GrnHrnt

You are right,the cap marked "H" is the high pressure port. Low pressure port,cap marked "L",is on the passenger side of the engine compartment, close to the firewall. Not easy to spot,but it's there.

The symptoms you describe might indicate a blown head gasket. Repairing a blown head gasket on a 2JZ is a lot cheaper than swapping in a used engine. A good mechanic would check for this before proceding with an engine swap. IF you could find a new factory 2JZ engine, it would be cost prohibitive for an 8 year old GS300. Used engines are readily available. Don't waste your time looking for a new or used stock all aluminum 2JZ engine.They don't exist. All 2JZ 's have a cast iron block with an aluminum cylinder head.

Factory stock SC300, sold in US, has a 2JZ-GE motor.

Inspect 10A "Gauge" fuse on J/B No 1, behind drivers side footwell kick panel. Panel is outboard, next to your ankle when your left foot is on drivers footrest pedal.

Check street side of airfilter housing and plumbing. Favorite place for rodents to set up housekeeping and completely block air flow to engine. They also like to snack on wiring and hoses.

Suggest you solve engine overheating issue before heater blowing cold problem: Did engine overheating appear suddenly or has been getting slowly worse for a longer period of time? Radiator clogged or its front blocked by leaves/newspaper? Radiator is completely filled when you inspect on a COLD engine? Coolant is clean with no visible oil? Drive belt is right part and it is correctly routed around all pulleys? Drive belt is correctly tensioned and not slipping? Thermostat is installed for correct flow direction?

All SC300 and SC400's left the factory with an open differential.

Steering wheel movement should be smoothly transmitted to rack and pinion input shaft. Check steering column for binding and inspect two "universal" style couplings on steering column.

All SC300's and SC400's were made in Japan. Non were made in USA. If your frame number starts with "0", it came off TMC's Motomachi assembly line. If frame number starts with "1", it came from Kantos Auto Works, Higashi Fuji Plant.

Can the low side port be in different locations on different years/models? Just looked and found the low side port on a 2000 SC300 about 6 inches forward of passenger side firewall. :)

Check 15A "CIG" fuse on junction block, located behind driver side kick panel. It's along side drivers left ankle when seated in driving position.

the shims were there but the springs werent, would this cause it to squeal without breaking? Factory manual for 2000 SC3 and 4 shows each front axle brake caliper has two ANTI-SQUEAL SHIMS, two "INNER" ANTI- SQUEAL SHIMS, two ANTI-SQUEAL SPRINGS and four PAD SUPPORT PLATES. Your year could be different, but if factory put parts on caliper and parts are called ANTI-SQUEAL .............., they are there for a good reason. A parts drawing for your model year should show if similar parts needed for your model and how they fit on brake assembly. Problem Symptoms Table in same secton of manual lists missing, broken, damaged or incorrectly installed shims and springs as suspect for "Noise from brake". The ANTI-SQUEAL SPRINGS look as though they help hold pads slightly off rotor surface as wheel is turning. Missing springs could seem like dragging brakes? Poor gas mileage? Cause of squealing without braking?

Were all the anti-squeal shims and springs and pad support plates on the calipers when you replaced the pads? Did you apply grease to the recommended points on the calipers?

Many things can make an engine stall and refuse to start. Some simple- out of gas. Some complex- broken timing belt. What made you suspect a bad fuel pump?

1)OEM stands for Original Equipment Manufacturer. Lexus parts will say "Toyota Genuine Parts" on the package. 2)Several fast,reliable Lexus dealers available online for parts. Realize brake rotors are heavy parts and a good price online may not be so good with extra shipping charges added to the bill. Park Place Lexus Plano often has good OEM prices for many parts. Need to shop around, prices always changing. 3)You can do limited mix and match with pads and rotors, provided manufacturers claim each part is designed for your application. Must replace parts on a per axle basis. Four new Lexus pads with two new, X brand, aftermarket rotors, all on same axle, is OK.