Both my code readers have an option for "pending codes". Did you try that?

 

I have a cheap OBD2 reader - not sure if it has a pending codes option, but I'll take a look!

 

Did you fill up the car since you brpught it home? Don't know how long the car was sitting waiting to be sold. There is a chance
condensation formed in the tank. I'd por some gas line anti-freeze into the tank. If battery is weak your head lamps or dash illumination
will sort of scintillate. I live in cold weather in winter. I always use some gas line anti-freeze for all my family cars and never let the tank
go too empty between fill ups.

 

Could still be the battery. Connect a charger/jump starter to the battery and try to start the car. If it starts first time with no issues, then it probably is the battery.

 

Has the battery still not been checked?

 

I haven't checked battery yet as I've been working, but hope to get a chance in the coming week. I did get a chance to check pending codes tonight with my generic obd2 reader.... nothing.

When you put your foot down to accelerate in these cars is power immediate and smooth / linear or does it seem to bog down and do not much for a couple of seconds then surge in with a strong wave of power?

Thanks.

 

The 2007s (and some later cars) had issues with the transmission software. There was a TSB about this but updates were only provided for cars still under the original 4/50 warranty. You'll have to pay for it now, if needed.

 

Had the battery tested with a Bosch BAT-131 EMEA...

Battery test
GOOD, RECHARGE
voltage: 12.30v
measured: 609 amps
rating: 840 amps

Starter system
CHARGE BATTERY

Charging system
NO PROBLEMS
No load: 14.01v
Loaded: 13.92v

I have been driving the car daily 30 miles per day for a week, with a 60 mile trip yesterday, so the guy said you would expect the battery to be fully charged after all that driving.

So the question is, could this 609amp output rather than 830amp it's supposed to throw out be causing the car to struggle to start sporadically? It cold started this morning within about two cranks, no problem, yet other times immediately after driving a good distance it can struggle to catch... wouldn't it be worse in the morning after standing?

 

If its the battery, it should be worse after an overnight sitting.

 

So I still haven't sorted this problem... started fine this morning, then coming out of work was worst yet, took three presses of the start button, cranking around ten times each press and not a single sound of it trying to catch.

I am trying to work out what the next step should be...

Lexus said they would diagnose (takes about an hour workshop time) but with it being intermittent might not find anything. The cost of this is the same as the cost of a new crank sensor or cam sensor, which I could happily fit myself.

Question is, would it be best to chance the money on the diagnostic finding something, or just replace the sensors (maybe cam first?) in the hope that it is a cam or crank sensor fault.

Any thoughts appreciated.

 

Are there any good independent shops that specialize in Lexus/Toyota in your area? Given what they are wanting for diagnostics, provided there is a quality indy shop in your area, it could save you a small fortune.

Moreover, often when a first time customer brings their car, these sorts of places often go the extra mile to earn your business. The ideal would be a shop founded or have an employee who was a Lexus Master Technician with all the attendant training.

 

Forget the battery rating - that has nothing to do with what you are experiencing. If the battery is fully charged, and it likely is, then there is probably something wrong with your battery, probably a defective cell. The fully charged voltage should be higher unless the battery is very old or has a defective cell. You can determine if it has a defective cell by testing the cells with a hydrometer, but unless your battery is fairly new you should just replace it. A new battery is not real expensive, they frequently don't last much over 40 months so replacing the battery is the thing to do to help move along.

 

Thanks, I actually have a big battery from a Rangerover in the cellar, so maybe I should keep it in the car for the next few days and use my jump cables to connect it to the car every time I start... it's gonna be tedious to do but I guess if the problem goes away or recurs when I do it will eliminate or confirm if the battery is at fault without spending any $$$.

 

The "big Rangerover battery" sounds like something I would do. I will try to give you the advice that I hope someone would give me. It's not a good idea, for several different reasons. Anything you figure out doing that will probably be ambiguous and, as you said "tedious" and it is risky and you shouldn't jump-start these cars except in an emergency.

Your starting difficulty may or may not be related to your battery, but the battery test information that you provided seems to me to indicate that your battery is defective. The Bosch BAT-131 is a high quality battery testing device so no problems there. However the data is troubling in that it indicates that the car's charging system is working properly but that the battery needs to be charged. You told us that your car has been driven regularly in a manner that should have charged the battery. And you mentioned that the technician was surprised that the battery was not fully charged. If indeed the battery is fully charged - the definition of fully charged is when any additional charging will not raise the state-of-charge - then the 12.3 volt reading is likely an indication of a defective cell or some sort of problem in the battery.

You should look at your battery to see who the manufacturer is, get on the Internet and find a battery dealer for that manufacturer and take your car there and have the battery tested. If the battery test indicates that the battery is bad then the battery dealer can replace it at a prorated price. Batteries are not like windshields, good until they get broken - they are more like tires, they wear out with time and use. Sometimes batteries have defects and fail prematurely. Nearly all batteries are warranted by the manufacturer for 36 months or more, against all failure, no exceptions and most will last at least that long in even the most abusive operating conditions.

 

I still dont see how the battery could be at fault. The car is turning over, which requires far more power than anything after that (fuel pump. etc). That said, I'd probably replace it as a preventative maintenance item, since it's nearing four years old.