Checking for spark?

[ls1nova71]

Just checked out your build thread to see what kind of pump you're using and I think I found your problem, the truck isn't low enough..... Truck looks killer man! However I didn't find out what you're using for a pump. If you are getting fuel out of the filter, but not at the rail, something is seriously wrong since there should be no restrictions between the two. First and foremost, you should really get a fuel pressure gauge instead of just pushing in the schrader valve on the rail. That said, you should have pressure at the rail after the pump shuts off for quite a while. If the pressure is bleeding off, then you've got a leak somewhere. Could be the regulator like you said, but if it's not leaking fuel when you pull off the vacuum line, I would suspect it's going to be good. To be loosing pressure, you could have a stuck open injector, but you probably would have found that out by now, because it will hydrolock an engine in a pretty short amount of time. If that's not the case, then it could be the pump, if it's an intank pump, make sure the hose between the sender and the pick up tube is still on and the clamps are tight and there are no holes in it. Get a fuel pressure gauge and see what the pressures are actually reading and go from there. Just because you are getting a large amount of fuel out of the filter doesn't mean you have the correct pressure, and "large amount" can be a relative term, if you are not sure what the amount should be, it may just seem like you are getting the right amount when actually you are not. Also what I meant by the pump being wired backwards was the positive and ground wires on the pump reversed. They will still pump fuel running in reverse, but it won't be enough. Make sure the power is on power and ground is on ground.

[BR3W CITY]

Have you hotwired the fuel pump yet so you KNOW you'll have full fuel to the rail? You can't blame the regulator if the fuel never gets to it.

So when the truck goes key-on, it runs for the 2 seconds, and is looking for Rpm's. It won't command the pump to run again, until it sees Rpm. The hotwire bypasses this. If you do this, and it still won't fire, next step is to verify fuel pressure (with a gauge).

As part of this, if the crank sensor is not hooked up, damaged, etc....then that will trick the engine into not "Seeing" those rpm's as I mentioned above. This will cause the fuel pump to not run, and it will also cause spark symptoms.

[smartass12]

So i got a fuel pressure gauge and i get no pressure at all whether two seconds or crank. i do smell a fuel pretty strong in the engine bay, possibly injector/injectors are stuck open being that i have no clue how long this motor was sitting or last started

[smartass12]

I did also try to jump the fuel pump off battery. pump ran fine but still no fuel pressure at the test gauge.

[paul mora]

Not sure if you have a return on the fuel system if you do do did you cross the lines and your pumping into a check valve

[smartass12]

Originally Posted by paul mora

Not sure if you have a return on the fuel system if you do do did you cross the lines and your pumping into a check valve

I will check (hope im a knucklehead and that is all it is).

Next step i guess will be pull line from fuel rail and see if it is pumping gas to the rails.

For piece of mind (im sure a waste of money) i did install a new pressure reg on the rail to eliminate that as a possibility.

Now lets say i am getting fuel to the rail after testing it...what else in the rail could cause it to get zero pressure at the schrader valve?

[ls1nova71]

Yeah, I would pull the feed line and make sure you're getting presure there, if you are, then there should be no reason not to get fuel at the gauge. Unless there's some junk in the rail, like a big bug crawled in there when it was sitting open. I wouldn't think it will be likely though. You could try removing the schrader valve from the rail to make sure its opening, they unscrew just like a tire valve stem an take the same tool. If you are not getting fuel to the rail but are getting fuel out of the filter you have a clogged or kinked line somewhere. They are bad about kinking at the flex part at the rail but you can't see it because of the outter covering on them. What kind of filter are you using?

[smartass12]

Originally Posted by ls1nova71

Yeah, I would pull the feed line and make sure you're getting presure there, if you are, then there should be no reason not to get fuel at the gauge. Unless there's some junk in the rail, like a big bug crawled in there when it was sitting open. I wouldn't think it will be likely though. You could try removing the schrader valve from the rail to make sure its opening, they unscrew just like a tire valve stem an take the same tool. If you are not getting fuel to the rail but are getting fuel out of the filter you have a clogged or kinked line somewhere. They are bad about kinking at the flex part at the rail but you can't see it because of the outter covering on them. What kind of filter are you using?

First want to say thanks for everyones help in trying to figure this out for me cuz im lost.....

I am using this filter http://www.summitracing.com/parts/rus-650130

[smartass12]

Originally Posted by paul mora

Not sure if you have a return on the fuel system if you do do did you cross the lines and your pumping into a check valve

Paul is a genius and i am an idiot!!!!!! the line were backwards....

We HAVE fuel pressure gentlemen!

So i did try to start it for a couple times and nothing.

Beacause it kinda (cough) started with starter fluid im guessing maybe getting new injectors?

[smartass12]

Does it matter that i dont have the MAF hooked up and plugged in while just trying to start it?

[siggyfreud]

Originally Posted by smartass12

Does it matter that i dont have the MAF hooked up and plugged in while just trying to start it?

I have had cars idle without, but poorly. I'd connect it just to take one more potential fault point out of the way.

Are you sure the injectors are firing? Can you hear them clicking on and off, or have a noid light to see if they're getting the signal to fire during crank?

[Custom 68]

great news you got it figured out. I would bet your injectors are plugged up or stuck. They can be cleaned, you can clean them, send them off or you can get new ones.

It will run without the MAF you will get codes of course. The temp should also be in your MAF so it may think it is cold and throw a bunch of fuel in.

Good luck, one step closer.

[BR3W CITY]

If the tune is decent and VE tables are close, it should idle alright, just probably boggy and sloppy on the pedal.

The maf is just a quick molex plug tho, no reason not to have it for startup.

[smartass12]

I dont have a noid light but have an extra spark plug so i wrapped a ground wire tight around the treads of extra plug and had it plugged into the coil and tried to crank and see spark. i only checked three and none had spark. makes sense as to why starter fluid wouldnt fire it up completely. going to check the others this morning in this fashion. Please someone chime in if me checking for spark this was doesnt work, i dont want to be chasing an electrical problem if im wrong in this test..

[ls1nova71]

Noid lights are for checking for injector pulse. If it sputters on starting fluid, I would lean towards clogged injectors, since that is way more common than having more than one coil go bad all at once. Take them out and soak them in some Seafoam overnight and then put them back in and see if it starts. You can also check them with a 9v battery to see if you hear them click, just do it quick, don't hold the power on for very long.

[smartass12]

I agree, i doubt 3 coils to go bad at same time which leads me to believe it has to do with harness. i was meticulous about the pinout from lt1swap.com but i have heard from others the the (current performance) ls fuse box/relays might be wired wrong on their end to make it run. my harness looks like crap anyway and i think i might just call bill (bp-automotive) and just buy something i know will work. its just getting frustrating

[ls1nova71]

Didn't you say it tried to start on the starting fluid? If it tried to start, then I would think the wiring would be alright. If you suspect the fuse box, have you checked for power at the coils and injectors? If you have power on those pink wires, then check all the other pink wires for power and the two orange wires for constant power. If all your powers are good, make sure you have your grounds grounded good. This is most likely going to be something simple you are overlooking. You can basically take all the pink wires and the two orange wires and tie them all together, add power to them and if you have fuel and grounds hooked up, it will start (VATS deleted of course). I have started several on the garage floor this way in less than a half an hour. But before condemning the harness, have someone turn the engine over while you listen and feel the injectors to see if they are working. You can put a large screwdriver on one and put your ear on the handle to act as kind of a cheap stethoscope, and you should head an audible "click", you can also feel it. If you don't get that, then you need a noid light to make sure it's getting a signal, but if you have power to them and your grounds are good, they should work. If there's no signal to them, check your crank sensor behind the starter. Make sure it's plugged in, and if it is, pull the loom off of it and trace it for as long as you can to make sure the wires are not damaged. If you feel a soft spot in the wires it could mean the wire is broken inside the insulation. But before all of this, I would spray a little more starting fluid in it and see what happens. Open the throttle body and spray it in the intake, just don't go crazy, a second should do it (count one Mississippi), then try to start it and report back with what happens.

[ivorton74]

got mine started today..turns out it was because I didn't block off my egr port on the intake manifold

[smartass12]

Originally Posted by ls1nova71

Didn't you say it tried to start on the starting fluid? If it tried to start, then I would think the wiring would be alright. If you suspect the fuse box, have you checked for power at the coils and injectors? If you have power on those pink wires, then check all the other pink wires for power and the two orange wires for constant power. If all your powers are good, make sure you have your grounds grounded good. This is most likely going to be something simple you are overlooking. You can basically take all the pink wires and the two orange wires and tie them all together, add power to them and if you have fuel and grounds hooked up, it will start (VATS deleted of course). I have started several on the garage floor this way in less than a half an hour. But before condemning the harness, have someone turn the engine over while you listen and feel the injectors to see if they are working. You can put a large screwdriver on one and put your ear on the handle to act as kind of a cheap stethoscope, and you should head an audible "click", you can also feel it. If you don't get that, then you need a noid light to make sure it's getting a signal, but if you have power to them and your grounds are good, they should work. If there's no signal to them, check your crank sensor behind the starter. Make sure it's plugged in, and if it is, pull the loom off of it and trace it for as long as you can to make sure the wires are not damaged. If you feel a soft spot in the wires it could mean the wire is broken inside the insulation. But before all of this, I would spray a little more starting fluid in it and see what happens. Open the throttle body and spray it in the intake, just don't go crazy, a second should do it (count one Mississippi), then try to start it and report back with what happens.

Ok, i will start with that before completely hittting the panic button.

Originally Posted by ivorton74

got mine started today..turns out it was because I didn't block off my egr port on the intake manifold

I do have the big port blocked off on the side but not the tiny port on the top yet...think that matters? what did you use to block the one on top?

[ivorton74]

Originally Posted by smartass12

Ok, i will start with that before completely hittting the panic button.



I do have the big port blocked off on the side but not the tiny port on the top yet...think that matters? what did you use to block the one on top?

Probably...if the egr port in the intake manifold is not blocked properly it wont start....i used a 1 3/8' freeze plug and i also got about off kit for the ports on the exhaust manifold.

[Custom 68]

I have been thru a couple of these issues and they were both stuck injectors. It seems to be very common with these.
On my first one I unhooked the coil packs and raised the injectors out of the manifold. I hooked up one at a time and with my son cranking the motor I tapped the injector till it fired then went to the next one. It may not have been the safest... but I am cheap and it worked for me. That was 10 years ago. I think fuel has gotten worse around here with the amount of alcohol in it.
Just recently my buddy had the same issue we tried that and got some to work but we took all his out stuck them in a coffee container and cover them with sea foam. He decided to strap them to his law tractor and mowed that "agitated" them and cleaned them up good. They fired up great and have been running ever since. Poor people have poor ways as the saying goes.
Don't panic just slow down and you will get it. When I did mine there was not nearly as much information out.
Good luck.
Dave

[smartass12]

So i bought new injectors and will try to get them in this weekend (time permitting). At least i will be able to rule out stuck injectors at that point.

[truckdude239]

why would you buy new injectors? the old ones can be soaked in seafoam and unclogged/stucked. i mean i know its quicker but man them things cost an arm and leg

[smartass12]

Originally Posted by truckdude239

why would you buy new injectors? the old ones can be soaked in seafoam and unclogged/stucked. i mean i know its quicker but man them things cost an arm and leg

Cuz im in panic mode! Always empties my pockets lol

[ls1nova71]

Originally Posted by smartass12

Cuz im in panic mode! Always empties my pockets lol

Dude, SLOW DOWN!!! I understand your impatience, but throwing money at a problem is only for people with more cash than sense. Did you try the starting fluid again? I'm guessing no? If you're going to buy stuff, I would have bought a set of noid lights and checked for injector pulse, but that's in the past now. You could still buy a spark tester or just check it the old fashion way by putting a screwdriver in the boot and holding it close to bare metal on the block. I'm not sure the old plug method you used is the best way. If you still get no spark, and your power and grounds are good, it most likely going to be a crank sensor issue, either the sensor or mosf likely the wiring from it. Know anyone with a good scanner or tuning software you can use to see if the PCM is seeing RPM during cranking? Also, are you absolutley sure you're not loosing power while cranking? Some circuits are hot in 'run' but not during 'crank'. To test this, turn the ignition on, and then jump the solenoid at the starter. MAKE SURE THE TRUCK IS IN PARK AND CANT MOVE SHOULD IT START.