Lexus Repair: Cold Start Problem on a 2001 RX300, 2001 lexus rx300, lexus rx300

Question
Conceptually, I understand throttle-by-wire but I must disagree that it doesn't matter how much I depress the accelerator...it won't start unless I press down on the accelerator, therefore it must matter.  Furthermore, it stalls if I remove pressure from the accelerator.  The symptoms remind me of my first vehicle which was carbureted and had a broken manual choke cable...give it gas to get it started and manually maintain the RPMs until it warmed.  I'll try cleaning the throttle plate and checking the fuel pressure but I have little confidence that this will reveal anything unless it's experiencing these uncommon symptoms.  I agree that it is rare that a Toyota experience fuel problems so soon.  I guess this is why no one can diagnose it for me.  Thanks anyway, Dean
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-----Question-----
I have a 2001 Lexus RX300 with 100k miles.  The vehicle normally starts and runs perfectly; however, recently I've experienced a hard starting problem when the engine is cold.  I've taken it to the dealer twice but they've been unable to replicate the problem and therefore have taken no corrective action.  It seldom happens making it difficult to diagnose.  The hard start only happens if the engine is cold and if cranked and driven only a short distance and turned off.  The next time you attempt to start the vehicle, it sometimes refuses to start.  You must depress the accelerator to get the vehicle to start.  Furthermore, you must maintain pressure on the accelerator to maintain sufficient RPMs until the vehicle reaches normal operating temperature.  There are no check engine lights or subsequent codes.  It seems to be some sort of choke-related problem.  I'm in the Army and deploying to Iraq again soon.  I'd really like to resolve this before I go.  Thanks for any advice, Dean
-----Answer-----
Your pedal has nothing to do with it. Your engine is throttle-by-wire.
It doesn't matter what the pedal says. Anytime the engine is cranking, or idling immediately after start-up. The computer decides how much to open the throttle, not you. There is no direct link.
(Well really it does that all the time, but during cranking. You might aswell not touch the throttle. You have nothing to do with anything in that particular process.)

Clean the throttle plate off with a brush & whatever penitrating oil / carb cleaner you like. If it has an idle valve, get that too.



Fuel problems are abit uncommon on Toyota's at such a young age, but if you want. Drive the engine till warm & check the fuel pressure. Then shut it off & check it 5 minutes later. It should maintain 25psi at the fuel rail.

Answer
Again. Your input has no bearing on what the throttle does while the engine cranks. Get your hunnie to step on it with the key ON & crakn it, with the itnake off. It'll do exactly what the computer tell sit.
As the engine has no idle valve. The ECU controls the throttle plate instead to maintain the idle.



Clean the throttle plate off really well.
If it's stuck with some carbon, the little motor will have a real hard time moving the plate around to get it to stabilize an idle / start at all.
Happens all the time. :)