Lexus at turtle speed

2001 Lexus GS 300

So, going to work, pulled out of driveway in reverse. Put the car in drive, and it didn't want to go more than 5 miles an hour. Headlight were very dim. We drove it 1/4 mile to see if it would decide to act right.

Must mention that the car DOES have an unidentified trickle drain. We have the battery on a quick connect terminal, and it gets disconnected every time it is in the drive way. The battery is only hooked up for driving and while in a store shopping.

Thoughts? Wild guesses?

Can't remember...standard or auto trans?  Gas or diesel?

Auto trans could be low fluid level in the torque converter.  

Low volts could be causing an issue with fuel injectors, but those usually just won't fire at all if below a certain volt level.  I have had an Accord that did that to me once due to bad battery.  Pulled out into traffic and it could not get out of its own way.  If a fresh battery does not fix it, it is likely in the fuel delivery system; but let's not get ahead of the curve.  

I should also mention that if it is due to a bad battery, the alternator is also suspect at this point.  It should be producing enough charge to keep the car performing.  Check to make sure it is generating a sufficient charge.  It may jut be the battery is a weak link in the system and the charge is getting derailed between alternator and fuel injector.  Replace the battery first.

How many miles on the car?

Are you able to 'rev' the engine to higher RPMs in park?

Did you have to rev it to get it to go 5mph? Seems to me it should go that speed at idle.

Did it act 'normal' in reverse?

I'm no expert on Lexus, but it might have gone into a limp mode for some reason. Or could be a problem with the torque converter.
I'd start by checking the tranny fluid level. Does it look clean & red, smell burned?

So many things to look at. Transmission shift solenoids, low ATF level, Knock sensor, air/fuel ratio, low voltage, battery at the end of its life cycle. Time to run the OBDII and look at the codes to get a starting point.

This one is an automatic transmission.
Gas engine.
Maybe 200,000?

Where would I get the diagnostic reader?

Would this be the proper place to get the code meanings?
https://obdii.pro/en/model/lexus

 low ATF level

Huh?

Joylynn Hardesty wrote:

 low ATF level

Huh?

Automatic Transmission Fluid.

Joylynn Hardesty wrote:This one is an automatic transmission.
Gas engine.
Maybe 200,000?

Where would I get the diagnostic reader?

Would this be the proper place to get the code meanings?
https://obdii.pro/en/model/lexus

I got a $10 diagnostic reader on sale once, many auto part stores offer to read your codes for free. A mechanic could also do it. Essentially the device plugs into your car underneath your dash and gives you a code or codes. You can then look up the code and your car to see what it means and have an idea where you should look for an issue.

From O'Reilly's would it work?
https://www.oreillyauto.com/detail/c/innova/tools---equipment/diagnostic-tools/code-readers-scanners/5609f7011617/innova-obd-code-reader/inn0/5010?q=code+readers%2Fscanners&pos=0

Low Automatic Transmission Fluid level. Most parts stores in my area will let you use a OBDII reader in the parking lot. An OBDII reader from Amazon or e-bay can be picked up for 30.00.  Once you get a code if the reader does not identify the issue a simple Lexus PO#### search will identify the problem they always start PO####.
The O'Reily reader would be just fine.

Howdy,
Look up,    auto diagnostic code reader

I bought one of these,     https://www.harborfreight.com/obd2-code-reader-64981.html?gQT=1

I was given a 1998 Subaru legacy outback w/AWD.  Leaky head gaskets at 174,000 miles. I replaced them myself, among other things. I should be able to get over 300,000 miles on this vehicle. I do most of the mechanical work myself. This is the first total computer sensor vehicle I have owned.  These new vehicles need a good strong battery to work. That is where I would start.  After all the work I have done on this Subaru, the "check engine light" is still on. Car runs very well and I get 22-23 MPG. Do the easy stuff first.

I would check the alternator. The hint is the dim headlights.

Oops, I just saw that Jack mentioned that already.

Joylynn,

Sorry for the short response.  I was at work.  Tonight if you can pull the battery and take it to your local parts store.  Have them bench test the battery.  Ask if they can do a load test and determine if there is a bad cell.  A damaged cell in the battery can cause the trickle discharge you mentioned.  When one cell is bad the surrounding cells in the series will try to balance the charge.  This causes a loss of charge.  The store will tell you if it is capable of holding a charge after they run it back up and do a load test.  A good tester will also identify if a cell is bad.  If the battery passes the load test, then your alternator needs to be bench tested (or replaced) next.  The same shop can do a bench test but it will have to be off the vehicle.  

If the battery is good (before you pull and test the alternator) ask if they will hook up their scanner.  They can pull the code and tell you what it means from the internet.  a Google search for the code will give you a lot of information.  It will save you some time.  

If the code comes back as a non electrical issue, then my guess would be to check your transmission fluid level and smell the dipstick for any burnt or foul smell.  ATF usually is strawberry/cherry red with a sweet smell.  Dark, black specs or smelly indicates a problem.  Low level just means it needs more fluid to in the torque converter to transmit power.  Let us know what you find and we can go from there.

Joylynn Hardesty wrote:From O'Reilly's would it work?
https://www.oreillyauto.com/detail/c/innova/tools---equipment/diagnostic-tools/code-readers-scanners/5609f7011617/innova-obd-code-reader/inn0/5010?q=code+readers%2Fscanners&pos=0

That would do what you would want yes.

Do you have a multi meter? If you do rather than having to remove the battery or alternator, try this: What is the voltage of the battery after sitting overnight disconnected? With the vehicle running what is the voltage at the battery? With the vehicle running what is the voltage coming off the alternator large post that goes to the battery?
A healthy battery after resting should read 12.65
At the battery with the vehicle running the voltage should be at roughly 13.5
At the alternator the reading should be that 13.5 too.
So after resting less than 12.65 at the battery, pas bien. Might be a little less depending on the batteries age.
At the battery while running less than that roughly 13.5 it's not getting charged. Bad alternator or an issue with the wiring from alternator to battery.
At the alternator if it is showing that roughly 13.5 alternator is good. 13.5 at alternator but not at battery wiring issue.

If it started, your battery is good enough. It might test bad on a battery tester, but isn't a concern as far as this diag is concerned. Your alternator may not be charging, though, which can be verified with a voltmeter. You'll want to see a little over 14 volts. I'd guess the source of your problem lies there, based on the dim headlights concern
.

If not though, you'll need to have codes checked. You can get this done for free at the local auto parts store, and go from there.

Your vehicle uses an electronic throttle body, meaning your gas pedal isn't directly connected to the throttle assembly. The computer sees how much the accelerator pedal is being pressed, and then commands the throttle assembly open or closed based on that, using an electric motor. But, the computer can ignore the command, if certain conditions exist. For example (and I'm not saying this is the case with your vehicle, this is just an example) the computer may see that the transmission is slipping, and will only allow the throttle to open no more than 5%, or not go over 1500 rpm, to prevent further transmission damage.

One other thought......is this the car that recently had a thread about brake replacement? It's not out of the realm of possibility that the brakes are locked up, keeping the car from being able to move very fast. It would be fairly obvious, as the engine would sound like it's trying to accelerate.

We'll investigate all suggestions tomorrow. Thanks everyone.

And yes, the same car, James.

Socks before Shoes. Do the simple things first. The charging issue may have nothing to do with limited acceleration, but you need to address it eventually. Check the ATF level. Check to see if a caliper is hanging up as James suggested.

Update

Transmission fluid is at p[roper level and does not smell burnt.
Brakes seem to be fine. Thanks for your confidence in my workmanship.

It started with a hiccup today. It was slow to get moving, both in reverse and first gear. We went to grocery store, paused at door for me to get out and the damn thing stalled. He put it in park to restart. It would not. At that point it was stuck in park, unable to get it in neutral to push it out of the way. Sigh. Good samaritans helped us out with a jump, we got it going and sped home.

So, no groceries, no stop at the parts store. Hunny has decided it is the alternator.

Current plan, multimeter, code reader and alternator are ordered. Will beg ride to autopart store when they are ready.