major issue not starting - crank relearn ? expert needed

**devic** · 07-17-2012, 12:03 AM

the car will crank up sorta to a really rough idle then bog and die, some times it seems like it cranks pretty well running smooth but quickly drops back to a rough idle then bogs and dies

this is the results of coil pack testing

all injector are firing, fuel rail psi @ 40 (thinking the cause of this is the in tank regulator)

some research i have done is leading to possibly needing a crank relearn "if some one with knowledge about this could chime in would be awesome"

also the car sat for 3 years

here a list of parts i have replaced
*newly replaced:
intake gaskets
torque converter
starter
throttle body
throttle body sensors
egr & air delete
fuel filter
racetronix fuel pump 255lph (i have the hot wire kit but have not put it in yet)
oil & transmission fluid
transmission filter
pcv oil catch can
new battery
this is all the new stuff.....

*old mods....
slp lid
02 sims
cat gut
msd wires i made
3" magnaflow cat back
all free mods

**devic** · 07-20-2012, 01:31 AM

nobody has any ideas ?

***SMWS6TA*** · 07-20-2012, 07:15 AM

have you check the crank sensor yet?

**0rion** · 07-20-2012, 09:08 AM

has the crank sensor been replaced or something? What leads you to believe it's a crank sensor issue...the misfires? Seems to me you've already stated your problem....no fuel. At 40psi I'm surprised it's running at all really.

**Knight** · 07-20-2012, 10:16 AM

I'm with Orion. Fix the fuel pressure issue first, then move on. You should see around 58 psi at the rails, with the key in the on position, car not running.

**Knight** · 07-20-2012, 10:17 AM

I also see you list O2 sims. Are those just for the rear O2's, or the front?

**0rion** · 07-20-2012, 11:27 AM

put a pressure gauge on it and see where the pressure spikes too and then where it holds with the key on engine not running. You may have a split hose in the tank although that will usually keep the car from running at all. I just don't see how the car is even starting on 40 pounds. Not sure what the minimum is to open the poppets on the injectors but I would think more than 40.

**devic** · 07-20-2012, 12:09 PM

i ordered the intank regulator already should be here today or tomorrow

**devic** · 07-20-2012, 12:22 PM

im pretty sure the car only need 58-62 psi to operate the return system properly while maintain fuel to the injectors, but ill be replacing the regulator in the tank soon so that issue will be fix at least hopefully, i guess ima go pull the intake off and see if all 3 grounds behind the head are bolted on and look around the engine bay for all the grounds and see what up

**devic** · 07-23-2012, 07:33 PM

any know how the computer operates the drivers to tell which coils to fire and when ?

**2002ssslp** · 07-24-2012, 05:28 AM

Spark, fuel and timing. Thats about all you need to get it running.

**devic** · 07-27-2012, 06:44 AM

thank you for your useless information

**smokestack** · 07-27-2012, 07:04 AM

Originally Posted by devic

any know how the computer operates the drivers to tell which coils to fire and when ?

Crank sensor i think.......
Fairly sure it does anyhow.

**Smittro** · 07-28-2012, 05:57 PM

The teeth in the crank reluctor tell the PCM the crankshafts possition.

Any damage to the crank sensor or reluctor could cause all sorts issues.

Has the pigtail for the sensor or the sensor been damaged? May want to check voltage @ the sensor.

**ls1camino** · 07-31-2012, 03:17 AM

Originally Posted by smokestack

Crank sensor i think.......
Fairly sure it does anyhow.

Cam Sensor = starting
Crank Sensor = running

Personally, if replacing the regulator in the tank doesn't fix your starting issue, then I'd replace the crank sensor. If that doesn't work, put the old sensor back in and move on to the next point of failure...relays.