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Discussion Starter · #1 ·
I have 2018 Platinum with 55,000 miles. In the past three months I have experienced a starting problem. It occurs on cold starts and warm starts. The engine will crank and not fire. Sometimes it starts after I turn the ignition switch once or twice. Sometimes I have to turn the switch 12 to 15 times. After it starts it runs perfectly. I took it to my dealership and they ran a diagnostic on the truck. Diagnostics show everything is working properly. Has anyone else experienced such an issue? Can anyone point me in the right direction? Frustrated…
 

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Discussion Starter · #3 ·
Allyotas thank you for the information. The truck is a flex fuel vehicle. I have not used E85 at all. I am curious why the vehicle is not throwing a code as the Toyota TSB is alluding to. How can I determine if my motor is a 3UR-FBE engine?
 

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The motor is virtually identical between the flex fuel and non-flex fuel vehicles with a few peripheral changes; the pump, iirc, is different to flow more fuel if running e85, as are a few lines and sensors. What sometimes happens with the flex fuel setups is the ethanol sensor erroneously tells the computer that you are running e85 when you are not; the computer then dumps way too much fuel in to the motor. Usually, folks notice a sudden decrease in mileage by several MPG’s. Their scanner can/should have shown fuel alcohol percentage but sometimes they don’t pay attention to it. There is a pcm update but that should have already been done (though you should verify). Second thing is to unhook the battery for 10 mins or so, then reconnect and restart. This allows the computer to relearn itself.

A few other things: are you using the original key? Or a reprogrammed one? Did they check fuel pressure at the dealership? A failing fuel pump can cause low pressure and non-starts or stumbling starts. Do you let the vehicle sit for several days/weeks in between driving it? The ethanol in fuel is hydroscopic and deteriorates fuel quality quickly. Poor quality gas can cause the same issues. Do you fill up at Costco or Walmart? :D
 

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^^ the tsb states you may not have the light. And it would be my guess that the tech was only looking for trouble codes not at actual running parameters. Fwiw I've had thus occur once on my 17. My ethanol % is stable at 20%-ish but I'm running a tune and nit sure if that was something they tricked for it (only monitoring the ethanol for a few months now)
 

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Discussion Starter · #6 ·
I do have the original keys. The technician at the dealership stated the fuel pressure is good. I was asked if I use e85 fuel. I do not. I fill up at Speedway gas stations in the Indianapolis area, and when on the road out of town I stop at Pilot truck stops if no Speedway gas stations are in the area. The issue presents itself on cold starts as well as warm starts. I have disconnected the battery and let it sit for several minutes. I will see what affect this has. If not corrected I will take it back to the dealership with the TSB in hand. Thank you for all of your input.

I had a 2014 Platinum for 4 years and put a 135,000 miles on it and never had this issue or any other issue with that truck.
 

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I've had this same issue for years and years. Non-flex fuel 2009 5.7. I even replaced the engine due to other issues, still have it happen sometimes. I've replaced the starter, charcoal canister, fuel pump ecu, fuel pump relay, fuel pump, key; everything. No codes ever. Technicians think the only thing left to replace that could cause this is the chip key receiving unit (immobilizer related) which is supposed to be over $1200 parts and labor due to being hidden in the dash. Next time it happens, as it's turning over, try tapping the gas pedal a few times, should make it wake up.
 

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I've had this same issue for years and years. Non-flex fuel 2009 5.7. I even replaced the engine due to other issues, still have it happen sometimes. I've replaced the starter, charcoal canister, fuel pump ecu, fuel pump relay, fuel pump, key; everything. No codes ever. Technicians think the only thing left to replace that could cause this is the chip key receiving unit (immobilizer related) which is supposed to be over $1200 parts and labor due to being hidden in the dash. Next time it happens, as it's turning over, try tapping the gas pedal a few times, should make it wake up.
I have a 2008 Tundra. I had this problem and I would disconnect the battery and reconnect and it would start. Turned out to be the chip key receiving unit. Had that replaced about 150K miles ago and have not had a problem since.
 

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Thank you for confirming my suspicions! If you do not mind sharing (for comparison purposed to what I was told), can you please tell me the approximate part cost, labor cost (of the chip key receiving unit), and what state you are in?
 

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Thank you for confirming my suspicions! If you do not mind sharing (for comparison purposed to what I was told), can you please tell me the approximate part cost, labor cost (of the chip key receiving unit), and what state you are in?

It cost $1200, (labor was $918) which included reprogramming the keys. I live in NH. The dealer called the part a Transponder ECU. They had to remove the dash as stated above.
 

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Thank you very much... I guess what I was told was right, and it's not one of those jobs that just any mechanic can do, pretty much has to be dealer to get it done right
 

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Discussion Starter · #12 ·
Well the 2018 Platinum finally wouldn’t start. I disconnected the battery on 05-17-2021 and left it sit for 30 minutes. I reconnected the battery and did not experience that first issue until 07-09-2021. On 07-09 the truck wouldn’t start. A flat bed delivered the truck to the dealership. I mentioned the TSB listed in one earlier reply. They took note of it and ordered the new fuel pump. Not the issue they say after checking the fuel pump. They also investigated the system for issues regarding E85. Not the issue. They are struggling to figure out what is going on. They have called the “Master Engineer” in the region. I hope this person has good diagnostic skills. The truck has not thrown a code. I have original keys. I use quality fuel and do not use E85. A little frustrating to say the least. Any further ideas?
 

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Probably not related but I had an an issue with the immobilizer on my 2016 CM with 70K miles. My windshield had been replaced and was not sealed properly on the passenger side. As a result, water had leaked and caused a malfunction of a relay or sensor which was located under the trim on the front passenger side door well. This caused the immobilizer to activate. Once the window as re-sealed and the relay/sensor was replaced it fixed the problem.
 
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