2013 dies repeatedly while driving down the road

[indycole]

I've chatted with my father and think I'm going to pick up a variable voltage power supply to see if I get the same behavior if I direct drive the fuel pump. I'm nervous what might happen if I put 12 volts to it for an extended period (recalling the warning from the fsm).

The power supply should be just fine for driving the pump, but I wouldn't drive the fuel pump ECU with it. It sounds like the fuel pump ECU is expecting a square wave. Maybe rent an oscilloscope to get more info about the waveform? Then, if needed, you could potentially drive that with a function generator.

 

[Swampmonger]

If you’ve been measuring a square wave with an RMS multimeter the amplitude of the wave should be about 2xRMS. 12-13Vp is about what’s expected, right?

 

[CharlieS]

The power supply should be just fine for driving the pump, but I wouldn't drive the fuel pump ECU with it. It sounds like the fuel pump ECU is expecting a square wave. Maybe rent an oscilloscope to get more info about the waveform? Then, if needed, you could potentially drive that with a function generator.

Sorry, to clarify, I was going to drive the fuel pump directly, completely bypassing the ECM and FPC ECU.

I am not smart enough to operate an oscilloscope or a square wave generator.

 

[drftsub]

Thank you.

I like the open loop/closed loop theory, but if I am to trust the code reader, that changeover happens quickly. It starts out on open loop (OL) and goes to closed loop (CL) around 10 seconds, and dies before I see another change in this status. Maybe that is just a problem with the reader I use (it only works when the car is running...).

I went to try the idea of disconnecting the O2 sensors and didn't see the connectors handy. Any pointers to where they are? I didn't get underneath yet.

The 02's are just after the exhaust manifolds but before the upstream cats . Unfortunately a little buried.

 

[chilibit]

I thought since O2 sensors are key to the emissions control system that a problem there would trigger
codes you could find with an OBDII reader. Could the open/closed theory be valid even it the sensors
are fine? Perhaps so.

 

[drftsub]

I thought since O2 sensors are key to the emissions control system that a problem there would trigger
codes you could find with an OBDII reader. Could the open/closed theory be valid even it the sensors
are fine? Perhaps so.

It is not uncommon for an 02 sensor to have a "soft" failure where it reads off or "slow". If this occurs it may not trigger a CEL. That said, unplugging them also forces the ECU to stay in open loop to test for correction based issues.

 

[chilibit]

Ah, that makes more sense than my intuition. Tks.

 

[CharlieS]

I just got out from underneath and see the O2 sensors, but no plugs are visible to disconnect. The harness seems to disappear up into the body toward the engine bay. Looking at it from topside, I can't see where they come up. Any guidance for how to disconnect them so I can run this test? Do they have a plug in the engine bay?

 

[indycole]

C56 and C20. Both dark grey.

 

[CharlieS]

I had asked: "The SFI System > ECM Power Source Circuit tech doc shows a box for the "integration relay", inside which it shows IG2 and EFI relays; and an IG2 fuse and a EFI fuse. The first inspection procedure is to inspect the integration no. 1 relay (step a. Remove integration relay from engine room relay block. Where is this - I don't see it labeled as such?"

It is in the engine bay fuse and relay box, passenger side rear of the box. It has four fuses in it A/F, Horn, EFI MAIN and IG2 MAIN. And it has a C marked on it. It is also clearly labeled in the fusebox diagram (ERJB.pdf) posted by indycole yesterday, but I didn't see it somehow. It has two small tabs on the narrow ends that hold it in, and there are three connectors underneath. Presumably there are integral relays inside (but it is a black box).

I just spent an hour or so taking readings on this and the wiring between it and the ECM. I got some readings that were strange, and some that didn't make sense to me, but I'm not sure how to type it up unless people are familiar with the troubleshooting steps.

Some highlights:

• In the EFI and IG2 relay tests (pg 2 of 7) on the Toyota techDoc
  • 1C-1 - 1B-4
    • Battery voltage not applied to 1B-2 and 1B3 read OL (offline) no resistance (should read 10 kohms or higher)
    • Battery voltage applied to 1B-2 and 1B3 read OL (offline) no resistance (should read below 1 ohm)
  • 1C-1 - 1B-8
    • Battery voltage not applied to 1B-7 and 1B-6 read OL (offline) no resistance (should read 10 kohms or higher)
    • Battery voltage applied to 1B-7 and 1B-6 read OL (offline) no resistance (should read below 1 ohm)

So is the integration relay bad, or was something flawed with my testing? I followed the manual to the tee, but I shouldn't have had four bad tests. That being said, I did a lot of other testing and it came out good.

Some odd ones:

• Check harness and connector pg 4/7 of Toyota Techdoc
  • 1B-8 or A38-28 (IGSW) to body ground - both read 167.5-ish ohms. The spec is 10 k ohms or higher. This seems a LOT higher. Is that OK , or something to pay attention to?
• All kinds of weirdness
  • A38-1 - 1B-4 No resistance
  • A38-34 - body ground read OL . but . 1B2 - body ground 5 M ohms
  • A38-2 or 1B4 - body ground Both were 159.00 ohms (spec is 10 k ohms or higher)
  • A38-1 - body ground read OL

I don't know how to interpret this...

Based on this testing, I am suspicious of the integration relay and may try to locate one to test out.

 

[CharlieS]

C56 and C20. Both dark grey.

View attachment 2069289

Thanks, that looks doable.

Update: doable if you have skinny arms... I managed to unplug the driver's side. I couldn't find any way to remove the passenger side. Not a lot of room to maneuver in there, at least with arms the size of mine. With one unplugged I started the car, hoping that it would be enough to throw the car into whatever mode you described. I got the flashing trac and low range lights (same as when I disconnected the MAF and the time I unplugged the ECT sensor). Regrettably, the vehicle still stalled after a minute and fifteen seconds.

 

[indycole]

Is the procedure you're following the one in "ECM Power"? I will say that if you've followed those procedures and get bad readings from the relay test then that's definitely a red flag. The "weirdness" would make sense if you happened to miss a line about whether you're testing while components are plugged into their natural home vs. bench-tested.

I also attached a general ECM output check doc.

 

[DWSD]

I am new to this thread. It is interesting.

1. in the GM world and some applications, they use PWM (pulse width modulation) to regulate fuel pressure via duty cycle of the fuel pump. I don't know if the control module is in the pump, in the main ECM or a separate ECM, but use of PWM for fuel pump pressure is normal with newer (performance) engines.
I assume Toyota has the same.

2. I'd think the fuel pump control module, if the source of the problem, would have its own diagnostics to report an issue if it is failing. I I realize a guess here doesn't help you.

Do you have a way to measure fuel pressure?

This thread validates a few things... but not definitive answer.

Engine quits on start up

Thought I could pick your brains for a minute. I've got an '07 5.7 TRD SR5. On two seperate occasions I have had the following happen: Turn the key, engine turns over and engine catches and revs. (chill of satisfaction runs down spine!) However, after a second, the engine quits. Turning...

www.tundrasolutions.com

 

[CharlieS]

I am new to this thread. It is interesting.

1. in the GM world and some applications, they use PWM (pulse width modulation) to regulate fuel pressure via duty cycle of the fuel pump. I don't know if the control module is in the pump, in the main ECM or a separate ECM, but use of PWM for fuel pump pressure is normal with newer (performance) engines.
I assume Toyota has the same.

2. I'd think the fuel pump control module, if the source of the problem, would have its own diagnostics to report an issue if it is failing. I I realize a guess here doesn't help you.

Do you have a way to measure fuel pressure?

This thread validates a few things... but not definitive answer.

Engine quits on start up

Thought I could pick your brains for a minute. I've got an '07 5.7 TRD SR5. On two seperate occasions I have had the following happen: Turn the key, engine turns over and engine catches and revs. (chill of satisfaction runs down spine!) However, after a second, the engine quits. Turning...

www.tundrasolutions.com

Thanks. I haven't gotten around to getting a setup to test fuel pressure on this car, but I probably should.

 

[grinchy]

Can’t you use a 9v battery to temporarily drive the fuel pump? Or a parallel of several 9v if it requires more amps?

 

[CharlieS]

I'm not sure if a 9v battery or batteries would work. I have a voltage supply coming on Friday, and would rather wait.

A friend had something similar happen with her Tundra, and shared some info that sounds interesting. Her truck shut down as well, and after repeated visits to the dealer, they found an issue with the electronic throttle control system.

Does anyone have experience troubleshooting the electronic throttle control system? My understanding is that this system has two pairs of sensors (VTA/VTA2, VPA/VPA2), two in the pedal assembly and two in the throttle body, and if they are in conflict, the ECM will shut the engine off.

I have to imagine that I can monitor those four sensors real time in Techstream. Does anyone have access to the ranges I should expect, or data about the relationship/correlation between the four sensors?

If so, I expect that I should be able to prove/disprove this line of thinking pretty quickly.


Edit - FSM has this info.

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

The APP sensor is mounted on the accelerator pedal bracket and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type and uses Hall-effect elements in order to yield accurate signals even in extreme driving conditions, such as at high speeds as well as very low speeds. The voltage, which is applied to terminals VPA and VPA2 of the ECM, varies between 0.5 V and 4.5 V in proportion to the operating angle of the accelerator pedal (throttle valve). A signal from VPA indicates the actual accelerator pedal opening angle (throttle valve opening angle) and is used for engine control. A signal from VPA2 conveys the status of the VPA circuit and is used to check the APP sensor itself.

The ECM monitors the actual accelerator pedal opening angle (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.

I can test the pedal in Techstream:
Throttle sensor voltage % - VTA - range 0-100 - 10-22% pedal released - 64-96% pedal fully depressed
Throttle sensor 2 voltage %- VTA2 - range 0-100 - 42-62% pedal released - 92-100% pedal fully depressed

And there are a series of dozen wire harness resistance tests and a troubleshooting sequence that I can use to see if the accelerator pedal is functioning correctly.

If I read it right, there is a failure mode without DTCs and CELs.

 

[supdizzle]

does anyone on here have access to an All Data type system? Being able to search within a tech type forum for similar issues with the fixes would be very useful here.

 

[CharlieS]

does anyone on here have access to an All Data type system? Being able to search within a tech type forum for similar issues with the fixes would be very useful here.

I subscribe to alldatadiy.com for some of our other cars. It is $19.96/yr or $34.95 for 5 yrs.

I hadn't even thought of using it for the cruiser. Good idea. I'm not familiar with the search forum part of it, only the factory service manual, service bulletin and wiring diagram piece.

I just added the cruiser for $14.95 /yr (they give a discount on subsequent vehicles after the first). Note if you are looking for the Land Cruiser, it is in the Toyota Truck section.

 

[CharlieS]

I think I need to step back and start over. I haven't been systematic in my troubleshooting, and I've gotten sidetracked. This isn't a good way to diagnose a complex problem.

Here's my fresh plan: I'm going to clear the DTCs, and then run the car to observe the behavior and get the DTCs again (with Techstream connected so I have some freeze frame data). From there, I am going to systematically troubleshoot the P1603 code using the diagnostic flow from the FSM. In case someone in the future needs this, it can be found in doc number RM0000021140DAX found in the General section of the 2013 FSM (pp.592-632).

This may not happen until the weekend, since I think it will take several hours to step through each part and be thorough.

I'm not trying to shut this thread down at all. I'm still very open to ideas and suggestions. This has all been very helpful and generated a lot of good data. I've already learned a lot.

I just think I need a fresh plan of attack. In the absence of stumbling into it, I don't think I will get to a root cause unless I am rigorous about how I do the troubleshooting.

 

[NLScooby]

FWIW - I have a 95 Porsche and my DME relay went out on me the other day with very similar symptoms. I was on the highway and the car lost power, shut off and the lights on the dash went on. I would pull over and the car would restart and then die after a few seconds.... Apparently, once the contacts (solder joints) in the relay cracked internally, the heat (and expansion) would cause the contacts to stop...um....contacting. When the car shut down, it would cool just enough to contract and reestablish contact until it heated up again and lost it.

My point is that the relay's you checked (like my DME relay) would checkout as operational when cool, but not when up to temperature..... Could you subject the relay(s) to heat while testing them?