Very troublesome issue no one has been able to diagnose
I've got a 1992 STX, automatic. She went on an adventure thanks to someone stealing her, and now I've got something going on in the front end that I'm ready to pull my hair out over.
When I reach 55+mph, usually after having to floor it either to merge or go around some slowpoke, it feels like either I have a flat or the front end is coming apart on me. I can feel it in the steering wheel and not just the front end. Stopping makes it feel like my rotors are badly, badly warped - felt in the brake pedal also. Once I've sat for a minute, it goes away. No shaking, no bad vibration in the brakes at all. Drives like normal. It doesn't do it consistently, really.
My brakes have been done very recently. Rotors are fine.
Tires are balanced and have been rotated recently also.
Tie rods, axles, struts are fine. Everything is tight. Motor mounts are good. Front end has been aligned, rack is new.
The roomie brought up fuel pump issues, but that wouldn't make my brakes vibrate like they're coming apart when I stop I would think.
Can anyone here advise what to look at next? I've had this car since 2006. She's taken me a lot of places, and I'm by no means ready to give up on her yet.
Thank you in advance!