help me out...car not starting...
04-26-2007, 12:50 PM
#1
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
help me out...car not starting... Swapped shortblocks out of a buddies car. Swapped cam and heads along with it. Lined cam dots up just fine etc...anyways motor is back in car, has fuel, cranks over and rockers springs all move up and down just fine, seems like something is telling it not to start up...any ideas?
04-26-2007, 01:40 PM
#2
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
-there are 2 grounds on the back of the driver side head, those are both connected,
-I took a fan relay out and swapped it with the ignition relay, still does the same...
-Its definately getting fuel to the rail
-I plugged in a predator to the obdII port so im pretty sure the ECM is fine.
-It just cranks, like i said, springs rockers all move just fine as you are cranking it, so timing chain isnt busted already..
any takers?
-I took a fan relay out and swapped it with the ignition relay, still does the same...
-Its definately getting fuel to the rail
-I plugged in a predator to the obdII port so im pretty sure the ECM is fine.
-It just cranks, like i said, springs rockers all move just fine as you are cranking it, so timing chain isnt busted already..
any takers?
04-26-2007, 02:06 PM
#4
12 Second Club
iTrader: (49)
Join Date: May 2006
Location: College Station, Texas
Posts: 966
Likes: 0
Received 0 Likes
on
0 Posts
Crank position sensor, or cam position sensor. We did a motor swap on a buddies car and had the same results. Ended up being the crank position sensor. It tells the pcm where the crank is in relation to the cam and which coils to fire at which time. He replaced it without me there so I'm not really sure where its at...(btw its easy to break when dropping the motor back on from what I understand...
04-26-2007, 03:09 PM
#5
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
^^^^ just put another crank sensor from a working car, still the same thing...
correct me if im wrong, if the cam sensor is bad, the car would still run? the car isnt even trying to fire...
correct me if im wrong, if the cam sensor is bad, the car would still run? the car isnt even trying to fire...
Last edited by TRU-2GM; 04-26-2007 at 03:16 PM.
04-26-2007, 03:39 PM
#6
12 Second Club
iTrader: (49)
Join Date: May 2006
Location: College Station, Texas
Posts: 966
Likes: 0
Received 0 Likes
on
0 Posts
Fuel or igntion man. Check your coil harnesses and the voltage output of each individual coil. Check all fuses under hood and dash. Also, get a fuel gauge on the shrader valve under the hood off of the fuel rail and be sure you have atleast 50psi fuel pressure when the key is turned forward.
Trending Topics
04-26-2007, 04:42 PM
#8
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by chuckyt1
There should be three grounds on the ds head, two on one bolt and one on the other.
--and there is another ground on the block by the starter going to the battery i think
--and one grounded to the driver side block (small one) and it goes to the frame rail in front of the wheel
--is there anything grounded to the alternator? there is a skinny bolt on the back side of it that isnt doing anything...
04-26-2007, 08:53 PM
#9
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
nevermind, there are definately 3 ground wires on the back of the head. And they are all grounded to the same place on the back of the head...
--coil packs have 12.5 volts to them when the key is turned to on, once cranking they are around 10.5 or so...
--coil packs have 12.5 volts to them when the key is turned to on, once cranking they are around 10.5 or so...
04-27-2007, 01:59 AM
#11
Launching!
Thread Starter
iTrader: (6)
Join Date: Oct 2004
Location: so. missouri
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
did a leakdown test....100% leakdown, NO compression on any of the cylinders. Well 3,5,7 anyway. supposedly this shortblock was swapped out by GM due to piston slap...when really it looks like they may have started to re-ring it and maybe just put them back in without the lower rings before swapping to another crate...sucky deal....
