Lexus Repair: 93 Lexus ES300 low idle/shakes at stop or park, quality replacements, head gaskets

Question
Hi- 93 lexus recently started to shake while at a stop sign or in park (worse when at a stop) - idle was very low. I checked out some of your answers to past questions and took it to a mechanic - they replaced the idle air valve, cleaned the throttle, and changed the ECU (or maybe it was the EGR). Car ran smoothly for a few days but, now it's having the same problems. Low idle, shakes at stop or park (feels like it might die or stall), also feels like it's having a hard time switching gears - not sure if it's from 1st gear to 2nd gear OR from 2rd gear to 3rd gear - shakey (kind of sputters) when switching gears and almost feels like it's not getting any power. Can't figure out what else might be causing the problem. Do you think it has anything to do with the head gaskets? Can you help? Thanks!!!

Answer
Warm the engine & do a compression / leak-down test.
Record the data for each cylinder & lemmie know.


Check your ignition timing & change the plugs. NGK, or Denso only. While you're changing the plugs, might wanna think about checking the plug/ignition wires (Please only use high quality replacements, no parts stores, or Bosch bullshit). And changing the distributor cap & rotor.