Thread: Starting issue

Wow no other suggestions is everyone just as stumped as I am?

crank position sensor all wired in good?, if the ecu does not see the crank moving it will cut power to the pump within a short amount of time. so u might be able to turn the key over and initially get pressure because the pump will prime for 5 or so seconds, but the ecu will not maintain power to the pump because the crank isnt moving. just a guess?

I always thought it got the signal from the distributor

the ecu recieves signal from both the crank pos sensor (ckps) and cam pos sensor (cps) the signals from each have slightly different function.

from my understanding the cps monitors engine position and speed, and is used to control fuel and spark timing primarily , amongst other things.

i cant remember where i read that the ckps is used as a failsafe so if the engine stops spinning it cuts fuel if u were to get in an accident or something. i know that the cps determines injector firing but i could swear i read the the ckps will cut fuel if the motor stops spinning.

but i think i might be on to something seeing how you lost tach as well?

its gotta be somthing from the harness gause this problem was with the previous motor and now its carried on and gotten worse with this setup

B13's don't have crank shaft sensors on cam angle sensors only b14 up and if it was falty it will still run but throw a code and crank over alot before it runs . I would swap the relay with another one in the vehicle with the same part # like a/c ect ect ...
Also your sure your loosing power to the pump or is it dying and not pumping ? Have you check power at the pump when this problem happens ?

Edit: ok so you posted about tach signal loss . Have you checked the conection at the ecu I've heard and seen a poor connection issues like this but it's a dumb question . Also have you check injector pulse during this issue . Might even be ignition switch related but don't hold me to that Or possible ecu issues . Do you have a spare ecu to test with only reason I say that is because of the loss of tach signal .

Sounds to me like a bad distributor

yes i swapped ecus same issue the injectors have pulse...im gonna see about a new ignition switch

so after days of going crazy and trying not to cut my wrists i finally found the problem. whoever installed the msd ignition box pulled all the wires they need off of wires from the engine harness but at the same token the connector inside the car behind the radio and heat controlls, they unpluged it and ziptied it up so once i plugged it to the other connector on the harness all issues were solved.