Over the past several months, my '08 IS-F has exhibited several instances of "false starts" where the car will crank, attempt to start and then immediately die before I get my finger off the switch. The car will start normally after a 2nd attempt at starting. Anyone have any idea what's going on and where to look? Thank much!

 

I have had mine do this only once in a year of ownership. I bought it brand new.

A couple of questions....What brand and octane of gas are you using? Do you use any gas additive like octane booster or fuel injector cleaner?

 

I haven't had this issue but I have had several times where it seemed to hesitate and crank a couple more times than usual. The latest couple of times I have had this happen when I got to 1/4 tank my Check Engine Light, Check VSC, and traction control light came on. I tightened the gas cap which I don't get how it was loose since when can only turn it so far and get one click and then reset my ECU. I haven't had the issue since and also the lights haven't returned.

 

Three years on a five year battery?

Yeah, I've had a few of the slow starts lately, a couple of extra cranks before it fires, but none where it dies after catching.

 

Just had my battery replaced under warranty.
I eventually had to use my jumper box every time I wanted to drive her.

 

I had this problem a couple of months ago, I thought it was caused by the cold winter (well, not that cold down here in Miami). I took the car to the dealer, keep in mind that I got my car brand new back in June 2008. After inspection the dealer told me that my battery had a dead cell, they replaced it under warranty.

 

It's happened to me a handful of times. It seemed to only happen after I hadn't started it for while (week or two?), and I might have played my aftermarket stereo with the ignition off as well, so the battery charge might have been low.

 

In my experience, stock T/L batteries are not that robust. Both RXs, my second SC, and my GS ALL would require replacement (generally due to dead cell) within 3 years. Tempted to upgrade but my dealer was generally pretty generous with the pro rate.

That said, there's generally not too much warning. Week or so of slightly slow cranking (sometimes hard to catch since the motor fires so quickly), maybe some displays act up, and then.....................................that sad sound of the starter solenoid clicking away.

So much of our vehicles are computer controlled that voltage instability when battery dying produces wierd symptoms at times. But not for long............

 

Strange. That's not been my experience at all with a pretty vast array of Lexus/Toyota/Scion vehicles. I've always had great experiences with the OEM Panasonic batteries. Five to six year service life has been the norm for me.

The thing I know for certain about all batteries - the more "high performance" they are, the less they like to sit. If you use your battery daily (or very close to it) you'll get maximum service life. If the vehicle sits for extended periods of time, even with a battery tender, the battery will die sooner than you'd like.

PulseTech makes chargers that actually recover batteries with dead cells because the usual culprit is sulfation and their chargers can reverse sulfation (this is not just a claim by the manufacturer, I got independent confirmation this technology works from the Air Force while I was on active duty.)

 

^^^ I was about to upgrade my battery on my own but decided to stop at the dealer and have it checked, that's when I got it replaced. My battery was 2.5 years old and I didn't pay a penny for the replacement, it was covered under warranty in full, no pro-rated charges like in other car brands.

 

Roger that. These were all daily drivers. And now that I think about it, tho, the GX has not required replacement.

And I agree with your remarks re sulfation. Bought charger in the last year (name escaping senile neurons currently) with reverse-sulfation capability. Just haven't had occasion to try that yet!!

 

I've had that happen to me as well many times. It seems to only happen on particularly hot days in the summertime. I haven't had any performance issues due to these false starts so I think your ok. There's been another thread about this issue before if you want to look there for further info.

 

I bet the false starts are because the battery level gets so low it resets the ecu.

If you'll go out and pull your ecu fuses, wait for a bit, then put them back, I can almost guarantee it'll do the false start thing you mention.