Originally Posted by JMat

I had the same thing happen to me so my vote is crank position sensor and it's easy to diagnose if you have a scanner. Mine didn't throw a code, just wouldn't start one day and I used my Torque app to verify the issue. If when your cranking the engine and your scanner doesn't show any RPM it's the CPS. It should register somewhere around 200 rpm.

Originally Posted by BamaDrewski

There are lots of threads about 3rd gen T4R’s and Tacomas with 5VZFE engines that “crank but won’t start” and I had that issue develop on mine this past Friday on my way to work.

I did the usual stuff – cleaned the IAC, throttle body, MAF, checked the plugs, wiring, vacuum tubes, etc.

Was thinking it is the fuel pump (original pump at 325K miles and ordered all the stuff to change out the pump.) Doing research today however, I ran across something called the COR (Circuit Open Relay) and I am going to change that out first. (You must take the driver’s side panel off from under the steering wheel and it is located under the left-hand side of the relay/circuit box)

Stayed tuned and will let everyone know if it works!

Anyone ever heard of this and tried it? If so, did it work?