help car wont start!!!! need help!!!
Is the tune also compensating for the 3 bar map? You've changed alot of stuff. Is the FPR boost referenced? If so and you set it at 35 psi with the engine off (pump on), as soon as it get's any vacuum, it will pull the fuel pressure down. I would keep cranking the pressure up as high as 80 psi just to see if it helps. Also, check the crank sensor as that tells the PCM which injector to squirt as stated above. Leave the charge pipe off for now until you get it started. check the cam sensor as that is also involved in the initial start. By check them I mean, make sure they are plugged in good and that you dont have a frayed wire or bad contact. Check the grounds on the back of the head also.
Is the tune also compensating for the 3 bar map? You've changed alot of stuff. Is the FPR boost referenced? If so and you set it at 35 psi with the engine off (pump on), as soon as it get's any vacuum, it will pull the fuel pressure down. I would keep cranking the pressure up as high as 80 psi just to see if it helps. Also, check the crank sensor as that tells the PCM which injector to squirt as stated above. Leave the charge pipe off for now until you get it started. check the cam sensor as that is also involved in the initial start. By check them I mean, make sure they are plugged in good and that you dont have a frayed wire or bad contact. Check the grounds on the back of the head also.
yes the tune is tuned for a 3 bar the fpr is boost referenced ive tried it as high as 60 as i was told by nick to leave it at 30 but i can try 80 i guess
they are both pluged in im pretty positive. dumb question but theyre both located on the back of the engine correct?
as of right now this is what happend i tried to start it and it back fired i looked under the car and the waste gate was smoking and there was a puddle of fuel about the size of a quarter under. i duno but i thought maybe id try to start it with the waste gate open so i took the vaccum lne of the fpr and and had my buddy hold the air hose to it at 15 psi enough to open the waste gate i tried to start it and it back fire through the intake and had a flame i duno!!! it has fuel andspark and air i know that atleast. o yeah i had the charge pipe off of it so it was open tb
please help thanks guys!!!
do what? theyre sided? i had my coil packs off and had the harnesses laying together i thought they were the same on both sides do you mean the harness that runs to each coil or the main big wiring harness?
Ever tried to start a carbed small block when the dist is 180 out? Don't look in the carb when rolling the motor over, I learned the hard way. Took about a month to grow my eyebrows back.
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8 sec potential, 12 sec slip
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From: Savannah, GA
the crank position sensor is on the oil pan. you will need to take the starter off to get to it. I almost guaruntee you have something up with it. make sure all the wires going to it are not broken or ripped.
What could make it 180 degrees off? Can the crank sensor do that? Ill check all the wires but I don't think they're messed up. If they were would it do as I described?
Thanks guys yall really are helping more than you know
Thanks guys yall really are helping more than you know
The only other thing would be that the fueling is not happening correctly. You said that there was fuel under the wastegate which would mean raw fuel in the exhaust. That should be a noticeable smell. If this is indeed the case, I would try going back to the old inj without the driver box and the old tune.
I'm the guy who got the harness from speed inc with the 2 wires switched around. I went through all the same steps you are gong through. My 3 bar adapter harness had the 2 outside wires switched around. I spent a few days trying to get my car running and couldnt so I took a break and looked over everything again and noticed that the adapter harness used the same colors as the stock MAP harness and the 2 outside colors were switched around so I decided to pull the pins out, reposition them and give it a try just because I had ran out of ideas and it worked. May not be the issue here but thats my 2 cents.
my 2 cents
I have 96# injectors and versafueler...fp at like 35....not a prob.
the harness from speed inc can be flipped over and plugged in the other way. the way that LOOKS right is wrong......been there done that but it should at least fire.
If you have any way to scan, see if you have a rpm signal while you are trying to start it. No rpm signal means cam or crank sensor or wiring. I really think you have a ground not hooked up. 3 grounds on back of drivers head...one on each shock tower and a few underneath radiator area
If you have a scanner you can see what the map kpa reading is with just the key turned on. It should be like 90-100 kpa and go down while starting the car.
Sounds like the injectors are not firing.... versafuelr connected to wrong wires is my guess
the pink wire on every injector plug is the power from fusebox...the (color) wire with black stripe on each plug is the trigger wire from the pcm....thats the wire the versafueler gets spliced into
Be sure the main power wire for the versafueler gets power WHILE cranking and not JUST once the car is running...several power wires are like that
Be SURE you have spark. connect a plug to one wire and turn over the motor and you should see spark. I dont believe the plug even has to be grounded. i think you do have spark or the plug would be wet.
I have 96# injectors and versafueler...fp at like 35....not a prob.
the harness from speed inc can be flipped over and plugged in the other way. the way that LOOKS right is wrong......been there done that but it should at least fire.
If you have any way to scan, see if you have a rpm signal while you are trying to start it. No rpm signal means cam or crank sensor or wiring. I really think you have a ground not hooked up. 3 grounds on back of drivers head...one on each shock tower and a few underneath radiator area
If you have a scanner you can see what the map kpa reading is with just the key turned on. It should be like 90-100 kpa and go down while starting the car.
Sounds like the injectors are not firing.... versafuelr connected to wrong wires is my guess
the pink wire on every injector plug is the power from fusebox...the (color) wire with black stripe on each plug is the trigger wire from the pcm....thats the wire the versafueler gets spliced into
Be sure the main power wire for the versafueler gets power WHILE cranking and not JUST once the car is running...several power wires are like that
Be SURE you have spark. connect a plug to one wire and turn over the motor and you should see spark. I dont believe the plug even has to be grounded. i think you do have spark or the plug would be wet.
Last edited by cablebandit; Jul 31, 2009 at 09:41 PM.
My guess is it has to do with the map sensor, tune or a combination of the two. My car wouldn't start with a 2 bar map and 1 bar tune. So if you have a 3 bar map and it is actually a 2 or 1 bar tune, then it won't start. You could think you have the right map sensor and actually don't or you could have the same trouble that HUMMER had. It's really a simple fix if it is this, you just have to find out what it is.
Just out of curiosity, could you post how you have your regulator lines routed. If that's wrong that could hinder a start also.
Just out of curiosity, could you post how you have your regulator lines routed. If that's wrong that could hinder a start also.
ok i bought a new crank posotion sensor and checked all the wires for it and wrapped them all seperatly in black electrical tape and still nothing!!! back firing out the intake i know its a 3 bar map and that it was tuned for 3 bar that was a very specific part of the convo. with nick
i duno im so frustrated!!
i duno im so frustrated!!
I'm the guy who got the harness from speed inc with the 2 wires switched around. I went through all the same steps you are gong through. My 3 bar adapter harness had the 2 outside wires switched around. I spent a few days trying to get my car running and couldnt so I took a break and looked over everything again and noticed that the adapter harness used the same colors as the stock MAP harness and the 2 outside colors were switched around so I decided to pull the pins out, reposition them and give it a try just because I had ran out of ideas and it worked. May not be the issue here but thats my 2 cents.
https://ls1tech.com/forums/pcm-diagn...ts-down-3.html
can some one sum this up for me its kind of confusing do i have to have a scanner to do this?
http://gearchatter.com/viewtopic8876...c4c95b000c7121
http://gearchatter.com/viewtopic8876...c4c95b000c7121
It would be cool if we could see the tune too. I know I had issues similar to yours when I first plugged my 57# lowZ injectors in. I scaled them right but it was HP Tuners that has the IFR table flow listed wrong. I have pointed this out to them and they still havent fixed it. If you hover your mouse over the IFR table without opening it and you read the bottom of the screen that describes the table it says that the table is in g/sec but its not, the table is actually lb/hr. It would pop and backfire, I also had to change my oil because it was just dumping gas, my car thought it had 8# injectors due to the g/sec values lol.
so did you have a bad map sensor or a bad harness?
https://ls1tech.com/forums/pcm-diagn...ts-down-3.html
https://ls1tech.com/forums/pcm-diagn...ts-down-3.html
It would be cool if we could see the tune too. I know I had issues similar to yours when I first plugged my 57# lowZ injectors in. I scaled them right but it was HP Tuners that has the IFR table flow listed wrong. I have pointed this out to them and they still havent fixed it. If you hover your mouse over the IFR table without opening it and you read the bottom of the screen that describes the table it says that the table is in g/sec but its not, the table is actually lb/hr. It would pop and backfire, I also had to change my oil because it was just dumping gas, my car thought it had 8# injectors due to the g/sec values lol.
but it doesnt really sound like the harness tho because your car would actualy start tho correct? it wouldnt make it back fire and stuff if the map sensor harness was bad would it?