Need Help To Resolve Cold Start Problem

[Phua]

My Lexus Rx350 (2007) having problem starting the car when the engine is cold or switch
off more than 1-2 hours. I need to crank the car at least 2-3 times to get the engine run.
Once the engine run, i have no problem restarting the car with a single crack.

Regards Henry

[TomC]

Foot off the accelerator when starting, right? I'd take it to your trusted mechanic. Good luck!

[jetfixer01]

Sounds like you are losing fuel pressure. Try turning the key on for about 5 seconds then off without going to the start position. Do this a couple of times, then see if it starts right up. When you first turn the key on, the fuel pump starts running. If the system is not keeping pressure when it's off, it will take a bit of time to build that pressure up. If you go to start immediately, it might not run. You can prove if this is what is happening by turning the key on and off a couple of times to let the pump build pressure. The pump will not keep running for more than a few seconds if it does not detect a start. That's why you have to cycle the key a couple of times to build pressure.

[eugene.s]

The problem may be caused by a variety of reasons - the plugs may require replacement, fuel system may require cleaning or other hardware defects, including poor fuel pressure as advised before (though, this is probably unlikely as you'd have some lights on on the dashboard in such case). Most of problems can be diagnosed electronically (i.e. without having to get into the engine compartment) - try getting to a dealer or a good electric mechanic.

[Phua]

Car was serviced with Spark Plug replace, oil, filter change and no detection of electronic fault code from a plug in tools.

My mechanic suggested to replace the “Fuel Pressure Regulator & Fuel Return Jet Tube Assemble” location in the Fuel Pump Assembly located in the Fuel Tank.

[eugene.s]

You need to tell us more. After which events did the problem arise?

(in particular, after or before the mentioned service)? When was the service done and what else was done during the service? Before the problem arose, did you take fuel from any gas station which you've not used before?

Is you battery good enough? The simplest test: in dark time: after having the engine off for 5+ hours, try the ignition "on" (but don't yet start the car), turn on your headlights while the ignition is "on", and then start the engine while watching at your headbeams. If the beams from the headlight get much worse during the ignition (compared to the beam while the ignition was in "ON") - probably it's the poor battery. Some batteries have an "eye" on them for checking their status. It look like a round looking like "glass" at the top of the battery. Looks like such batteries are not commonly used in the States, but if your battery has an "eye" - look at it (if green = good; if black of red, depending on the make = needs recharge; if black = replace the battery).

If nothing helps - try some good electric/mechanic. Indeed, the poor start may be caused by a variety of reasons (to add to the aforementioned, the starter, compression level, etc.) - but most of these should be easily checkable during computer diagnostics...

[RichQcCa]

Pua, were you able to find the issue? 

[DebB]

My Lexus RX350 2017 is not starting properly. A few days ago, I was driving, and the screen went purple and then black and reset to normal. After driving home we had a snow storm and so I did not use it for two days. On  the third day it started right away and I was able to drive it but at the end of the day it did not restart. First I replaced the battery on the key fob. That did not help. Then I jump started. This worked and I was able to drive home but when I turned off the engine I could not turn it on again immediately following turning it off. Thoughts on what the problem could be? Thanks!