Toyota Tacoma starting issue

I posted in January about my (Tacoma 2009 2.7L) that was having cranking issues. I took it to a mechanic and they replaced the crank sensor. Obviously it didnt fix it because I still have the problem. I replaced the slave cylinder because it was leaking. Still have problem. I replaced the clutch safety switch, still have problem. This truck still will have random instances where it will crank, drive, then wont crank again. But it will crank when roll it off and pop the clutch. When I drive it, it purrs like a kitten. No bogging or hesitating and no smell of any kind. It just has random times that it will not turn over no matter what I do. Pop the clutch seem to work 90 % of the time. I am now afraid to drive it somewhere for fear it will not start. I dint know where to look next. No Codes or anything are showing in diagnostics. Im mad at this truck right now! Sad Face

 

I'm asuming you mean it does not crank (as in engine does not turn at all) or anything when you turn the key or the engine turns but doesn't fire?

Will it start if you hit the Clutch Start Cancel switch?

 

Do you hear a single small click when it doesn't crank then nothing?

It could be the starter solenoid contacts need replacement.

 

I don't suppose the ignition cylinder is going bad?

 

It's a strange issue.
https://www.tacomaworld.com/threads/toyota-tacoma-starting-issue.822662/

It cranks, but doesn't start.
It will start if you press the clutch cancel button, BUT....only if the clutch is NOT pressed in.
Or you roll the truck off and "pop the clutch".

It's an odd issues that we'd need to be there to "see" and test ourselves. (or at least I would).
That is why I didn't help back in her first post. I can't give any "helpful" advice.

FWIW, they crank sensor has been changed. The problem still persist.

 

I say , contact Ivan , he is a well known youtuber , Penn- Collège grad, works on cars and trucks like yours with strange issues. I don't know how much he charges, but I see one of his videos say ; he won't charge any vehicles he can not fix. here is his YouTube channel: Pine Hollow Auto Diagnostics -
https://www.youtube.com/@PineHollowAutoDiagnostics/featured
Good luck.

 

Ah, the only thing I could think of and I can't say that I've ever seen it is the thrust bearing on the crankshaft being worn enough to allow the crank to move far enough forward when thw clutch is depressed that the tone wheel is out of alignment of the crank sensor.

Of course the only way to prove this is with an oscilloscope on the crank signal wire.
I suppose you could check crankshaft end play and see if it's in spec as well.

Ivan for sure could figure it out, he is a diagnostic genius and unlike most shops he guarantees his diagnosis and repairs but he isn't cheap.
http://www.pinehollowdiagnostics.com/

 

It seems to be somewhat temperature related too.
Cold engine, it usually starts fine.
Warm engine, warm outside temps.....not so much.

OP you can correct me if I'm wrong.
I'm going off what you posted in the other thread.

 

I dont know... Havent tested that yet

 

No...it just turns and doesnt fire. If I roll it offdown a slope and pop the clutch it will start

 

No. No clicks

 

I don't really have any DIY tests for this one, I'd really want to put a scope on the cam and crank sensors to see if I'm getting the correct patterns when it doesn't start.

 

Ok, thanks for your info. Could it be a fuel pressure problem?

 

By the symptoms I don't think so but without testing we can't really rule anything out.

With what your describing I'd really want to scope the cam and crank signals and check crankshaft end play.

 

Ok. That will be my next step. I will keep you posted. I appreciate your input