Crank no start

Truck cranks strong won’t fire on its own, starts with brake clean, if I come back after sitting all day it’ll fire up and then die, trucks been sitting a few months, I put a new battery in it now this is happening, checked fuses, there’s fuel getting to the rails. It’s getting spark because it’ll fire then die (right?) bad fuel?, filter clogged?, not sure what’s going on with it, help is appreciated!

 

Year and mileage of your truck?

Welcome to the forum btw.

 

08 tundra 5.7 134xxx

 

It wouldn't be that out of the ordinary to need a fuel pump with that time/mileage (I have an 08 with about 126K). The fuel pump control module can also cause similar problems.

If you open one of the lines up by the fuel rails and crank the engine to try to start the truck, does gas spray out?

If it doesn't, you'll likely end up needing to drop the gas tank to test the fuel pump to determine if it is at fault or the fuel pump control module.

Testing the pump just involves powering it up with a 12V source. To test the control module, you'd want to see if it can power a halogen 12V headlight bulb that draws a few amps.

If gas sprays out of the fuel line that you open up while cranking, then you have a different situation where you've lost control of the injectors or the truck thinks there's a reason not to allow them to operate. That could be rodent damage and others may have experience with that kind of scenario and can chime in with what they've run into.

 

The theft deterrent system can enter "steal" mode even though its not being stolen. It would crank but not fire. If the battery in the ignition key has gone kurpoot the key cannot effect the electronic hand shake with the theft deterrent system that tells it "I'm the proper Owner's key. Authorize the fuel pump and start me up."

 

Bad fuel would be my first bet. Start simple, work your way up.

 

Hi Gabriel1229. So my 2008 5.7 with 154,000 miles has been doing something similar. Intermittently, it will take 5 or 6 starts to get it to stay running. When it first happens, the truck will start and the RPM's will come up, but then the RPM's will immediately fall to 0 and the truck will stall. Sometimes, the second try will just crank and crank without starting. I then take the key out, wait a second, put it back in and try again. It will start, but the same thing will happen. RPM's up then immediately fall to 0 and stall. I try to give it a bunch of gas during the start when this happens. I can get the RPM's up above 4,000 but they won't hold, they will pretty quickly fall to 0. Usually about the 5th or 6th try, something changes and the truck starts, I floor it, and then the RPM's slowly come down to idle and it runs just fine.

This has happened with low fuel in the tank and with plenty of fuel in the tank. It has happened in both cold and warm temperatures. When this first happened, it didn't do it again for about 6 or 8 months. So they were far and few between. But here lately, it's happening once or twice a month. It seems like most frequently it happens after I start the truck and then shut it off within 30 seconds. Then when I try again, it doesn't want to start. This isn't how it always happens, but more times than not. I get no dash lights at all when this happens. The truck starts and everything is as normal with no warning lights.

I keep forgetting to take video of the problem when it happens. I'm going to get good video next time. So the other night, I hooked up my OBD scanner just to see if there were any codes. There were. I'm getting a current and history code of B2799. This code stems from the engine immobiliser system. From the research I've done, it looks like this can keep your truck from starting. There is a range of problems that can cause this code. I'm still in the diagnosis/troubleshooting phase so I don't have any answers yet. I'm curious, have you had a scanner hooked up to see if you have any codes?

 

Check your ignition fuse & try firing the truck with another key.