Truck starts but won’t drive. No codes. SOLVED

You can unplug the upstream O2 sensor before the cat and see if it will run to check if your cat is plugged before removing the cats from the exhaust altogether.

 

unscrew 02 in front of cat, not in cat....
Pro tip...
Definitely spray 02 now with whatever you got...
if it wont crack loose by turning it counterclockwise wise....
stop before rounding the base...
Try tightening it, you will feel a crack & it will move...
From there, it will come right out...

 

sometimes thats not enough, if theyre really plugged bad...
but easy enough to start there...

Im not going to pretend to know the configuration of this system...

 

You can hook a vacuum gauge up to one of the intake vacuum hoses and see whether the system is losing vacuum as it should when pushing the accelerator down to WOT or if it is stuck in place from an exhaust restriction. You can rent one for free from parts stores.

And you can use a temp gun to see which cat is blocked with a significant temperature gradient in front and behind it.

 

Just finished this. Didn’t work. This thing wants to start it fires up strong but just immediately dies

 

You can have someone put their hand in front of the exhaust pipe while you’re cranking it or even put a shop vac on the tail pipe and open the throttle body and listen to see if it’s pulling any air through.

Shouldn’t be too much work to pop the cat off of the collector pipe if that’s what it comes to.

 

My 2nd Gen may or may not have not thrown a code with a plugged cat and then with a hollowed out cat making all of the ecm emissions checks work out.

 

Just tried to start it and it won’t fire up. It’s turns over but won’t fire up. Is this still consistent with a bad cat?

I’m gonna try fully disconnecting the pipe from the cat and see what that does.

 

Usually they will at least start unless 100% plugged.

You need to make sure you have fuel, pressure, spark, and air.

 

I've seen similar with either the crank sensor and or the open circuit relay going bad.

Starts off randomly, and then gets worst.......ending in crank no start in a few months.

When you test the fuel flow it looks good at crank......and then tappers off....dies

When that relay fails it can leak dia-electric down on its plug below it....like honey


the pig tail on the crank sensor is what fails there......oil, heat, time takes a toll
check that wire and maybe clean its connector....
specific resistivity is why you have to use the oem part here.


Yeah I had new denso crank sensor I'd bought several years ago....
I put off doing it cause pia to pull off the alt bracket..
but that was it......threw in another open relay when I noticed the honey shit

 

I am inclined to throw my hat into the crank sensor or open circuit relay ring as well.

 

Be nice to maybe try another ecm.

 

I’m seeing options for 1 terminal and 2 terminal sensors. How do I know which one I need?

 

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I now drive around with a spare used open relay, and an ignition switch in glove box

that or you should have AAA.......or buddies with pickups and tow straps....



even if crank sensor does not work out.......a spare wont kill you

 

Just replaced the crank sensor. No luck. I’ll keep the old one as a spare. Or put it back in and keep the new as a spare.

I’m gonna let the shop handle this now. Tow truck is on its way now. I just don’t have the time or really even the motivation to go down this rabbit hole again. I’ll update this thread with what the shop says. Thanks everyone.

 

There's a linkage underneath the shifter connecting to the transmission. If I remember right it's adjustable?
And wearable.
Make sure it's actually shifting or in the correct gear.
A bad cat or 02 will throw codes and turn check engine light on.

 

Might not have seen it, but my '08 2nd gen didn't throw a code for a plugged cat to the point where I couldn't get past 1000 rprm and continued to not throw a code when the cats were completely cored out and put in again (part was backordered from Toyota for an increasing amount of time and I was expecting it to be in each month for 2-3 months so yolo'd it back in empty) - all original ECM and AFR / O2 sensors. Only time it'll throw a code is if I go through a big puddle or am at much higher eleveations / cold weather. Not saying this is his case since he seemed to rule out the cats, but just interesting how ECM's won't initiate a fault for a plugged / missing cat every time - OP isn't too far from where I am with similar temp and elevation so there was some chance it could have still been a plugged exhaust.

 

I've only owned 1st and 3rd gens.
Wouldn't know if your 2nd gen situation is relevant, here.

Drove my 1st gen for 15yrs. Had cat and O2 issues up over 200k.
Truck would drive until warm then check engine light would come on. Sometimes it wouldn't start back up until cooled down.
Pulling the EFI fuse to reset the ecu got me by for quite awhile but the codes and engine light kept coming back.
In relation to a different post, I wouldn't clean an 02 sensor with anything other than gasoline.

The shift linkage, I posted about eventually wears out from all the back and forth. If the truck isn't truly in P or stuck somewhere in between gears, the truck may not start.
Could also explain why it starts only sometimes or didn't hardly move when it was started.

Throwing other ideas out there.

 

Just picked it up from the shop. Turns out the ecu had a bunch of water in it from the rain the night before. Drives fine now. Mystery solved.

Now I need to fix where the damn water is leaking from.

 

That's a relief.