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Discussion Starter · #1 ·
I am writing this just days after recieving my truck (2012 tundra) back from Toyota for going into LIMP mode and for having a faulty front actuator.

I get the truck back from Toyota, the next day I drive it maybe five minutes into town. It is parked for a couple hours or so, then when I try to start it it just continues to crank but nothing happens. I try this several times, then all of the sudden after turning it off and on and waiting, it starts. After I drive home, I turn it off and on several times and it starts no problem.

The next day I go to drive it again, and it wont start. Again I try turning it on and off several times and it just continues to crank over and not start. I am thinking it has to either be spark plugs or fuel. Sure enough, when I turn the key into the on position, without trying to start it, I do not hear that initial energizing of the fuel pump. I try pumping the pedal alot and do not smell gas. I check the fuel pump fuses and relays, they both look good. I am thinking that it has to be the fuel pump, and because I do not have a lift and cannot remove the gas tank, I get it towed to toyota thinking that the fuel pump will be part of the powertrain warranty.

By this time I had drained the battery super low so the cranking is slowly dying. Toyota gets the truck and says that they charged the battery and of course it starts right up. I tell them to let it sit overnight and try again. They do, and it starts right up. They are telling me they think the battery was not charged enough. It only had enough power to turn on some systems, but not enough voltage to power the fuel pump.

I am skeptical of this, as I am sick of getting stranded with this truck. Anyone think that this makes sense? I had this thing cranking for a long time so it seems like if the battery had enough power to do that then it should have enough power to turn on the fuel pump. If anyone is having this same issue, try charging your battery first.
 

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Discussion Starter · #3 ·
I originally tried a different key and all the different alarm spares that I had, I forgot to mention that. Most the time I used the same key however, which is the same key I gave to the dealer which worked for them...
 

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First off, pumping the gas pedal on a fuel injected vehicle that is not running will not make fuel go into the engine so you would never smell fuel. Spark plugs don't go bad one minute and then work the next. I can never hear the fuel pump on my truck..doesn't mean anything though. Unfortunately at this point you are just going to have to drive the truck and see if the problem reoccurs.
 

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I originally tried a different key and all the different alarm spares that I had, I forgot to mention that. Most the time I used the same key however, which is the same key I gave to the dealer which worked for them...
If it happens again get a battery charger/jump on and see if it starts up.
 

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Discussion Starter · #6 ·
First off, pumping the gas pedal on a fuel injected vehicle that is not running will not make fuel go into the engine so you would never smell fuel. Spark plugs don't go bad one minute and then work the next. I can never hear the fuel pump on my truck..doesn't mean anything though. Unfortunately at this point you are just going to have to drive the truck and see if the problem reoccurs.
I used to do the same thing with my motorcycle and thought I would give it a try.. Agree about the spark plugs. I have a repair Manual for the truck which says that you can here the fuel pump initialize but i have not got it starting consistent enough to test it out. Regarldless, I have been checking the battery voltage before I start it each time, and so far I have got it to start with measurement anywhere between 11.8 and 12.5. It has also not started with measurements between the same values, so what Toyota told me does not make sense. Also I tried jumping it with my car when it would not start and no luck. One other thing to note: when it would not start, I put it (engine off) in drive then back to park, at which point it started the next time. Thinking maybe there is some sensor off? Or still a faulty fuel pump which toyota told me they tested.
 

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I used to do the same thing with my motorcycle and thought I would give it a try.. Agree about the spark plugs. I have a repair Manual for the truck which says that you can here the fuel pump initialize but i have not got it starting consistent enough to test it out. Regarldless, I have been checking the battery voltage before I start it each time, and so far I have got it to start with measurement anywhere between 11.8 and 12.5. It has also not started with measurements between the same values, so what Toyota told me does not make sense. Also I tried jumping it with my car when it would not start and no luck. One other thing to note: when it would not start, I put it (engine off) in drive then back to park, at which point it started the next time. Thinking maybe there is some sensor off? Or still a faulty fuel pump which toyota told me they tested.
What about the park/neutral safety sensor??
 

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Discussion Starter · #9 ·
update: so I did not make any changes and it has not failed to start in about 8 days. New symptom now tho, when i start driving, usually when I am going down the freeway the trac symbol (little car with the squiggly line underneath it) comes on and the truck will not accelerate. It drops all the way down to about 30 mph, and then it kicks back in and accelerates. Usually happens about once every time that i drive. I do not even know where to start with this issue.
 

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Discussion Starter · #11 ·
ok so i think i finally got to the bottom of this, if anyone runs into this issue again. I have to give it to Ditchhooker, he answered me right away a few months back (
Try a different key, sounds like the anti theft chip is going t/u
and he was spot on.

I took the truck to Toyota again, and they took the dash apart and the tech there said he has been working on Tundras for 20 years and he has never seen such a complicated alarm security system. It took him a whole day to take it apart. He said that the security system was probably glitching and not recognizing the key that i was using (not stock). I guess the factory key has to provide a certain resistance or something when you insert it, and the previous owner had the truck modified so that it was able to recognize multiple keys. On top of that, there were bare exposed wires in the wiring that he said could be acting as antennae and taking in false signals.

My truck had been randomly cuttting out power while driving down the road, and he said that if the security system glitched while i had the wrong key, or if the bare wires took in a signal which got sent to the computer while driving, it could cause the truck to stop supplying power. Which i guess is to shot off the injection system, which makes sense why the truck was turning over but just was not starting.

I had the whole security system removed, and now it is working fine. Hopefully no one runs into this issue, ever. Thanks for all the tips.
 

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You never mentioned that you had an aftermarket security system in the truck. I'm saying aftermarket because there is no way to remove the factory immobilizer system. Also the factory immobilizer system will NEVER cause an engine running issue ONCE THE ENGINE IS STARTED. The factory immobilizer system also allows up to 8 keys to be registered. The immobilizer system on this truck is actually pretty simple. If the immobilizer system did indeed cause a no start condition a description of why it did it is stored in the system which makes it VERY easy to diagnose.
 

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The same exact thing happened to me. The dealer installed this theft system called "theft patrol" on my truck. They had the truck for a week and finally diagnosed that there is a compatibility issue with the two. They finally removed it and installed lo jack instead. I am now good to go.
 
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