car turn on...then turns right off....why??
 

on a COLD start my car will turn right on then it will turn right off. any ideas why?


if i take a vacum line off, the car won't turn off, it will stay on.

when the car is warm, the car is just fine. i can turn it off and turn it on and it won't turn off. i'm noticing this on cold starts.

i changed the temp sensor on the head already, made sure all my grounds were getting good connection also.

any ideas?

Re: car turn on...then turns right off....why?? (93hb)
 

Could be anything from the ignition switch, to a couple of sensors to a bunch of things. Need more info

1. How is it warm?

2. On cold starts, can it hold an idle if you give it gas?

3. On cold starts, if you give it gas, will it still die?

fs

Re: car turn on...then turns right off....why?? (93hb)
 

when its warm...it does fine

yeah..it will hold idle if i hold the gas pedal down a little

it will die if i let off the gas. when the car starts to warm up and then i let off the gas, it won't die, but it will idle pretty low. then when its completely warmed up, it does just fine.

any ideas?

Re: car turn on...then turns right off....why?? (93hb)
 

Hey man i had a similar problem. Check your idle air control valve. Had the same cold start problem. and had it cleaned by a friend and no problems since.

Re: car turn on...then turns right off....why?? (SINFULLSPEED)
 

If it does it only on cold starts, then it may be caused by:

a vacuum leak. listen for hisses and such.
The EGR valve may be defective.
The fuel injectors may be dirty.
Bad ECU
Bad coil.

look at crankshaft position sensor for oily deposits and such. Sometimes, this can cause this.

Most probably though it is your idle air control valve
Are you tripping CEL code 14? if so then look at IAC wiring and connections.

if not, start the engine, let it rev at 3000 rpm until the rad fan starts.
then disconnect the connector from the IAC. If the rpm goes down, look at wiring and loose connections and such

if not then you need to install a new one. Then measure voltage between black/yellow and ground. No battery voltage means bad wiring, battery voltage means good wiring.

fs

Re: car turn on...then turns right off....why?? (filthy_shovel)
 

it was none of the stuff ya'll mentioned. it turned out the be the throttle cable.
i have a skunk2 manifold so i need to adjust the throttle cable now so it will work right. the throttle cable was too tight and would close the tb up some.

Re: car turn on...then turns right off....why?? (93hb)
 

hey, when you let go of the ignition, does it die right then?

Re: car turn on...then turns right off....why?? (shivic)
 

sometimes it would. then i would adjust the throttle cable and it wouldn't die anymore.

its the throttle cable. we got the throttle cable adjust good, car idled at 900 rpm and you couldn't tell the car was on, but then the throttle cable would get stuck when i would rev the motor.

i think i fixed it today before i came to work. i don't really want to drive it cause i need to fix my oil return line.