2002 Sequoia Stalls when I try starting

I have a 2002 Sequoia. About a week ago, I pulled my boat out of the water with it and set off a wave of issues: will not go into / out of 4wd, ABS light came on, and it now stalls immediately when starting.

The stalling has me the most concerned. It started to have a rough idle when I got the boat home and was backing it into a parking spot. I then have had a hard time starting it. I need to press way down on the gas pedal prior to turning the key or else it will stall after starting. Once it is running it seems to do ok, maybe idles rougher than normal.

I have replaced the fuel filter, spark plugs, air filter, Air flow sensor which sits above the air filter. None of these have helped. Seems it is not getting enough gas when starting up. Wondering if it is the fuel pump? I ordered a fuel pump relay switch to try it as I read it is a possibility.

Other issues from that day which are likely unrelated but who knows. I put it in 4wd to get up the boat ramp, the orange light has been blinking since, seems to be stuck in 4WD. My ABS light also went on.

thanks.

 

Well, it's never the fuel filter.

I see you've thrown a lot of parts at it. Before you went and bought a (hopefully Denso brand) fuel relay, did you bother trying to jumper the pins of the relay to force power to the fuel pump?

Have you tested for fuel pressure while cranking to verify if you're actually getting any fuel?

Timing belt is supposed to be changed every 10yr/100k miles, was it done recently? (Often times the wire for crank position sensor is mis-routed during that process, it gets nicked by the timing belt, and that sensor is required to activate the fuel pump).

Do you have any codes at all?

How many miles.

If it happens to be the fuel pump, as with all electronics on these trucks, stick with Denso brand, and don't buy from scAmazon or fleaBay, lest you'll end up with a counterfeit.

 

Thanks Shifty,

I replaced the timing belt when I bought it 7 years ago at 185k and it has 225k now. Bought it in upstate NY, the frame had been replaced and I was looking for a large SUV to tow boat, 4WD, etc. The spark plugs were done around the same time so most of this was general maint, fuel filter was never change since I bought it, I was always worried about changing it due to the rust. I wish it could have been the fuel pump.

I did not jump the fuel relay, figured I would just try it after after watching some YouTubes. I did buy a Denso but on SCamazon so who knows. We recently moved and I misplaced my code reader so not sure of the codes. When we moved, I lost the mechanic who took care of me for years, and I have not found anyone locally I have liked to this point.

Open to other suggestions....


thank you.

 

Next no-cost step I'd be doing is to confirm the fuel pump. You need fuel delivery, properly timed good spark delivery, and metered airflow for that engine to run. Fuel pump is as good a place as any to start confirming the three.

But before you check the fuel pump, you should check the wiring for chewing. If you have rodents nearby, or you park outdoors regularly, it's not uncommon for them to crawl in the opening under the intake manifold, where the starter & knock sensors live, and chew up the wiring (causing no-crank, knock sensor circuit codes). Likewise, they love nesting on top of the gas tank, and they'll chew up both the wiring like this, killing the pump (crank-but-no-start), and chewing up the tank tubes/plastics like this (EVAP codes, EVAP small leak, EVAP large leak). They'll chew through the gas filler neck, which will also throw EVAP codes, like this. It's common enough we can share exact photos of it, and there are more where those came from.

I'll share a video, but it's important to point out one piece of bad info in the fuel pump one. That is, the fuel pump is not "ON" with the key in the ON position as this person says. It turns on when the engine is cranking. If memory serves, once the engine starts, the ECU relies on input from the crankshaft position sensor as a trigger to open the fuel relay. The fuel relay has two voltage paths it toggles between for powering the fuel pump: Send power DIRECT to the fuel pump so it runs at high pressure, or send it an alternate route thru the fuel resistor, which dumbs down the voltage, making the pump run in low pressure mode.

Why am I telling you that? Well, a relay has a ground and power feed. It has a voltage trigger wire from the ECU. Then it has a couple of legs that, when the trigger feeds it, it sits on one leg, else it switches to the other. You should be able to figure out which is the ground leg and which is the hot leg to force the fuel pump to stay on in high pressure mode. This video is showing how to do it on an '02 Tundra and so you can confirm how the circuit/ECU operate, this PDF may be helpful and this PDF will help with testing the resistor that allows dropping to low-pressure mode (you can simply bypass it to test if you want).

Here's a good video on fuel diagnostics:

https://www.youtube.com/watch?v=VoerlgT8pck​

Another great video on starting diagnostics, maybe not as applicable:

https://www.youtube.com/watch?v=0jWouSQYTnU​

 

Thank you for the links, I appreciate you help Shifty, I will look at these.

I was able to find my scanner yesterday, it is pretty basic, but it gave me code's P0100 (mass or volume air flow A circuit) and P0101 (mass or volume air flow A circuit range).

Maybe the low voltage flow is not working. I need to press the gas pedal 1/2 - 3/4 prior to turning the key to start it, revs to 3000 rpm then idles a bit rough. Possible it could be critters but truck was running fine then idle became rough before I even shut it off.

 

Seems like a wild array of symptoms, and throwing parts at it, especially when you're using aftermarket stuff from the LAPS, or ordering online from sources notorious for knockoff/white box/counterfeit parts, it only makes things potentially worse.

Let me know if I got this right .... In one day your Sequoia saw:

• 4HI (or 4LO?) light began blinking orange (not green) while pulling boat at the launch
• ABS light suddenly appeared
• Truck stalls immediately while starting

You parts-canon'd it with parts from scAmazon:

• Fuel filter
• Spark plugs (big no-no to ever order these on scAmazon/fleaBay, major source of counterfeits)
• Air Filter
• MAF (really should buy Hitachi for this, it's OEM)

Only codes you're finding stored are P0100 and P0100, both related to MAF circuit. I'd be curious if you still saw those after putting the original MAF back in and clearing codes.

[IF ANYTHING ABOVE IS WRONG, LMK]

Things you mentioned toward the end there are pertinent: If you hold the gas pedal halfway down, then crank, it'll turn over and run, albeit roughly. I gotta ask: Have you checked the throttle body for gunk?

I would check the wiring on top of the fuel tank just to be certain (use a mirror, your phone in selfie mode, whetever you gotta do.

I would remove the negative battery cable for 10 minutes to force the ECU to reset/re-learn next time.

I would jumper the fuel relay to bypass it for low voltage mode.

I would watch this video and consider cleaning the throttle body, heeding his warning about the truck potentially running like shit after - I think you'll see why I'm recommending this option when you get to the point where he shows how the linkage works etc:

https://www.youtube.com/watch?v=3B-a8WJtd8w​

 

According to how far out in water you had to go, you may have blown some fuses in particular EFI NO 2. Those 2 codes are indicative of the MAF sensor losing it's +12vdc input. If the rear oxygen sensors were too low in water, it's plausible it blew the EFI NO 2 fuse, which as mentioned feeds the MAF sensor also. The sluggishness may simply mean it went into limp mode.

Might be a swing and a miss but I'd definitely check my underhood fuses.
If any are blown, replace and then unhook battery to reset ECU memory and see if anything is still setting a code.

In case you want to check for +BATT voltage at MAF.....

 

Thanks BubbaW,

I will check the fuses but did not need to go into the water other than the back tires. I did replace the fuel pump relay and it helped. I tried to start it after replacing the FPR and it stalled, tried again an it worked w/out pressing gas. Throughout the last two days, it does not immediately stall but I need to give it some gas. I will try putting back the original MAF.

 

I will try cleaning the throttle bottle, I had cleaned it out a bit when I replaced the air filter but not as comprehensive. Wondering if I should reset it after watching the video. Spark plugs I used were Denso 4504 platinum. Will try to take a look over the gas tank to see how it looks, prefer not to drop the tank but I have let the gas get pretty low just in case.

As far as the 4WD, When I pushed the 4WD button, it did put it in 4WD but now all 4 wheels show green and the middle light is flashing and it is stuck in 4WD. I only put it in 4WD occasionally to exercise it. Thinking about taking the cover off the actuator to see how the connections look before getting in too deep. I am not hearing anything behind the dash when I press button, goes between showing all 4 lit up with light flashing and no wheels lit up with light flashing. I put it in 4 Lo manually but did not change anything. Would be nice if there was a way to shut down the electronic shift from 2WD to 4WD and just shift it manually?

I will get a better scanner to figure out ABS. Last year I had the entire rear end changed with one from Southern CA because mine had a lot of rust and the rear diff was starting to seep fluid, replaced parking brake cable, shocks, rear ABS sensors when it was done. Thinking maybe ABS is from the front because came on when I locked the front differential.

 

On the ABS stuff, you may want to pop out the front ABS sensors, clean them off, reinstall, just to see if any change.

But ultimately a scanner that can connect into the ABS network and see what's set there would be ideal instead of plugging blindly.