How old are the plugs and wires?

Great, now thats a start. I mean I hope thats not it but its defintely a start in a new direction. The plugs and wires are stock as far as i know. ive only had the car for about 10 months now. Wow seems a lot longer, but anyway. i got 2 days off in a row so that will be my project. THANKS!!! and ill keep ya updated

Moisture in the distributor cap.

very well could be a misfire. I had a kind of shaking problem and i thought it was like a motor mount or balancer but it turned out to just be a misfire.

It's easy to diagnose the difference in a balancer vibration, misfire, or driveline part?
hold the throttle kinda high about 3k plus while parked in neutral or parked, watch the tach, if it stumbles then you have a misfire, if the car shakes at a stop, it could be the balancer, if it vibrates while rolling not in gear, then it's a u-joint.

Another thing i just noticed is that you have a 255 lph fuel pump. I don't know when you installed that, but after i installed mine i got a severe misfire at lower rpms, hard to keep running cold and when it warms up to operating temp it mostly goes away.
Anyway, after checking fuel pressure and seeing 85 psi no matter what the adjustable regulator is set at, i disconnected the return line and ran a hose into a bucket....fuel pressure dropped to 35 psi and the car ran fine. I reconnected it and disconnected it at the fuel pump and the pressure went back up to 85 psi, the return line was restricting flow and sending out my 30lb/hr injectors (30lb/hr flow at 85 psi....that's alot of fuel!) 255lph is too large for the return line size of 5/16 (i believe that's the size) so i now have to buy new AN fuel lines, fuel pickup and fuel rail to run the 255 lph pump.