I have been having sporadic problems starting my car... Sometimes it starts fine and sometimes it doesnt. I will try my best to explain what is happening.
When I have a problem, like this morning... I hit my start button (all normal lights come on), however, it just clicks several times and makes a very light spuddering noise and doesn't turn over. I always try it several times in a row and sometimes it will start and then sometimes it just won't for 15 minutes or so. I have never had an issue where I couldn't eventually get it started.
I have taken it to the dealership and an independent mechanic. I have spent money trying to diagnose the issue to no success.
My question is, has anyone heard of this issue? What could my potential issues be? I have had the obvious things checked...but this is really a bad situation for me because I can't rely on my car to start all the time.

 

Sounds like it's the car battery to me. But you said you took it to the dealership, what did they say about the battery?

 

Battery, spark plugs, coil pack, oil level, fuel pump, gummed up injectors, air filter, MAF, starter motor, fuel quality (didn't fill it with diesel by accident?), ECU.
I'd be on the phone to a couple of mechanics to gauge which one sounds like they know how to diagnose fully and correctly, before enlisting them to find and fix the issue(s).

 

I have a new battery... Its like these guys at the dealership just hook it up to a machine and everything is ok then they don't know what the hell is wrong with it.... so annoying.. Anyone know any good mechanics in Houston by chance?

 

you might want to try cleaning the battery terminal.

 

The symptoms you describe does sound like a battery issue to me as well. I had a dead battery a month ago. Had it replaced. Then last week it died again. Lexus mechanic did a battery test and showed me the print out, which showed that it's bad. So it was replaced under battery warranty. Maybe you can have it tested. Actually, does your car even start with a jump starter connected?

 

The dealership replaced the battery since it was under warranty. They said that had to be the problem....well it wasn't because this issue is still happening...

 

Is the started located under the intake in the back of the motor like old 400s?

Its not unheard of starters failing.

 

I would start with replacing the battery in your Key Fob assuming it hasn't been replaced. This can and will cause an issue...

 

Surely if the key fob battery was low voltage, the system would display "Key not detected".
A cheap enough test to prove it's not that, but even so, I'd be highly surprised if it boiled down to a simple fob battery on its way out.

 

^umm ok are you ready to be surprised

 

Absolutely - when the OP reports back that the new battery in his key fob has cured the problem.

 

Raidergrad,

Did you ever figure out your issue?
My 2006 GS 300 just started displaying this same issue.
I think it is bad fuel

 

Boron,

Wouldn't all the issues you name cause a check engine/VSC light and codes?

 

Not necessarily.

A battery with a cell or two on the way out, won't flag up a dash warning light - but it should be discernible by the way it struggles to start the engine.

Spark plugs and/or coil packs going, won't flag up a warning light.

In effect, until something fails outright as opposed to having degraded and on its way out, the ECU is still receiving some signal, and it will be entirely dependent upon what voltage Lexus engineers have programmed the ECU to flag as outside acceptable levels, and throw an engine check light, along with the corresponding fault code.

One presumes the dealer has checked for fault codes, and battery state of charge, etc before declaring they can't find anything wrong.
Would be interesting to hear from the OP as to what the culprit actually was, and whether I've to be surprised to learn it was only the key fob's battery all along.