Long crank, sputtering low idle, and won't go into gear when cold.

Over the last couple days I've noticed some issues with my Tacoma that weren't apparent on the test-drive or in videos sent to me by the PO. He even sent me a cold start vid where he touched the exhaust manifold and it started right up.

Basically it doesn't seem to like to start after it's been sitting for 5 hours or so. It'll crank for a while and kind of sputter to a start and idle really low at around 400 rpm, like it wants to stall out, even with the clutch in. It also is impossible to get into 1st gear before the engine comes up to temp. Believe me, I've tried. Reverse also gives me trouble but I can usually muscle it into R, but not without some grinding noises. The other gears are very notchy when cold, but especially 1st and to a lesser extent, reverse. I've been having to start in 2nd til it warms up. It does gave a Marlin Crawler short-throw shift kit installed by the PO. Eventually when the truck is up to operating temp it'll start shifting like butter and idle fairly normally, though it can be a little rough and pulsating, from 600 up to 1000 rpm, seemingly without rhyme or reason.

It also feels more sluggish than expected, but I'm hoping that's from all the extra weight I'm hauling around in the back (spare axle, front diff, leaf springs, frame plates, etc.), and not anything with the engine itself. The PO told me the knock sensor codes are on, but I've been unable to confirm as I'm waiting on an OBD2 reader with the correct connection port on it.

Anyway, this all seemed like a bizarre constellation of symptoms, so I'd appreciate any insights on where to start with it, or if anyone's had a similar experience.

Thanks for reading.

 

I don't envy tearing the top off the engine just to do knock sensors and the knock harness, not a fun job

 

The PO seemed to think the codes were trivial and wouldn't effect anything, but yea that was on me to do more research on what replacing them would actually entail. Not sure if the codes are related to the above issues or not.

 

The knock sensor codes put the truck in a sort of limp mode where ignition advance is real low, makes em a good bit weaker.

 

It does feel like a bit of a dog now that you mention it. I had convinced myself it was trivial like the P0401 on my LC but it looks like I've been caught off guard here. Looks like the labor to fix them is crazy. Do you know if it's safe to drive with the codes, other than it being underpowered?

 

Yeah its not a fun job by any stretch, but is doable with basic tools, the sensors are kinda high priced though. Anywho, it should be safe to drive, but it'll be a dog and waste fuel

 

I’m averaging 17 mpg when I calculated it so I thought that seemed normal with the 275/70/17s. Like I said it does feel sluggish though and has a hard time with cold starts and the idle is a bit unpredictable. I found a vid from Timmy the Toolman so at least it’s doable DIY, just looks tedious.

 

As long as that is accounting for how much the speedo is off that does seem pretty okay mileage wise.

 

That was just a tank calculation, but if anything I should be travelling future than the odo displays with the stock 4.10s I’d think.

 

Now I'm thinking I should do a compression test and oil analysis before I do anything just to make sure the engine hasn't been damaged.

 

Both are great insight, I'd do a leakdown if the compression comes back not so great, sometimes those let you know whats up and it can be something cheap.

 

So apparently the code came on after the PO changed the plugs and wires. He said he used to get the long crank but hadn't in a while.

I might try to sell the locked/4.88 axles to finance the knock sensors and harness. The camper too and maybe frame plates too. Also might take off the Tundra calipers and bigger wheels/tires. Just wanna get the truck back to stock. Just have to research what all that would go for.