Starting problem

Hi all. I’m new to this forum. Thanks for having me!

i have an 08 Taco with a 4 litre engine and a 6 speed standard.

I have an intermittent starting problem. By intermittent I mean 2-3 times a year.

This is what happens: I hit the key, the engine cranks over and starts but whe I let go of the key and it’s in the on/run position the engine immediately dies. It always has started and keeps running eventually. Sometimes you walk away for 5 minutes and try it again and it goes. Sometimes you disconnect the battery for a couple minutes and it goes ( but no always). If it would actually stay dead when the key is in the run position I could probably figure it out, but it doesn’t! Then it probably won’t happen again for months. It’s done it with the engine hot and cold. And of coarse it never happens at home where I have access to tools.
I remember several years ago There was similar starting issues with Ford pickups. The problem was an inertia switch that’s supposed to shut off the fuel on impact. Does anyone know if Toyota uses some kind of safety fuel cutoff device?

My other though is possibly a bad ignition switch not always making a good contact when on the on/run circuit.

Has anyone experienced this kind of problem before? It’s so maddening because it happens so infrequently. I can’t make it happen at home no matter how much I try. I’ve pulled on harnesses, shook the shit out of everything to try make it quit running. It’s never died going down the road, only on start up as I described previously.

Anyway all comments and suggestions are welcome. Thanks Everyone!

Doug

 

Does the security light next to the clock flash with the key on when this happens?

 

When it dies immediately do you still have dash lights like check engine, battery, ABS, etc or is it completely dark

 

All dash lights check engine etc are on. I’m not sure about a security light??? Not that I’ve noticed anyway.

 

Need to note the security light when it happens, if it flashes with the key on the truck isn't gona run.
The Immobilizer Module will typically set a B2796 and/or B2798 code if it can't read the key but the PCM will not set any codes for an immobilizer key read error.
Have you checked the truck for codes when this happens?

 

When / if it happens again I will be sure to look for that light. There is no MIL light that comes on. I only have a generic code reader so I’m not sure if it will read OEM codes.

It totally makes sense that it could be the immobilizer module or possibly the chipped key is worn or faulty.

I remember now several years ago where I worked at the time. I had a Chevy pickup that was doing the same thing. In 30 minutes the module would reset and then it starts. The security light on this truck was flashing and I think it would stay lit for a while ever after the reset.

Thanks for spiking my memory. I’ll be sure to observe the next time it occurs. My girlfriend was driving it the other day when it happened. I’ll be sure to tell her to look for the light if it happens again

thanks so much for your reply… you got me steered in the right direction anyway