LQ9 408 no start
08-25-2013, 05:47 PM
#1
On The Tree
Thread Starter
iTrader: (2)
Join Date: Mar 2007
Location: Michigan
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
LQ9 408 no start History: Car is a 1993 TA and was a 6 Speed car and 5 years ago I did an EFI Connection conversion to the LT1.
Current Condition: Built a 6.0 to a 408, 823 heads, LS3 intake, SVO42 lb injectors, Racetronics 255 fuel pump, Crank is a Callies and the cam is a custom grind.
PCM was bench top tuned for my setup.
Engine will crank, have fuel pressure, coils are grounded with power, crank sensor shows 5v and Cam Sensor is reading 10.7 High voltage, .27 Low Voltage with 12V from PCM, PCM has PWR at correct times and shows Ground @ all 4 grounds.
Problem: I have no spark or Fuel coming into the chamber!
Noid light test shows no signal @ injectors at all.
I have replaced sensors, done test after test and the only thing that I can think of is that the PCM is stuck in VATS some how.
Can anyone shed some light on this for me at ALL......I'm stumped and search out........I just need some help.
Thanks
Current Condition: Built a 6.0 to a 408, 823 heads, LS3 intake, SVO42 lb injectors, Racetronics 255 fuel pump, Crank is a Callies and the cam is a custom grind.
PCM was bench top tuned for my setup.
Engine will crank, have fuel pressure, coils are grounded with power, crank sensor shows 5v and Cam Sensor is reading 10.7 High voltage, .27 Low Voltage with 12V from PCM, PCM has PWR at correct times and shows Ground @ all 4 grounds.
Problem: I have no spark or Fuel coming into the chamber!
Noid light test shows no signal @ injectors at all.
I have replaced sensors, done test after test and the only thing that I can think of is that the PCM is stuck in VATS some how.
Can anyone shed some light on this for me at ALL......I'm stumped and search out........I just need some help.
Thanks
Last edited by Phantom383; 08-25-2013 at 08:26 PM.
08-27-2013, 08:20 PM
#3
On The Tree
Thread Starter
iTrader: (2)
Join Date: Mar 2007
Location: Michigan
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
Well I have redone ALL my test and the car STILL isn't firing so I'm going to take the PCM back to my tunner and have him check and reprogram the PCM.
08-29-2013, 08:50 PM
#4
Staging Lane
Join Date: Jun 2013
Location: Socal
Posts: 55
Likes: 0
Received 0 Likes
on
0 Posts
I know from experience that if you do not have a solid engine to chassis ground strap it will not fire, even though everything seems fine and it can even crank without it. I had the exact same issue for about 3 minutes. Luckily with my ECU we can look on the laptop if the crank and cam are active and in sync. If not = no injector pulses or spark.
Next question to ask is; was the PCM setup for 24X or 58X reluctor and was it setup for a cam sprocket with 1 large phase/tooth or 2+ teeth like some later models?
Next question to ask is; was the PCM setup for 24X or 58X reluctor and was it setup for a cam sprocket with 1 large phase/tooth or 2+ teeth like some later models?
08-31-2013, 02:58 PM
#5
On The Tree
Thread Starter
iTrader: (2)
Join Date: Mar 2007
Location: Michigan
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
I know from experience that if you do not have a solid engine to chassis ground strap it will not fire, even though everything seems fine and it can even crank without it. I had the exact same issue for about 3 minutes. Luckily with my ECU we can look on the laptop if the crank and cam are active and in sync. If not = no injector pulses or spark.
Next question to ask is; was the PCM setup for 24X or 58X reluctor and was it setup for a cam sprocket with 1 large phase/tooth or 2+ teeth like some later models?
Next question to ask is; was the PCM setup for 24X or 58X reluctor and was it setup for a cam sprocket with 1 large phase/tooth or 2+ teeth like some later models?
Yes the PCM is set for a 24x and all my sensors are for a 2000 Ta so they are 24x also.
The crank has the 24x wheel, 2pc
I'll check the ground strap again!
Thanks for the response
Last edited by Phantom383; 08-31-2013 at 04:03 PM.
09-01-2013, 06:42 AM
#7
"I have replaced sensors, done test after test and the only thing that I can think of is that the PCM is stuck in VATS some how."
VATS comes into play AFTER the engine starts....
"PCM has PWR at correct times ".. Does this mean you checked for power w/ the key in the crank position??
VATS comes into play AFTER the engine starts....
"PCM has PWR at correct times ".. Does this mean you checked for power w/ the key in the crank position??
Trending Topics
09-01-2013, 02:09 PM
#8
On The Tree
Thread Starter
iTrader: (2)
Join Date: Mar 2007
Location: Michigan
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
"I have replaced sensors, done test after test and the only thing that I can think of is that the PCM is stuck in VATS some how."
VATS comes into play AFTER the engine starts....
"PCM has PWR at correct times ".. Does this mean you checked for power w/ the key in the crank position??
VATS comes into play AFTER the engine starts....
"PCM has PWR at correct times ".. Does this mean you checked for power w/ the key in the crank position??
I had the PCM reprogrammed and I still have the same issue, just like the PCM don't want to release the command to fire
Am I right in this thinking:
Cam sensor has a PWR and Ground but the Crank don't so does the Cam sensor have to ground out to the PCM before the Crank sensor sees the reluctor to tell everything to fire?
Or am I backwards in my thinking?
09-02-2013, 11:29 AM
#9
On The Tree
Thread Starter
iTrader: (2)
Join Date: Mar 2007
Location: Michigan
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
Well issues keep coming up!
I did have the 2 outer pins on the Crank Sensor backwards, swapped them and she backfired........and that was it and now I'm back in the same boat AGAIN!
No spark, no fuel getting into chamber (have it at rail) and she'll crank till the battery is dead.
Then I found that #5 injector quit getting PWR for some reason but all the others work just fine, I grounded each one out to test them.
Soooooo I'm going to rip out the harness sometime before Christmas and rewire the injectors.
I have to get packing cause I sold my house and we have 40 days to get out and the garage is going to be the bastard!
Thanks for everyone's help that posted
I did have the 2 outer pins on the Crank Sensor backwards, swapped them and she backfired........and that was it and now I'm back in the same boat AGAIN!
No spark, no fuel getting into chamber (have it at rail) and she'll crank till the battery is dead.
Then I found that #5 injector quit getting PWR for some reason but all the others work just fine, I grounded each one out to test them.
Soooooo I'm going to rip out the harness sometime before Christmas and rewire the injectors.
I have to get packing cause I sold my house and we have 40 days to get out and the garage is going to be the bastard!
Thanks for everyone's help that posted
