stuck in limp mode

2 hours from home when it’s not in limp mode- going to be a fun trip…

Like a dumbshit, I used my spare key to start (try) my 15 Tacoma after fishing. Obviously no luck, and started checking fuses, disconnecting battery, etc. trying to figure it out. Multiple attempts before having my aha moment. She fired right up, but now trac and cel light are on and it’s in limp mode.

aside from a 2k rpm drive home to an obd sensor any ideas?

 

Air pump failure?

 

It’s likely- the pump isn’t making any noise now upon shut down. I’m guessing something in the multiple cranks flooded it and it failed?

 

Have you disconnected the battery again since you got it started?

I've also found after something like that I need to reset and then let it sit in ACC for a minute or so before trying to start

 

I’m sitting with the battery disconnected for a bit right now.

 

This would have been my suggestion too.

Where exactly are you? Maybe someone could bring their obd tool to help.

 

Battery disconnect didn’t work, I’m in Usk, WA and getting on the road heading for Spokane.

 

Get a scanner hooked up and see what codes you get and clear them out and see if they come back.
bluetooth obd2 dongles are pretty cheap and you can load up the Torq app on your phone to read codes, HF has some good cheap scanners too.

 

Try waving the help me flag here.

https://www.tacomaworld.com/forums/north-west.40/

 

You need a scan tool.
Some codes set instantly
Others are 2 trip logic.

Depending on the code, a battery disconnect can be short lived.

 

Made it back home- it is the P0416 secondary air valve stuck. I have tried clearing the code, comes back on. Tried clearing then disconnect, comes back on. I think I’m f’d with an expensive fix.

appreciate the help- changing thread title as HELP is not the issue any more. Thanks for the replies.

 

If you don’t have emission in your state, you can bypass the SAIS.

@hewitt-tech makes a great product.
https://hewitt-tech.com/

Just remember, your truck is for off road use only once you bypass it

 

Send a DM and happy to help troubleshoot

@TnShooter We appreciate you recommending the HT SAIS Bypass Kit. Wanted to provide some additional resources for anyone comes across this thread in the future.

What Does the Secondary Air Injection System Do?
https://www.tacomaworld.com/threads/what-does-the-secondary-air-injection-system-do.780847/

What Do My Secondary Air Injection Error Codes Mean?
https://www.tacomaworld.com/threads/what-do-my-secondary-air-injection-error-codes-mean.780848/

How to Fix Secondary Air Injection System?
https://www.tacomaworld.com/threads/how-do-you-fix-the-secondary-air-injection-system.780849/

 

I appreciate the offer, have checked out your product and very impressed. I am now way past just the SAIS system- turns out I have MAF, O2 (both), heater sensors, and SAIS driver open circuit faults. Grounds have been confirmed on all systems as complete, meaning I get to replace my ECU. 5-6 day wait for the ECU and $.

 

Somehow I doubt the PCM is the problem, they rarely fail.
Have you checked the EFI No 2 fuse?

 

All fuses have been checked. She’s at the dealer right now with a tech I have great history with, spent the entire day testing all fault circuits and fuses.

I agree, first thought was no way something else is wrong, but I spent 15-20 minutes intermittently cranking on it with a spare non chipped key. With the four different fault circuits, and especially since the O2 and heater circuits are both banks, it makes sense the faults are centralized.

I hope so ironically: once you input a VIN for an oem ECU, it’s yours.

 

I should add the resetting codes kills the engine, then they come right back.

 

I hope they are actually diagnosing it and not just throwing parts, I see it so often stuff ends up at our shop that has been multiple places and had everything replaced. Many times it ends up being a simple wiring problem that could have been diagnosed easily with the right knowledge and equipment.

That's pretty normal with a bad MAF signal, when the MAF isn't reading the PCM set's a code, goes into limp mode and ignores it. Clearing the codes while running causes the PCM to start using the faulty MAF signal again resulting in a stall.

 

I recently had this issue, run a 12v to ur blue/white wire on ur maf harness and see if it goes away it just fixed mine and i had the same codes

 

Yea yours was missing power to the sensors, I'm guessing you never tracked down where the connection was being lost?