SCcobaltSS's Engine Build
Well i mentioned the balance shafts cuz they got marks on there for links. First thin i would do would be to take the timing cover back off and retime everything, if you didn't do that already? the way we timed my old one was have the crank at 5 with the pink link, and red and blue up top. you should also turn the motor manually to see if it's building compression while you turn the cams with a wreck or the crank.
Also how long has the car been sitting and not been moved or started?
Also how long has the car been sitting and not been moved or started?
Well my injector scaling should be correct. I did the tune the way I normally would have and checked it with the spread sheet posted by a couple people on a different site. The only thing that was different was the short pulse and short pulse adder were off a little.
MAF may be off but I have not change the size of the tube. Yes more air is "possibly" allowed due to the LS4 TB but the MAF should calculate that and should no be off significantly to where it wont fuel in the relm of ignition, so I think.
I am willing to try anything. I do have my 60's still, I can put them in. I dont have my TB and I cant find one in phoenix at a junk yard. Hope someone is in phx that I can borrow atleast.
Again this is not me knocking down your comments I am just trying to make a rebuttal. If you see it being wrong let me know. I am always up for more learning!
MAF may be off but I have not change the size of the tube. Yes more air is "possibly" allowed due to the LS4 TB but the MAF should calculate that and should no be off significantly to where it wont fuel in the relm of ignition, so I think.
I am willing to try anything. I do have my 60's still, I can put them in. I dont have my TB and I cant find one in phoenix at a junk yard. Hope someone is in phx that I can borrow atleast.
Again this is not me knocking down your comments I am just trying to make a rebuttal. If you see it being wrong let me know. I am always up for more learning!
I hope you get it running! I love seeing all these new lsj builds lately!!! Cobalts are really starting to put down good times and BIG numbers.
Well i mentioned the balance shafts cuz they got marks on there for links. First thin i would do would be to take the timing cover back off and retime everything, if you didn't do that already? the way we timed my old one was have the crank at 5 with the pink link, and red and blue up top. you should also turn the motor manually to see if it's building compression while you turn the cams with a wreck or the crank.
Also how long has the car been sitting and not been moved or started?
Also how long has the car been sitting and not been moved or started?
#1 125
#2 125
#3 130
#4 130
On my other post I had them backwards. So these are the numbers
I am just rebuttaling what is being said with what I have done up to now with the car.
Well i was just popping up some ideas that I could thin of while sitting here. Pull your injectors out of the head and crank the motor seeing if your injectors are squirting enough.
Pulled the injectors. They were shooting fuel to the sky! lol all four!
I stepped on the gas pedal and TB went from 22% to 100%.
I stepped on the gas pedal and TB went from 22% to 100%.
Last edited by SCcobaltSS; Apr 23, 2010 at 08:15 PM. Reason: Automerged Doublepost
UPDATE: I lost spark. I got a new crank and cam sensor. I installed the cam sensor and got Cam sensor performance code, so I change the hex on it and it went away. I then checked spark since I knew where the next pitson should fire and nothing. Look at all of the connections and nothing out of the ordinary. So I said **** it and changed the crank sensor. (that was a bitch! There is no room) I am going to try to see if I have spark now.
Well this thing is acting weird. I lost fuel when I lost spark. I dont get it.
Oh and no codes either
Oh and no codes either
Last edited by SCcobaltSS; Apr 24, 2010 at 01:01 AM. Reason: Automerged Doublepost
LSX RWD S/C conversion
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Joined: 03-25-05
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From: Maple Ridge, BC, Canada
Everytime I went to start my engines after they were rebuilt (x3) I always started them up with just the stock tune.
I hope you are not just trying to start your engine with turning it over continously as you run the risk of cylinder wash from too much gas which is really bad for the rings.
Too bad that you don't have a stock throttle body because the main thing is to start & breakin the engine, not performance. I would have used stock or stage 2 injectors as well for your initial start up. Trying to tune for everything before the car even runs, allows for too many variables to isolate individual issues.
I hope you figure out the problem.
I hope you are not just trying to start your engine with turning it over continously as you run the risk of cylinder wash from too much gas which is really bad for the rings.
Too bad that you don't have a stock throttle body because the main thing is to start & breakin the engine, not performance. I would have used stock or stage 2 injectors as well for your initial start up. Trying to tune for everything before the car even runs, allows for too many variables to isolate individual issues.
I hope you figure out the problem.
Senior Member
Joined: 11-12-07
Posts: 1,537
Likes: 0
From: Maryland
vats can defantly do whats going on. thats what i was saying about when i put the wrong pcm in my car, it cranked, but vats was not allowing it to start. i agree with going back to what your positive that works, old TB, old injectors, old tune. one less variable and its pretty easy to change
Everytime I went to start my engines after they were rebuilt (x3) I always started them up with just the stock tune.
HI hope you are not just trying to start your engine with turning it over continously as you run the risk of cylinder wash from too much gas which is really bad for the rings.
Too bad that you don't have a stock throttle body because the main thing is to start & breakin the engine, not performance. I would have used stock or stage 2 injectors as well for your initial start up. Trying to tune for everything before the car even runs, allows for too many variables to isolate individual issues.
I hope you figure out the problem.
HI hope you are not just trying to start your engine with turning it over continously as you run the risk of cylinder wash from too much gas which is really bad for the rings.
Too bad that you don't have a stock throttle body because the main thing is to start & breakin the engine, not performance. I would have used stock or stage 2 injectors as well for your initial start up. Trying to tune for everything before the car even runs, allows for too many variables to isolate individual issues.
I hope you figure out the problem.
vats can defantly do whats going on. thats what i was saying about when i put the wrong pcm in my car, it cranked, but vats was not allowing it to start. i agree with going back to what your positive that works, old TB, old injectors, old tune. one less variable and its pretty easy to change
So I checked all the fuses again. Checked all the connections, no problems. System is seeing RPM and have no codes. Still not started. Still not getting spark and fuel.
Ok so I did some test and found out my car is actually not seeing RPM. I guess I looked at an older log. Now I have to figure out why its not seeing RPM. I have a new cam and crank sensor.
Are you 100% sure you are getting signal from the crank sensor? Is it pulsing when the car is cranking? Is there supply voltage to it?
If yes, then check the same thing at the PCM pins.
If yes there, bad PCM.
If yes, then check the same thing at the PCM pins.
If yes there, bad PCM.
New Member
Joined: 05-19-08
Posts: 118
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From: Lake Zurich, IL
What is the the ecotec use for a sensor for measuring RPM's?
Go from there track back... E.I wires.
The computer wont give any spart or fuel if its reading 0...
And does the engine at lease crank over?
Go from there track back... E.I wires.
The computer wont give any spart or fuel if its reading 0...
And does the engine at lease crank over?
It does crank. Just no spark or fuel now. I am going to look at the pin outs and connectors to the sensor and ECM to hopefully see the problem..